C USITT DMX512 DMX2000 Rfce1 11
User Manual: USITT DMX512 - DMX2000-rfce1-11
Open the PDF directly: View PDF 
.
Page Count: 79
| Download | |
| Open PDF In Browser | View PDF |
Entertainment Services and Technology Association
United States Institute for Theatre Technology, Inc.
'5$)7
BSR E1.11, Entertainment Technology USITT DMX512
Asynchronous Serial Digital Data Transmission Standard
for
Controlling Lighting Equipment and Accessories
Revision 1.1a
© 1999 Entertainment Services and Technology Association
© 1999 United States Institute for Theatre Technology, Inc.
This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not be published in part or in whole or be duplicated for-profit or sold in any manner.
Reminder -- as noted above, ESTA 'Work in Progress' documents are copyrighted and only may be copied for
the purpose of developing the Standard within the Task Group or Working Group the project is assigned to. It is
the policy of the ESTA Technical Standards Program that publishing of such preliminary information, such as in
this document, in any form, including on Web Pages, is not allowed.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
Inside Cover
The United States Institute for Theatre Technology, Inc. (USITT) is the Association of Design, Production,
and Technology Professionals in the Performing Arts and Entertainment Industry. Founded in 1960, the
mission of the Institute is to advance the professions of design and technology in the performing arts by
disseminating information, actively promoting the advancement of knowledge and skills and facilitating
national and international communication among its members. USITT is the United States Center of OISTAT,
the International Organization of Scenographers, Theatre Architects and Technicians.
USITT
6443 Ridings Rd.
Syracuse, NY 13206-1111
(800) 93USITT
(315) 463-6463
(315) 463-6525 FAX
http://www.usitt.org
The Entertainment Services and Technology Association (ESTA) is a non-profit trade association
representing the North American entertainment technology industry. Its members include dealers,
manufacturers, manufacturer representatives, service and production companies, scenic houses, designers
and consultants. The Association addresses areas of common concern such as technical standards,
customer service, equipment quality, business practices, insurance, and credit reporting, and provides a wide
variety of services to Members.
ESTA’s Technical Standards Committee (TSC) is accredited by the American National Standards Institute
(ANSI) as Accredited Standards Committee E1, Safety and Compatibility of Entertainment Technical
Equipment and Practices with ESTA as its Secretariat. This accreditation means that the ESTA Technical
Standards Program for standards-making has passed a detailed scrutiny by ANSI to insure that it meets the
most stringent requirements for fairness and proper public review of proposed ESTA standards. The
accreditation allows ESTA to submit standards for the ANSI public review and comment process, and then
publish them as ANSI standards. The ESTA Technical Standards Program is now the only ANSI-accredited
standards-making program dedicated to the needs of entertainment technology.
ESTA
875 6th Ave - Suite 2302
New York, NY 10001
(212) 244-1505
(212) 244-1502 FAX
http://www.esta.org
© 1999 Entertainment Services and Technology Association
© 1999 United States Institute for Theatre Technology, Inc.
This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not be published in part or in whole or be duplicated for-profit or sold in any manner.
DMX512-2000rev1.1a.wpd
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi
1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.4 Appropriate uses of this Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.5 Classes of data appropriate for transmission over links designed to this Standard . . . . . . . . . . .
1.6 Classes of data appropriate for transmission using Non-NULL START Codes . . . . . . . . . . . . . .
1.7 Classes of data not allowed on this Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.8 Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.9 Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.10 Cross Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
1
1
3
3
3
4
4
4
4
4
2 Electrical Specifications and Physical Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Electrical isolation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3 EMC compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.4 Topology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.5 Data link common and grounding topologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.6 Preferred method of earth grounding data link common . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.7 Data termination procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.8 Port designations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.8.1 Pin reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.8.2 TYPE classifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.9 Talkback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.10 Device interconnection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.12 Galvanic isolation from protective ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5
5
5
5
5
5
6
6
6
6
7
8
8
8
3 Nominal Operating Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.2 Transmitter characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.3 Earth grounding of data link common for transmitters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4 Receiver characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.5 Earth grounding of data link common for receivers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.6 Earth grounding of data link common for other devices (signal processors) . . . . . . . . . . . . . . . 16
3.7 Loading designation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4 Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2 Minimum Electro Static Discharge (ESD) protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3 Minimum protection against interconnection damage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.4 DMX512 Transmitter protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.5 Earth continuity for ground referenced transmitters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.6 Data link common earth continuity test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.7 Receiver protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.8 Connection integrity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.9 Connection integrity - products with accessory power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
19
19
19
19
20
20
20
21
21
22
–i–
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
5 Data Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.1 Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2 Frame format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3 Packet format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4 Break signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5 Mark After Break . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.7 START Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.8 Maximum number of slots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.9 Minimum number of slots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.10 Defined line state between frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.11 Defined line state between data packets (Mark Before Break) . . . . . . . . . . . . . . . . . . . . . . . . .
5.12 Minimum Break spacing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.13 Dimmer class data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.14 Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
23
23
23
23
23
23
23
24
24
24
24
24
24
25
6 Alternate START Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1 Other Optional START Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.2 Alternate START Code format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.5 Handling of Alternate START Code packets by in-line devices . . . . . . . . . . . . . . . . . . . . . . . . . .
6.6 ASC test packet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.7 ASC text packet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
26
26
26
27
27
27
7 System Information Packet (SIP) Alternate START Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.1 System Information Packet (SIP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.2 SIP format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.3 Control bit field . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.4 Checksums . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.5 SIP Sequence number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.6 Originating universe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.7 DMX512 processing level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.8 Software version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.9 Packet lengths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.10 Number of packets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.11 Manufacturer ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.12 Packet history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.13 SIP Checksum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.14 Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
28
28
28
28
29
29
29
29
29
29
29
30
30
30
30
8 Receiver Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.1 Loss of data tolerance / Resumption of acceptance of data . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.2 Receiver performance at maximum update rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.3 Inactive receiver input circuitry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.4 Packet processing latency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
31
31
31
31
31
9 DMX512 Systems Requiring DC Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
9.1 Accessory Power (24 VDC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
9.2 Limited current 12 VDC power for remote devices (TYPE 5 equipment) . . . . . . . . . . . . . . . . . . 32
– ii –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
10 Connection Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.1 Equipment fitted with external user accessible pluggable data link connections . . . . . . . . . . .
10.2 Equipment intended for fixed installation with internal connections to the data link . . . . . . . . .
10.3 Passive Data Outlets or Wall plate panels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.4 Products providing or requiring 24 VDC Accessory Power . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10.5 Internal connections and specialized products for use with Category 5 cable schemes . . . . .
10.6 Special provisions for TYPE 5 equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
33
33
33
34
34
34
34
11 Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11.2 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11.3 General Applications and between all Portable Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11.4 Cable between permanently installed fixed equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11.5 Specific Requirements relating to the use of Category 5 cable . . . . . . . . . . . . . . . . . . . . . . . . .
35
35
35
35
35
36
12 Marking and Disclosures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12.1 Identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12.2 TYPE and Pin marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12.3 Ground / Isolation marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12.4 Data line termination marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12.5 Required disclosures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
39
39
39
40
40
40
ANNEX A (Normative) - Alternate START Codes Registration & Reserved Codes . . . . . . . . . . . . . . . . 45
A1 Alternate START Code Registration Policy: 1 - 255 decimal (01 - FF hexadecimal). . . . . . . . . . . . . . . . 45
A2 Alternate START Codes Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A2.1 Authorized use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A2.2 Future revisions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A2.3 Test, Text, and System information packets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A2.4 Alternate START Codes reserved for development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
45
45
45
45
45
A3 Requests For Registration of New START Codes and Manufacturer IDs . . . . . . . . . . . . . . . . . . . . . . . . 45
A4 Number of Alternate START Codes per entity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
A5 Selection of the Alternate START Code value and Manufacturer ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
A6 Documentation Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
A6.1 Documentation for use of Alternate START Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
A6.2 Maintenance and Publication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
A7 Supplemental documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
A8 Ownership . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
– iii –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
Annex B (Normative) - Type 3 DMX512 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Annex B Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
B1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B1.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B1.2 Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B1.3 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
47
47
48
48
B2 TYPE 3 Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B2.1 Synchronizing the return data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B2.2 Response frame format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B2.3 Monitor implementation issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
48
48
49
49
B3 Hardware Implementation Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B3.2 Line Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B3.3 UART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B3.4 Line Termination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B3.5 Bi-directional distribution amplifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
50
50
50
50
50
51
B4 Basic Dimmer Status Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
B5 Example return data format detail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B5.1 Headend Firmware Version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B5.2 Headend Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B5.3 Dimmer Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B5.4 Dimmer Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B5.5 Dimmer Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B5.6 Dimmer Detail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B5.7 Dimmer Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B5.8 Dimmer Load Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B5.9 Dimmer Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B5.10 Dimmer Line Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
53
53
54
55
56
57
58
58
59
59
59
Annex C (Normative) - Device Interconnection Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Annex D (Normative) - Port Marking Style Sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Annex E (Normative) - Protocol Implementation Compliance Statement (PICS) . . . . . . . . . . . . . . . . . . 65
– iv –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
Tables:
2.8.2.1 - TYPE classifications for DMX512 equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.8.2.2 - Signal designations summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.2 - Transmitter characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4 - Receiver characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.4 - Transmitter protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.7 - Receiver protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
5.2 - Frame Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
10.4 - Accessory Power Signal designations summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
11.5 - Connection Schedule for DMX512 systems using Category 5 Cable . . . . . . . . . . . . . . . . . . . 36
11.6 - Cable application rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
12.2 - Signal designations abbreviations allowed for marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
12.3 - Ground / Isolation marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
12.5.3 - 5 pin XLR data outlet / wall plate marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
C - Interconnection cross-check (electrical / functional) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Figures:
3.3.1 - Ground Referenced Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.2 - Galvanically Isolated Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.1.1 - Non-Isolated Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.1.2 - Non-Isolated Receiver (other signal outputs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.2 - Isolated Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.3 - Receiver Topology NOT Allowed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.6.1 - DMX512 Processing Device, Floating (Allowed) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.6.2 - DMX512 Processing Device, Grounded (Allowed) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
) .........
3.6.3 - DMX512 Processing Device, Grounded (Only Allowed when Marked
3.6.4.1 - DMX512 Processing Device, Non-Floating (Not Allowed) . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.6.4.2 - DMX512 Processing Device, Grounded (Not Allowed) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.14 - Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.1 - TYPE 5 Dual Sex Power Diode Isolation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11.5.4.1 - Scheme C5.2 with (1) Universe in a TYPE 1 - 5 Implementation . . . . . . . . . . . . . . . . . . . . . .
11.5.4.2 - Scheme C5.1 with (2) universes & (2) TYPE 0 Implementations . . . . . . . . . . . . . . . . . . . . . .
11.5.5 - Mixed UTP & STP / FTP Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B2.1 - Synchronization of Return Data to Control Stream . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B3.4 - External Line Termination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B3.5.1 - Bi-directional TYPE 3 DMX512 Distribution Amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B3.5.2 - Cascaded bidirectional distribution amplifiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11
11
13
14
15
15
16
17
17
18
18
25
32
37
37
38
48
50
51
52
–v–
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
Foreword
The original version of the DMX512 Standard was developed in 1986 by the Engineering Commission of the
United States Institute for Theatre Technology, Inc. (USITT). Minor revisions were made in 1990. DMX512
has gained international acceptance throughout the entertainment industry, even though USITT is not
formally accredited as a standards making body. The earlier versions of this Standard covered only data
used by dimmers. In practice this Standard has been used by a wide variety of devices; this version
recognizes this fact.
In 1998, it became evident that additional updates to the Standard were necessary and formal recognition
through an internationally recognized standards organization was required. The USITT DMX512
Subcommittee issued a Call for Comments in order to solicit recommendations for changes to the Standard.
At the same time, USITT transferred maintenance of DMX512 to the Entertainment Services and Technology
Association (ESTA), which is the secretariat for the ANSI Accredited Standards Committee E1, Safety and
Compatibility of Entertainment Technical Equipment and Practices (more commonly known as the ESTA
Technical Standards Program - TSP).
A Task Group established under the ESTA TSP’s Control Protocols Working Group acted on the proposals
received in response to the Call for Comments. The primary goal was to make editorial updates to DMX512
appropriate for current times, including the addition of technical features while maintaining a balance with
backward compatibility. Many proposals, while technically innovative, could not be accepted because their
implementation would not have been backward compatible and would have immediately rendered obsolete
most of the installed base of equipment.
This document is a result of the actions taken on those proposals and subsequent development under the
Policies and Procedures of the ESTA Technical Standards Program.
– vi –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
1 General
2
1.1 Scope
3
4
5
6
7
This Standard describes a method of digital data transmission between controllers and lighting equipment
and accessories, including dimmers. It covers electrical characteristics, data format, data protocol, connector
type, and recommended cable types.
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
1.2.1 Accessory Power: A 24 VDC supply used to power the electronics and control/drive functions of a
product which does not then require connection to mains voltages. Frequently known as scroller
power but not in fact restricted to use with scrollers.
1.2.2 Asynchronous: Signals that start at any time and are not locked or synchronized to the receiving
device by a separate clock line.
1.2.3 Balanced Line: a data communications line where two wires are present, the signal and its opposite
(complement), the actual signal being the difference between the voltages on the two wires.
Balanced lines have excellent noise and interference rejection properties.
1.2.4 Baud Rate: the rate in bits per second at which serial information is sent.
1.2.5 Bit: smallest unit of data processing information. A bit assumes the value of either 1 or 0.
1.2.6 Break: a high to low transition (space) followed by a low of at least 88 microseconds.
1.2.7 Byte: a data unit of 8 bits.
1.2.8 Common: see Data Link and Signal Common.
1.2.9 Common-Mode Voltage: a voltage appearing equally on the data + (plus) and data - (minus) lines
relative to signal common. Vcm = (Va + Vb)/2 where:
Vcm is the Common Mode Voltage
Va is the voltage on DMX512 Pin 2 with respect to Pin 1
Vb is the voltage on DMX512 Pin 3 with respect to Pin 1
1.2.10 Controller: a transmitting device that originates DMX512 data.
1.2.11 Data +: true signal.
1.2.12 Data -: complimentary signal.
1.2.10 Data Link: physical connection between transmitting and receiving devices.
1.2.11 Data Link Common: The connection to signal common at the point of interconnection (DMX512 Port)
of the product.
1.2.12 Dimmer: a Receiving Device which controls the intensity of light.
1.2.13 DMX512 Port: see Port.
1.2.14 DMX512 Processing Device: A piece of equipment that regenerates the timing of any DMX512
packet or has provision for other signal inputs from which the outgoing DMX512 packet is generated.
In the absence of any DMX512 transmitting capability, the device has provision for other signal
outputs which are controlled in some manner by the incoming DMX512 packet. Basic buffer products
are not normally considered processing devices.
1.2.14 Driver: the circuit which drives the transmit signal and is directly connected to the DMX512 line. See
Line Driver.
1.2.15 Earth Ground: a conducting connection, whether intentional or accidental, between an electrical
circuit or equipment and the Earth, or to some conducting body that serves in place of the Earth.
1.2.16 EMC: Electromagnetic Compatibility. Electrical and electronic equipment may have a requirement to
meet various regulatory standards for EMC. Usually specified in terms of emission and immunity
performance standards.
1.2.17 EMI: Electromagnetic Immunity; see EMC.
1.2.18 Frame: a Start Bit, followed by a Byte and 2- Stop Bits.
1.2 Definitions
–1–
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
1.2.19 Galvanic Isolation: circuit topology in which the output is completely electrically disconnected from
the input.
1.2.20 Idle: the time that the DMX512 line is idle (high) and not sending any information (also known as the
‘Mark’ condition).
1.2.21 In-Line Device: any component that receives and re-transmits DMX512.
1.2.22 Isolation: see Galvanic Isolation.
1.2.23 Isolation voltage: voltage specification between input and output stages of a galvanically isolated
system at or below which damage or breakdown of circuit components will not occur.
1.2.24 Legacy Equipment: DMX512 transmitting and receiving devices claiming compliance with DMX512
or DMX512/1990.
1.2.25 LEN: (Load Equivalent Number) the number or fractions of Unit Loads as defined by EIA-485.
1.2.26 Line Driver: electrical circuit providing differential voltage excursions on a data link, operating within a
defined Common Mode voltage range and with a specified response to overload and overvoltage
conditions.
1.2.27 Line Receiver: electrical circuit allowing detection of differential voltage excursions on a data link,
operating within a defined Common Mode voltage range and with a specified response to overload
and overvoltage conditions.
1.2.28 Loop-Through Connection: A connector or terminal port which connects the signals present on at
least Pins 1, 2 and 3 of one port to another port. Frequently abbreviated to Loop or Thru.
1.2.29 NULL START Code: START Code with a value of 00h.
1.2.30 Manufacturer ID: 2 byte value assigned to a Manufacturer/Organization by the E1 Accredited
Standards Committee for use with Alternate START Codes 91h and CFh. This ID serves as an
identifier that the data following in that packet is proprietary to that entity and should be ignored by all
others.
1.2.31 Mark: a line condition where Signal True is high with respect to Signal Complement.
1.2.32 MAB (MaB): Mark After Break – the period of time between the low to high transition which signifies
the end of Break and the high to low transition which is the start bit of the START Code.
1.2.33 MBB (MbB): Mark Before Break – the period of time between the end of the last stop bit of the last
Slot and the high to low transition which signifies the start of Break.
1.2.34 Merge Unit: Product comprising one or more receiving devices and one or more transmitting devices
that generate a DMX512 packet derived from the manufacturers declared logical combination of the
DMX512 input packets.
1.2.35 Packet: Reset Sequence followed by all slots up to a Mark Before Break and the start of next Reset
Sequence.
1.2.36 Port: a DMX512 signal connection point (connector or terminal strip).
1.2.37 Reset: see Break.
1.2.38 Reset Sequence: a sequence of a Break, Mark After Break, and properly framed START Code.
1.2.39 Receiver: see Line Receiver.
1.2.40 Receiving Device: a piece of equipment which accepts a DMX512 signal.
1.2.41 Signal Common: the common reference (zero volt supply) of the EIA-485 driver or receiver circuitry.
1.2.42 Slot: a sequentially numbered data Frame in a DMX512 packet. A single Universe contains a
maximum of 512 Slots, starting at Frame 1. Frame 0 is the START Code.
1.2.43 Slot Footprint: The number of consecutive slots of data used by a product in its operation.
FPN: A 24 way dimmer rack may have a footprint of 24, it may be more if some slots are used to
provide additional control functions using NULL START Code packets. Automated fixtures are
renowned for having many and various slot footprints.
1.2.44 Space: a line condition where Signal True is low with respect to Signal Complement.
1.2.45 Start Bit: the extra bit attached to the beginning of a byte to indicate to the receiver that a new byte is
being sent. The start bit is always low, i.e., Space.
1.2.46 START Code: the first byte send after Break, indicating the type of information to follow.
–2–
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
2
3
4
5
6
7
8
9
10
1.2.47 Stop Bit: the extra bit(s) attached to a byte to indicate the end of the byte – DMX512 has 2 stop bits.
The stop bit is always high, i.e., Mark.
1.2.48 Terminator: device or circuit topology which is designed to minimize unwanted signal reflections on a
data link.
1.2.49 Transmitting Device: a piece of equipment which produces a DMX512 signal.
1.2.50 Universe: a DMX512 data link originating from a single DMX512 source. Control of up to 512
DMX512 slots comprises a single universe.
1.2.51 Update (Refresh) Rate: the number of DMX512 packets sent per second.
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
This Standard is intended as a guide for:
27
28
29
30
31
32
33
34
35
36
37
38
39
Equipment designers and general users of this Standard must recognize that this Standard is intended to fill
only a limited range of uses. Other standards will be more appropriate for different uses. This is not intended
to be a venue wide network that can carry data for lighting, sound, and scenery mechanization, for example,
all on the same wire. The basic protocol is made up packets that are blocks of un-typed data. Receivers
must know what to do with the data simply by knowing the data's position in the block.
40
41
42
43
DMX512 is designed to carry repetitive control data from a single controller to one or more receivers. The
control data should be used to control dimmers, other lighting control devices and related non hazardous
effects equipment.
1.3 Applicability
1. Equipment manufacturers and system specifiers who wish to integrate systems of lighting equipment and
accessories, including dimmers, with controllers made by different manufacturers.
2. Equipment manufacturers seeking to adopt a standard controller-lighting equipment digital transmission
protocol.
3. System specifiers and consultants to gain detailed information about recommended cable types and
allowed connectors.
4. End users to identify possible problems with the interconnection and communication of DMX512
equipment.
Use of this Standard is strictly voluntary. Furthermore, it is not intended as a replacement for existing
protocols already manufactured, but rather as an addition to existing protocols which will broaden the
installed base of controllers and lighting equipment that can communicate with each other.
1.4 Appropriate uses of this Standard
This Standard performs no error checking of NULL START Code packets. There is no assurance that all
DMX512 packets will be delivered. It is common practice for merge units and protocol convertors to drop
packets that they cannot process in a timely manner. The 1986 and 1990 versions of the Standard
specifically allow dimmers to ignore packets that they cannot process in a timely manner, and this concept
survives in this version of the Standard with respect to NULL START Code packets.
1.5 Classes of data appropriate for transmission over links designed to this Standard
–3–
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
1.6 Classes of data appropriate for transmission using Non-NULL START Codes
2
3
4
5
6
7
It is recommended that most data be sent in NULL START Code packets since they are universally
supported. Nevertheless, where configuration data, data requiring a structured format, or data requiring
checksum or other error checks are sent, the use of registered Non-NULL (Alternate) START Codes is
appropriate.
1.7 Classes of data not allowed on this Standard
8
9
10
11
12
13
14
15
DMX512 is not an appropriate control protocol for hazardous applications, including but not limited to
Pyrotechnic Control and Scenery Mechanization.
16
17
18
19
20
This Standard makes specific but limited reference to the provision of two classes of DC power for use with
accessories and limited current remote control devices. The detailed topology and recommended cable types
for the distribution of voltage and current for use with accessories is beyond the scope of this Standard.
21
22
23
24
25
26
Compliance with this Standard is the responsibility of the manufacturer, and such markings and identification
or other claims of compliance do not constitute certification or approval by the E1 Accredited Standards
Committee. See clause 12 for Marking and Disclosure requirements and Annex E for Protocol
Implementation Compliance Statement (PICS).
27
28
29
30
31
32
See standard TIA/EIA-485 Electrical Characteristics of Generators & Receivers for Use in Balanced Digital
Multipoint Systems (ANSI/EIA-485-A-98) issued by:
Electronics Industries Alliance
Telecommunications Industry Association
2500 Wilson Boulevard
2500 Wilson Blvd., Suite 300
Arlington , VA 22201-3834 USA
Arlington, VA 22201 USA
ph: +1-703-907-7500
ph: +1-703- 907-7700 fax: +1-703-907-7727
33
34
35
36
37
38
39
40
and available from:
Data that controls any device that has a reasonable potential to cause serious physical injury
shall not be transmitted over data links built to this Standard. No one shall make, market, or sell such a
system while claiming to be DMX512 or DMX512 compatible or any similar such wording.
1.8 Limitations
1.9 Compliance
1.10 Cross Reference
Global Engineering Documents
15 Inverness Way East
Englewood, CO 80112 USA
Phone: +1-800-854-7179
Fax: +1-303-397-2740
This standard will be referred to as EIA-485 in this document.
–4–
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
2 Electrical Specifications and Physical Layer
2
2.1 General
3
4
5
6
7
8
9
10
11
12
13
14
Except where specifically called out in this document the electrical specifications of this Standard are those of
EIA-485. Where a conflict between EIA-485 and this document exists, this document is controlling as far as
this Standard is concerned.
15
16
17
18
19
20
21
EIA-485 makes no general provisions for electrical isolation. However, this Standard does, and suitable
optical isolation, transformer isolation, or other means may be employed to prevent the undesirable
propagation of voltages which exceed the Common Mode limits of EIA-485 (see clauses 3 and 4). The
inclusion of such isolation does not, however, alter the requirement that a transmitter or receiver conform to
EIA-485.
22
23
24
25
This Standard and EIA-485 make no general provisions for Electro Magnetic Compatibility (EMC) emissions
or immunity or other regulations to which manufacturers may be obligated to conform.
26
27
28
29
30
31
32
33
34
35
36
37
38
39
A data link shall consist of a single differential line driver, a terminated transmission line and one or more
differential line receivers. The transmission line shall be a data cable with a nominal characteristic
impedance of between 100 to 150 ohms as specified in clause 11. The differential drivers and receivers shall
meet the requirements of EIA-485 and all additional requirements of this Standard.
40
41
42
43
44
Various paragraphs of clause 3 deal with shield earth grounding topologies. In all cases there shall be a low
impedance connection between Pin 1 of the DMX512 port and signal common of the EIA-485 driver or
receiver circuitry. The impedance of this path shall not be greater than 100 ohms. Note that in some cases,
this impedance is limited to 0.2 ohms, and is often zero ohms.
The physical layer of a DMX512 data link is constrained by earth grounding practices, termination methods,
signal levels, EMC, EMI, protection against ESD, and accidental damage by connection to other devices.
Equipment designers shall pay particular attention to EIA-485 requirements for line drivers, line receiver
design, line voltage levels, line loading, and the Common Mode requirements of EIA-485. Further, equipment
designers must comply with the non EIA-485 requirements of clauses 3 and 4.
2.2 Electrical isolation
2.3 EMC compliance
2.4 Topology
At any time only one driver shall connect to the data link. There are no general provisions in the software
protocol for controlling switching between multiple data link drivers.
This version of the Standard provides for a defined means of returning data from dimmers and other devices
to a console, status monitor or other device, using a secondary EIA-485 data link. The particular
requirements relating to topology and termination of the secondary data link used for this facility are
described in detail in Annex B.
2.5 Data link common and grounding topologies
–5–
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
2.6 Preferred method of earth grounding data link common
2
3
4
5
6
7
8
9
Where possible, DMX512 systems should make use of ground referenced transmitting devices and isolated
receiving devices. This approach provides for a single point solid ground/chassis connection at the source,
and allows for variations in building ground potentials between transmitting and receiving devices. This is to
ensure that interoperability of equipment is achieved in situations that do not in their own right constitute a
safety hazard, but might otherwise exceed the Common Mode limitations of EIA-485. See EIA-485
clause 4.5.2.
2.7 Data termination procedures
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
DMX512 data links should be terminated to eliminate ringing and signal reflection which can cause
mis-operation of an otherwise properly designed system.
36
37
38
39
40
A DMX512 port shall always provide for a primary data link with signals as defined in clauses 5 though 7.
Provision may optionally be made for a secondary data link, a talkback data link or for limited current DC
power.
41
42
43
44
45
Terminals and connector contacts are referred to as Pins in this Standard. Where the use of a particular style
of connector is required by this Standard, pinout details are fully specified. Each DMX512 port on a device
shall reference its functionality of Pins 4 and 5 by means of the designations detailed in table 2.8.2.1. Data
link common is Pin 1, and the primary data link is defined on Pins 2 and 3.
In most systems utilizing equipment claiming compliance with this Standard, the driver will be placed at one
extremity of the data link used (cable). However, this is not mandatory. If the driver is placed at one
extremity of the data link, the driver end of the data link need not be terminated. If the driver is placed at any
point other than at the extremity, then the driver shall not be terminated and both extremities of the
transmission line shall be terminated with networks matching the characteristic impedance of the line.
Manufacturers of receiving devices may provide internal termination of the data link. Where such termination
is provided, it shall comply with the electrical and marking requirements of this Standard.
The termination topology shall be AC, rather than the DC model of earlier revisions of this Standard. AC
termination networks shall consist of a series RC network. The resistance shall be equal to the characteristic
impedance of the transmission line – 120 Ohms in series with 0.047µF. Termination components shall be
chosen to withstand continuous voltages of at least 30 VAC/42 VDC. Provision of AC termination shall be
declared as part of the TYPE mark as defined by clause 12.4 of this Standard.
To comply with this Standard, all equipment connected to a DMX512 data link shall operate in accordance
with the stated manufacturer’s specification when the data link is terminated with an external legacy DC
model terminator (100-120 Ohms between Data + and Data-).
Unpowered connected DMX512 devices shall not degrade the performance of the DMX512 transmission
system.
2.8 Port designations
2.8.1 Pin reference
–6–
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
2.8.2 TYPE classifications
2
3
4
5
6
7
A DMX512 port shall be classified as belonging to one of seven types listed in table 2.8.2.1.
Table 2.8.2.1 - TYPE classifications for DMX512 equipment
TYPE
TYPE
0
8
9
TYPE
10
11
TYPE
12
13
TYPE
14
15
TYPE
16
17
TYPE
18
19
TYPE
20
21
22
23
24
25
26
27
28
29
30
31
1
2
3
4
5
6
Symbol
Description
unidirectional DMX512 data Pins 2, 3 ONLY
(EIA-485 levels)
Comment
no connection to Pins 4,5
unidirectional DMX512 data Pins 2, 3 (EIA-485 levels)
AND loop-through on Pins 4, 5
direct wire or link connection of Pins 4 and
Pins 5 on looping in/out connection. No
other internal connection to these pins
allowed.
Two universes of DMX512
unidirectional DMX512 data Pins 2, 3 and
unidirectional DMX512 data Pins 4, 5 (EIA-485 levels)
1+
unidirectional DMX512 data Pins 2, 3 and return
signals on Pins 4, 5 in accordance with talkback
protocol as defined in Annex B
Interconnection of equipment of TYPE 3
has specific topology restrictions
unidirectional DMX512 data Pins 2, 3 (EIA-485 levels)
and any other signals on Pins 4, 5 using EIA-485
levels
unidirectional DMX512 data Pins 2, 3 (EIA-485 levels)
and NON-EIA-485 300 mA max current limited signals
not exceeding -0 VDC / +12 VDC nominal tied to both
Pins 4 & 5, and/or receiving devices that tie Pin 1
directly to Protective Ground.
Test Equipment capable of transmitting and/or
receiving and evaluating DMX512 data on Pins 2, 3.
Characteristics of Pins 1, 4, 5 not defined
refer to manufacturers instructions
Voltage on these pins must not cause
damage to legacy equipment – see
clause 3 for restrictions on implementing
TYPE 5 product; refer to manufacturers
instructions
refer to manufacturers instructions; note
that in some operation modes, other parts
of this Standard may not be adhered to
Note: References to unidirectional data are with respect to a transmitting device.
Different physical ports on a product may be of different TYPEs.
FPN: For example, a lighting controller may have two TYPE 0 ports and a TYPE 3 port; an entry level
6-way dimmer pack may have a single TYPE 0 port, or it may have a TYPE 5 port because it provides
DC power to feed an entry level controller.
A concession to provide for 24 VDC accessory power requires the use of an alternate connector and is limited
to products with only a primary data link. See clauses 9.1 and 10.4.
–7–
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
Table 2.8.2.2 - Signal designations summary
Pin
Reference
within
Standard
Legacy
Product
TYPE 0
TYPE 1
TYPE 2
TYPE 3
TYPE 4
TYPE 5
2
Common
(Screen)
Data 1-
Common
(Screen)
Data 1-
Common
(Screen)
Data 1-
Common
(Screen)
Data 1-
Common
(Screen)
Data 1-
Common
(Screen)
Data 1-
Common
(Screen)
Data 1-
3
Data 1+
Data 1+
Data 1+
Data 1+
Data 1+
Data 1+
Data 1+
4
various
Data 2-
Talkback - various
Data 2-
12 VDC
300 mA
limited
5
various
no
Loopconnection through
(passive
link)
no
Loopconnection through
(passive
link)
Data 2+
Talkback + various
Data 2+
12 VDC
300 mA
limited
2
Function
3
4
5
6
Data Link
Common
Primary
Data Link
1
7
8
9
10
11
12
Secondary
Data Link /
Talkback /
Limited
Current
Supply
13
14
15
16
17
18
WARNING: While the generic reference to Pins 1- 5 correlates to the physical pinout used on the XLR style
connectors as defined in clause 10 of this Standard, there are other situations where different physical
pinouts may be encountered
2.9 Talkback
19
20
21
22
23
24
25
TYPE 3 systems use the standard talkback scheme as defined in Annex B.
26
27
28
29
30
31
The TYPE classification of ports on products compliant with this Standard provides for a consistent means of
predicting and utilizing features which were not clearly identified in earlier revisions of the Standard.
Manufacturers will be required to mark and make available basic information about their products in
accordance with clause 12.
32
33
34
35
36
37
DMX512 transmitting and receiving devices may be galvanically isolated. Should a transmitting or receiving
device be galvanically isolated, it shall comply with the protection requirements defined by this Standard.
FPN: Products with other talkback schemes are permissible and would fin into the TYPE 4 classification.
However, no level of cross-manufacturer interoperability of TYPE 4 talkback schemes could be
assumed from compliance with this Standard.
2.10 Device interconnection
2.12 Galvanic isolation from protective ground
This Standard defines particular grounding and galvanic isolation topologies which must be followed in order
to allow the use of the term “isolated” within the port TYPE mark. These topologies are described in clause 3.
–8–
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
3 Nominal Operating Characteristics
2
3.1 General
3
4
5
6
Operation limits generally follow the detailed requirements of EIA-485 for generator characteristics. Where
appropriate, separate limits are given for galvanically isolated products.
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
All electrical characteristics shall be measured at the output terminals of the product. Transmitting devices
shall deliver open circuit output voltage not less than 1.5V and not more than 6V as defined in EIA-485
clause 4.2.1
3.2 Transmitter characteristics
Transmitting devices shall comply with the requirements of EIA-485 clause 4.2.2 for differential and offset
output voltages, which requires that the magnitude of the differential output voltage be not less than 1.5V and
not more than 5V when connected to a test load of two 27 ohm resistors.
The requirements of EIA-485 clause 4.2.2 for generator offset voltage and EIA-485 clause 4.2.3 for
Differential Output voltage (Common Mode loading) shall be met.
The requirements of EIA-485 clause 4.2.4 for Off-state output current shall be met, provided that the Unit load
for the generator in the off state does not exceed 1.
Transmitting devices shall comply with the requirements of EIA-485 clause 4.2.7, for which the unit interval
(tui) shall be regarded as 4 microseconds.
In battery operated equipment or equipment which has no inherent provision for connection to protective
ground, chassis shall be deemed to be any exposed metal connector parts which do not carry signals. All
such parts shall be at equal potential.
For Isolated devices, a capacitor shall be fitted between Pin 1 and chassis for the purpose of Radio
Frequency bypass. The value of this is not mandated by the Standard, but is expected to be in the range
0.001-0.1µF.
–9–
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
2
3
4
All transmitting device outputs shall meet the following conditions in table 3.2 during normal operation under
open circuit condition.
Table 3.2 Transmitter characteristics
5
Connection
Limit
Comment
6
7
Pin 2 to Pin 1 or
Pin 3 to Pin 1
0<
_v<
_ +6 VDC
8
9
Pin 4 to Pin 1 or
Pin 5 to Pin 1
0<
_v<
_ +6 VDC
10
11
12
Pin 4 to Pin 1 or
Pin 5 to Pin 1
Pin 4 to Pin 5
+12 VDC ± 4%
current limited to 600 mA
0 (no differential allowed)
13
Chassis to any Pin
TYPE 0 - TYPE 4 Ports
Only
note 1
note 1
>
_ 22M ohm @ 42 VDC
Isolated Devices Only
Ground Referenced
Galvanically Isolated
0V
N/A
Pin 2 to Chassis or
Pin 3 to Chassis
0<
_v<
_ +6 VDC
N/A
18
19
Pin 4 to Chassis or
Pin 5 to Chassis
0<
_v<
_ +6 VDC
N/A
TYPE 0 - TYPE 4 Ports
Only
20
21
Pin 4 to Chassis or
Pin 5 to Chassis
0<
_v<
_ +12 VDC
N/A
note 1
22
Pin 2 to Pin 3
+/- 6V (open circuit)
+/- 6 V
23
Pin 4 to Pin 5
+/- 6V (open circuit)
+/- 6 V
14
15
Pin 1 to Chassis
16
17
24
25
26
27
28
29
30
31
32
33
34
35
36
note 2
Notes:
1)
This concession is ONLY available for equipment claiming compliance as TYPE 5 and marked in
accordance with the provisions of this Standard.
2)
Ground Referenced transmitting devices shall have a direct connection between Pin 1 and chassis.
3.3 Earth grounding of data link common for transmitters
In recognition of the need for DMX512 compliant product to be capable of interconnection as part of large and
potentially complex systems, this Standard defines two allowable topologies for the earth grounding of data
link common and signal common for transmitters, to be known as “Ground Referenced” and “Galvanically
Isolated”.
– 10 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
3.3.1 Ground referenced transmitters
Figure 3.3.1 - Ground Referenced Transmitter
2
3
4
5
6
7
8
9
10
11
12
13
Notes Figure 3.3.1:
1)
Output connections shall be marked in accordance with that detailed for Ground Referenced transmitter.
2)
The existence of any isolation barrier does NOT qualify output for marking as ISOLATED.
3)
Product shall be provided with provision for connection to protective earth.
4)
Pin 1 to Chassis connection shall satisfy tests as defined in clause 4.6.
5)
Manufacturers shall be permitted to fit a resistor as per clause 2.5.
3.3.2 Galvanically isolated transmitters
Figure 3.3.2 - Galvanically Isolated Transmitter
14
15
16
17
18
19
20
21
22
23
24
Notes Figure 3.3.2:
1)
Any pin of the DMX512 output shall present an impedance >
_ 22 Mohm at 42 VDC with respect to
Chassis, with respect to Protective Ground (where fitted), and with respect to any other signal inputs or
outputs.
2)
Adherence to this topology allows DMX512 transmitter connection to be marked as ISOLATED. In such
cases, the power supply for the driver electronics will be floating.
3)
Manufacturers shall be permitted to fit a resistor as per clause 2.5.
– 11 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
3.4 Receiver characteristics
2
3
4
5
6
7
8
For isolated devices, a capacitor shall be fitted between Pin 1 and chassis for the purpose of Radio
Frequency bypass. The value of this is not mandated by the Standard, but is expected to be in the range
0.001-0.1µF.
9
Devices shall continue to operate correctly when exposed to any of the conditions in table 3.4.
Table 3.4 Receiver characteristics
Connection
Limit
Comment
10
11
Pin 2 to Pin 1 or
Pin 3 to Pin 1
+12 / -7 VDC
12
13
Pin 4 to Pin 1 or
Pin 5 to Pin 1
+12 / -7 VDC
14
Common Mode range
Non-Galvanically Isolated
Galvanically Isolated
100 ohms
-Note 1-
>
_ 22M ohm @ 42 VDC
15
Pin 1 to Chassis
16
17
Pin 2 to Chassis or
Pin 3 to Chassis
+12 / -7 VDC
>
_ 22M ohm @ 42 VDC
18
19
Pin 4 to Chassis or
Pin 5 to Chassis
+12 / -7 VDC
>
_ 22M ohm @ 42 VDC
20
Pin 2 to Pin 3
+/- 6V
+/- 6 V
21
Pin 4 to Pin 5
+/- 6V
+/- 6 V
22
23
24
25
26
27
28
Any Pin to Chassis
N/A
30 VAC / 42 VDC
29
30
31
32
33
34
Note 1 : This cannot be characterized in terms of voltage. Manufacturers shall be permitted to fit a resistance of
100 ohms +/-20% between Chassis and Pin 1 for the purpose of limiting current in the screen due to small
differential ground potentials. This method provides for reduction of Common Mode voltage at the line receiver.
3.5 Earth grounding of data link common for receivers
This Standard defines several allowable topologies for earth grounding of data link common and signal
common for receiving devices. These are to be known as “non-isolated” and “isolated”. A specific concession
is available to manufacturers of non-isolated receivers who, for reasons beyond the scope of this Standard,
require a direct link between data link common and chassis.
– 12 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
3.5.1 Non-isolated receivers
Figure 3.5.1.1 - Non-Isolated Receiver
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Notes to Figure 3.5.1.1:
1)
Since 0 V is not directly referenced to Chassis, local product safety standards may restrict choice of
power supply (e.g., use of a Class 2 supply).
2)
Manufacturers shall be permitted to fit a resistor as per Note 1, Table 3.4 Receiver Characteristics.
3)
A concession to make a zero ohm connection in place of the 100 ohm resistor is available to
manufacturers who mark the associated port as grounded, using the standard symbol representation
as defined in clause 12.3. When applying this concession, the data link common (Pin 1)
to chassis connection shall satisfy the impedance tests as defined in clause 4.6 of this Standard. Unless
this concession is applied, no other connection between circuit 0V supply and chassis is permitted.
4)
Manufacturers shall be permitted to fit a resistor as per clause 2.5.
– 13 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
Figure 3.5.1.2 - Non-Isolated Receiver (other signal outputs)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
Notes to Figure 3.5.1.2:
1)
Since 0 V is not directly referenced to Chassis, local product safety standards may restrict choice of
power supply (e.g., use of a Class 2 supply).
2)
Manufacturers shall be permitted to fit a resistor as per Note 1, Table 3.4 Receiver Characteristics.
3)
A concession to make a zero ohm connection in place of the 100 ohm resistor is available to
manufacturers who mark the associated port as grounded, using the standard symbol representation
as defined in clause 12.3. When applying this concession, the data link common (Pin 1)
to chassis connection shall satisfy the impedance tests as defined in clause 4.6 of this Standard. Unless
this concession is applied, no other connection between circuit 0V supply and chassis is permitted.
4)
Where other electrical outputs are present there shall be no low impedance path between the data link
common/ signal common of the DMX512 receiver (Pin1) and such inputs or outputs including the signal
I/O common. With the common mode 100ohm 2 watt resistor removed, the impedance between data
link / signal common of the DMX512 port and any other signal I/O input or output shall be greater than
1000 ohms at 12 VDC. The removal of the resistor (or 0 ohm link as allowed in note 3) is only permitted
for the purpose of making this test.
5)
Manufacturers shall be permitted to fit a resistor as per clause 2.5.
6)
Designs using this topology shall restrict the voltage levels on all such signal inputs and outputs to be
within a 30 VAC / ±42 VDC limit.
– 14 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
3.5.2 Isolated receivers
Figure 3.5.2 - Isolated Receiver
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Notes Figure 3.5.2:
1)
Any pin of the DMX512 input shall present an impedance >
_ 22 Mohm at 42 VDC with respect to
Chassis, with respect to Protective Ground (where fitted), and with respect to any other signal inputs or
outputs.
16
17
18
19
20
This configuration is not permitted, although it may exist on some legacy products. While this topology is
described as one possible topology in EIA-485, it is not appropriate when considering operation of DMX512
receiving devices in systems encountering differential ground potentials.
2)
Adherence to this topology allows DMX512 receiver connection to be marked as ISOLATED. In such
cases, the power supply for the receiver electronics will be floating
3)
Manufacturers shall be permitted to fit a resistor as per clause 2.5.
4)
Manufacturers may connect the “Other Electronics 0 V line to chassis or protective earth at their
discretion.
3.5.3 Disallowed receiver topologies
Figure 3.5.3 - Receiver Topology NOT Allowed
– 15 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
3.6 Earth grounding of data link common for other devices (signal processors)
2
3.6.1 Processing devices – floating
3
4
5
6
7
8
9
10
11
This Standard defines two allowed topologies for the earth grounding of data link common applicable to
DMX512 Processing devices. These shall be known as “Floating” and “Ground Referenced”. It is also
permissible to design processing devices based on the Isolated Receiver / Ground Referenced Transmitter or
Isolated Receiver / Isolated Transmitter models already described.
As an aid to clarity and in order to minimize confusion with other schemes known to exist in legacy products,
several topologies are specifically excluded. Manufacturers choosing to continue with the use of such
topologies will be unable to claim compliance with this revision of the Standard.
Figure 3.6.1- DMX512 Processing Device, Floating
(Allowed)
12
13
14
15
16
17
18
19
20
21
Notes Figure 3.6.1:
1)
Any input or output pin shall present an impedance >
_ 22 Mohm at 42 VDC with respect to Chassis, and
with respect to Protective Ground (where fitted).
2)
In operation, the grounding of a device using this topology is determined by the other DMX512 devices
that it is connected to.
3)
Manufacturers shall be permitted to fit a resistor as per clause 2.5.
– 16 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
3.6.2 Processing devices – ground referenced
Figure 3.6.2 - DMX512 Processing Device, Grounded
(Allowed)
2
3
4
5
6
7
8
9
10
11
12
13
Notes Figure 3.6.2:
1)
A DMX512 processing device accepting electrical non-DMX512 inputs and providing one or more
DMX512 outputs may ground the DMX512 output commons if it meets all the requirements shown for
figure 3.3.1.
2)
Output connections shall be marked in accordance with that detailed for Ground Referenced DMX512.
3)
Pin 1 to Chassis connection shall satisfy tests as defined in clause 6.
4)
Manufacturers shall be permitted to fit a resistor as per clause 2.5.
3.6.3 Processing devices – grounded
Figure 3.6.3 - DMX512 Processing Device, Grounded
(Only Allowed when Marked
)
14
15
16
17
18
19
Notes Figure 3.6.3:
1)
A DMX512 processing device accepting a DMX512 input and providing one or more non-DMX512
outputs may ground the DMX512 input common if it meets all the requirements shown for a non-isolated
receiver (other signal outputs) as detailed in figure 3.5.1.2, including the marking requirements of note 3.
2)
Manufacturers shall be permitted to fit a resistor as per clause 2.5.
– 17 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
3.6.4 Disallowed processing device topologies
Figure 3.6.4.1 - DMX512 Processing Device, Non-Floating
(Not Allowed)
2
3
4
5
Notes Figure 3.6.4.1:
1)
This configuration is not permitted (although it may exist on some legacy products). This topology is
contradictory to the requirements of Figure 3.3.1, Note 4.
Figure 3.6.4.2 - DMX512 Processing Device, Grounded
(Not Allowed)
6
7
8
9
10
Notes Figure 3.6.4.2:
1)
Grounding of the common is not allowed in a DMX512 processing device accepting one or more
DMX512 inputs while simultaneously providing one or more DMX512 outputs.
11
12
13
14
15
16
17
18
The maximum number of devices permitted on a DMX512 data link is 32. Transmitters designed for this
Standard shall be capable of driving 32 devices on a DMX512 data link. All DMX512 devices shall have a
unit load of 1or less.
3.7 Loading designation
A receiver biased to any voltage from -5 to +10 volts shall not present a capacitive load to the line of more
than 200pf. If this value is frequency dependent, the value given shall be the capacitive load when driven by
a 650kHz sine wave.
– 18 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
4 Protection
2
4.1 General
3
4
5
6
7
To comply with this Standard, transmitting and receiving devices shall be protected against accidental
connection of the data link to voltages beyond the range normally encountered for EIA-485 systems, in
accordance with clauses 4.4 (DMX512 Transmitter Protection) and 4.7 (DMX512 Receiver Protection).
4.2 Minimum Electro Static Discharge (ESD) protection
8
9
10
11
12
Manufacturers shall ensure that any pins can withstand a minimum of 8KV ESD in accordance with the
corresponding human body model as defined in EN61000-3-2 or other local regulations which may require
higher levels of protection.
13
14
15
16
17
18
19
20
21
22
23
24
25
Clause 4.2 of the EIA-485 specification recognizes that certain other extraneous conditions may overstress
the system and that these conditions should be specified in the referencing standard. Extensive use of
temporary and portable equipment in Entertainment Lighting industry results in frequent connection and
disconnection of equipment and gives rise to the possibility of equipment misconnection. Protection levels in
excess of those defined in EIA-485 is required as detailed below.
4.3 Minimum protection against interconnection damage
To comply with this Standard, equipment shall be protected against damage resulting from accidental
connection to voltages in excess of the minimum defined in EIA-485 clauses 4.2.5 and 4.2.6. Separate
specification is provided for transmitting devices (Ground Referenced, Isolated, Floating) and receiving
devices (Non-isolated, Isolated and Floating). This does not negate the need to comply with EIA-485 clause
4.2.6 - Transient overvoltage tolerance.
– 19 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
2
3
4
5
6
7
8
9
10
11
4.4 DMX512 Transmitter protection
Driver current limiting shall be in conformance with the requirements of EIA-485 clause 4.2.5. With the
transmitting device output terminals shorted together, the transmitting device shall not be damaged.
In battery operated equipment, chassis shall be deemed to be any exposed connector parts which are metal
and not carrying signals.
Transmitters shall not be damaged by voltages less than or equal to those listed in table 4.4 for both the
power-on and power-off conditions.
Table 4.4 Transmitter protection
12
Connection
13
14
Pin 2 to Pin 1 or
Pin 3 to Pin 1
30 VAC / ± 42 VDC
15
16
Pin 4 to Pin 1 or
Pin 5 to Pin 1
30 VAC / ± 42 VDC
17
Pin 2 to Pin 3
30 VAC / ± 42 VDC
18
Pin 4 to Pin 5
30 VAC / ± 42 VDC
19
Minimum Protection Limit
Comment
Not applicable
to TYPE 5 ports
Ground Referenced
Galvanically Isolated
Floating
-Note 1-
20
Pin 1 to Chassis
Must Pass Earth
Continuity Test
N/A
N/A
21
22
Any other Pin to
Chassis
30 VAC / ± 42 VDC
N/A
N/A
23
24
25
26
27
28
29
Any Pin to
Chassis
N/A
30 VAC / ± 42 VDC
30 VAC / ± 42 VDC
See clause 4.5
Note 1 : Floating heading to indicate that this is only encountered on DMX512 Processing equipment.
4.5 Earth continuity for ground referenced transmitters
30
31
32
33
The resistance of the connection between the protective earth terminal or chassis and Pin 1 shall not exceed
0.2 ohms. Compliance with this shall be as per the test described in clause 4.6.
34
35
36
37
38
The test shall be carried out for 1 minute with a test current of not less than 10 amps A.C. or D.C. The
voltage drop between the protective earth terminal or chassis and Pin 1 shall be measured and the resistance
calculated from the current and this voltage drop. This test shall not be required as a routine manufacturing
test.
4.6 Data link common earth continuity test
– 20 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
4.7 Receiver protection
2
3
4
5
6
7
A capacitor shall be fitted between Pin 1 and chassis for the purpose of Radio Frequency bypass. The value
of this is not mandated by the Standard, but is expected to be in the range 0.001-0.1µF
8
Receivers shall not be damaged by voltages less than or equal to those listed in table 4.7.
Table 4.7 Receiver protection
Connection
Minimum Protection Limit
9
10
Pin 2 to Pin 1 or
Pin 3 to Pin 1
30 VAC / ± 42 VDC
11
12
Pin 4 to Pin 1 or
Pin 5 to Pin 1
30 VAC / ± 42 VDC
13
Pin 2 to Pin 3
30 VAC / ± 42 VDC
14
Pin 4 to Pin 5
30 VAC / ± 42 VDC
Non-Galvanically
Isolated
15
Galvanically Isolated
Comment
Not applicable
to TYPE 5 ports
Floating
-Note 2-
16
Pin 1 to Chassis
-note 1-
N/A
N/A
17
18
Any other Pin to
Chassis
30 VAC / ± 42 VDC
N/A
N/A
19
20
21
22
23
24
25
26
27
28
29
30
31
Any Pin to
Chassis
N/A
30 VAC / ± 42 VDC
100Mohm at 50 VDC
30 VAC / ± 42 VDC
>
_ 22Mohm at 50 VDC
Note 1: This cannot be characterized in terms of voltage. Clause 3.4 (Receiver Characteristics) allows
manufacturers to fit a resistance between chassis and Pin 1 for the purpose of limiting the current in the
screen (shield) due to small ground differentials. Any such resistance shall survive continuous
connection to voltages within the EIA-485 Common Mode range of -7/+12 VDC. Manufacturers shall
ensure that any failure of this component due to exposure to voltages not exceeding 30 VAC / 42 VDC
will not cause a safety hazard.
Note 2: Floating heading to indicate that this is only encountered on DMX512 Processing equipment.
4.8 Connection integrity
32
33
34
35
The link between input port data link common and loop-through port data link common (Pin 1) shall not be
damaged by currents in the range 0 - 1 ampere over the voltage range 0-+12 VDC.
36
37
38
39
40
41
42
The link between input port Pin 4 and output port Pin 4 of a TYPE 1 device shall not be damaged by currents
in the range 0 - 1 ampere over the voltage range 0-+12 VDC.
4.8.1 TYPE 1 ports - additional requirements
The link between input port Pin 5 and output port Pin 5 of a TYPE 1 device shall not be damaged by currents
in the range 0 - 1 ampere over the voltage range 0-+12 VDC.
– 21 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
4.8.2 TYPE 5 ports - additional requirements
2
3
4
5
6
7
8
9
Where a TYPE 5 port makes limited current power available the power source shall not be damaged by
continuous short circuit to any other pin.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Where a TYPE 5 product makes the limited current supply available on both an input or output port and
corresponding loop or through port, the manufacturer shall ensure that the total current that can flow from any
port is limited to 600mA even when the product is connected to other TYPE 5 devices.
4.9 Connection integrity - products with accessory power
For products using Accessory Power (and the prescribed 4 pin XLR connector as per clause10.4) the link
between input port data link/power common and loop-through port data link/power common (Pin 1) shall not
be damaged by currents in the range 0 - 5 amperes over the voltage range 0 - +25 VDC.
For products using Accessory Power (and the prescribed 4 pin XLR connector as per clause 10.4) the link
between input port +24 VDC and loop-through port +24 VDC (Pin 4) shall not be damaged by currents in the
range 0 - 5 amperes over the voltage range 0 - +25 VDC.
FPN : There are fundamental differences between TYPE 5 products and products using Accessory
power. Unlike limited current (TYPE 5) devices, there is no requirement to limit the through current on
Pin 4. For products supplying Accessory Power, and claiming compliance with this Standard, the
current available at +24 VDC shall be current limited to not more than 5 Amps. The risk of accidental
interconnection of devices using Accessory power with other DMX512 products is removed by the use
of the 4 pin XLR connector as detailed in clause 10.4.
– 22 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
5 Data Protocol
2
5.1 Format
3
4
5
6
7
8
Data transmitted shall be in asynchronous serial format. DMX512 slots shall be transmitted sequentially,
beginning with slot 1 and ending with the last implemented slot, up to a maximum of 512. Prior to the first slot
being transmitted, a Reset Sequence shall be transmitted – a Break signal, followed by a MARK AFTER
BREAK, and a properly framed START Code. Valid DMX512 slot values shall be 0 to 255 decimal.
9
10
5.2 Frame format
The data transmission format for each data value transmitted shall be as follows:
11
BIT POSITION
DESCRIPTION
12
1
Start Bit, Low or SPACE
13
2 through 9
Slot Value Data Bits, Least Significant Bit to Most
Significant Bit Positive logic
14
10, 11
Stop Bits, High or MARK
15
16
17
Parity
Not transmitted
5.3 Packet format
18
19
20
21
The format of a DMX512 packet shall be a Reset Sequence followed by up to 512 slots of data. A packet is
separated from the next packet by a Mark Before Break.
22
23
24
25
26
27
28
The Break signal (Timing Diagram, Designation #1) may be of any length and shall last 88 microseconds (two
frame times) duration or longer. A BREAK shall be defined as a high-to-low transition followed by a low of at
least 88 microseconds. All receiving devices shall interpret any such BREAK as a terminator for any pending
transmission/data packet and its end as the start of the MARK AFTER BREAK and START Code sequence at
the beginning of the next packet.
29
30
31
32
33
34
35
36
The duration of the MARK separating the BREAK and the START Code (Timing Diagram, Designation #2)
shall be not less than 8 microseconds and not greater than 1 Second. All DMX512/1990 or later transmitters
shall produce a MARK AFTER BREAK of not less than 8 microseconds. All receivers shall recognize an
8 microsecond MARK AFTER BREAK. Receivers capable of also recognizing the shorter 4 microsecond
MARK AFTER BREAK (as specified in the 1986 version of this Standard) may be identified and marked as
having this capability as per clause 12.1.
37
38
39
40
The START Code is the first properly framed byte following a BREAK. The START Code identifies the
function of subsequent data in that packet.
41
42
The NULL START Code shall be defined as a properly framed NULL byte (all zeros) following a BREAK. The
NULL START identifies subsequent data as sequential 8-bit information.
5.4 Break signal
5.5 Mark After Break
5.7 START Code
5.7.1 NULL START Code
– 23 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
5.7.2 Other START Codes
2
3
4
5
All other START Codes (1 through 255 decimal, 01 through FF hexadecimal) are referred to as Alternate
START Codes. See clause 6 and Annex A.
6
7
8
9
Each data link shall support up to 512 slots. Multiple links shall be used where larger numbers of slots are
required.
5.8 Maximum number of slots
5.9 Minimum number of slots
10
11
12
13
There shall be no minimum number of slots on the data link. DMX512 data packets with fewer than 512 slots
may be transmitted, provided that the conditions of this Standard, including all of clause 5, are observed.
14
15
16
17
18
19
The time between any two frames of a data packet (Timing Diagram, Designation #9) may vary between
0 microseconds and 1 Second. The line must remain in a "marking" state during any such idle period. A
receiver must be capable of accepting a data packet having no idle time (0 microseconds) between any of its
frames.
20
21
22
23
24
25
26
27
28
Every data packet transmitted on the data link, regardless of START Code or length, must begin with a
BREAK, MARK AFTER BREAK, and START Code sequence as defined above. The time between the
second stop bit of the last data byte/frame of one data packet and the falling edge of the beginning of the
BREAK for the next data packet (Timing Diagram, Designation #10) may vary between 0 microseconds and
1 Second. The line shall remain in an idle ("marking") state throughout any such period greater than
0 microseconds. Transmitters, therefore, shall not produce multiple BREAKs between data packets.
Receivers, however, shall be capable of recovering from multiple BREAKs produced by data link line errors.
29
30
31
32
The period between the falling edge at the start of any one BREAK shall be not less than 1196 microseconds
from the falling edge at the start of the next BREAK.
33
34
35
36
37
38
Valid dimmer levels shall be 0 to 255 decimal (00 to FF hexadecimal) representing dimmer control input.
0 shall represent a dimmer output of OFF or minimum and 255 shall represent an output of FULL. A dimmer
shall respond to increasing the DMX512 slot level for 0 to 255 by fading from its minimum level (off) to its
maximum level (full). The exact relationship between DMX512 slot levels and dimmer output is beyond the
scope of this Standard.
5.10 Defined line state between frames
5.11 Defined line state between data packets (Mark Before Break)
5.12 Minimum Break spacing
5.13 Dimmer class data
– 24 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
5.14 Timing Diagram
Figure 5.14 - Timing Diagram
2
Designation
Description
Min
Typical
Max
Unit
3
-
Baud Rate
245
250
255
kbaud / sec
4
-
Bit Time
3.92
4
4.08
µsec
5
-
Minimum Update Time for 512 slots
–
22.67
–
mS
6
-
Maximum Update Rate for 512 slots
–
44.11
–
/ Sec
7
1
“SPACE” for BREAK
88
–
–
µsec
8
2
“MARK” After BREAK (MAB)
8
–
1
µsec
sec
9
3
FRAME Time
43.12
44
44.88
µsec
10
4
START Bit
3.92
4
4.08
µsec
11
5
LEAST SIGNIFICANT DATA Bit
3.92
4
4.08
µsec
12
6
MOST SIGNIFICANT DATA Bit
3.92
4
4.08
µsec
13
7
STOP Bit 1
3.92
4
4.08
µsec
14
8
STOP Bit 2
3.92
4
4.08
µsec
15
9
“MARK” Time between FRAMES
0
–
1
sec
16
10
“MARK” Before BREAK (MBB)
0
–
1
sec
17
11
BREAK to BREAK Time
1196
–
–
1.025
µsec
sec
18
19
12
RESET Sequence (BREAK, MAB, START Code)
139.12
–
–
µsec
– 25 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
6 Alternate START Codes
2
6.1 Other Optional START Codes
3
4
5
6
7
8
9
10
11
12
13
14
15
In order to provide for future expansion and flexibility, this Standard makes provision for 255 additional
START Codes (1 through 255 decimal, 01 through FF hexadecimal), henceforth referred to as Alternate
START Codes. For this reason, a dedicated NULL START Code receiver must not accept as 8-bit level data
any data packet with a START Code other than NULL START following the BREAK. See Annex A for
Alternate START Code and Manufacturer/Organization ID Registration Policies and designations of Reserved
Alternate START Codes.
16
6.2.1 ASC timing parameters
17
18
19
20
21
22
23
Regardless of the function resulting from the Alternate START Code, DMX512 parameters not specifically
modified when an Alternate START Code is implemented, shall be adhered to, including the following:
MINIMUM BREAK DURATION (clause 5.12), TIMINGS as defined in the TIMING DIAGRAM (clause 5.14),
and LOSS OF DATA TOLERANCE (clause 8), and a maximum of one START Code and 512 slots
(513 frames) per packet.
24
25
26
27
A DMX512 transmitter interleaving NULL START Code packets with Alternate START Code packets shall
send a NULL START Code packet at least once per second.
28
29
30
31
For any packet containing an Alternate START Code, the packet to packet timing requirements of this
Standard shall be modified as follows:
32
33
34
35
36
37
For DMX512 originating transmitters such as consoles, show controller, and protocol bridges, the time from
the beginning of the Alternate START Code to the beginning of the START Code of the next packet shall be
not less than 110% of the time required to send the Alternate START Code packet with the minimum allowed
Break, Mark After Break, and frame timings.
38
39
40
41
42
43
44
45
DMX512 processing devices or any device that receives and re-transmits DMX512 shall as nearly as possible
maintain START Code to START Code timing as defined above to not less than 110% of the time required to
send that packet with the minimum allowed Break, MAB and frame timings. They may modify this time to
accommodate baud rate tolerances while assuring that no Alternate START Code packets that they are
designed to relay are lost.
Alternate START Code CF hexadecimal (207 decimal) is reserved for a System Information Packet (see
clause 7 for description), Alternate START Code 55 hexadecimal (85 decimal) is reserved for a special Test
Packet (see clause 6.6 for description), and Alternate START Code 17 hexadecimal (23 decimal) is reserved
for a special text packet (see clause 6.7 for description).
6.2 Alternate START Code format
6.2.2 ASC refresh interval
6.2.3 ASC packet spacing
6.2.3.1 ASC originating transmitters
6.2.3.2 ASC in-line transmitters
In all cases the minimum Break to Break spacing set in clause 5.12 of this Standard shall also be adhered to.
– 26 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
6.5 Handling of Alternate START Code packets by in-line devices
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
DMX512 processing devices or any device that receives and re-transmits DMX512 wishing to claim
conformance to this Standard shall state in the manual for the product how they process Alternate START
Code packets. The acceptable processing methods are:
22
23
24
25
26
27
28
29
Alternate START Code 55h (85 decimal) shall designate a special test packet of 512 slots, where all slots
carry the value 55h (85 decimal). Test packets shall be sent so that the time from the start of the Break until
the stop bit of the 512th slot shall be no more than 25 milliseconds. When test packets are sent back to back,
the Mark Before Break time shall be no more than 88 microseconds. The Break timing for test packets shall
be greater than or equal to 88 microseconds, and less than or equal to 120 microseconds. The Mark After
Break time shall be greater than or equal to 8 microseconds and less than or equal to 16 microseconds.
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
Alternate START Code 17h (23 decimal) shall designate a special packet of between 3 and 512 slots. The
purpose of the ASC text packet is to allow equipment to send diagnostic information formatted for display.
1) Block all packets containing particular Alternate START Codes. The START Codes blocked must
be listed.
2) Pass unmodified all packets containing particular Alternate START Codes. The START Codes
passed must be listed.
3) Process the information contained in packets containing particular Alternate START Codes.
Optionally creating new packets containing Alternate START Codes. The processing algorithm must
be appropriate for use intended for this START Code. The algorithm must be stated in enough detail
to allow the user to decide if the device will satisfy their needs.
DMX512 in line repeating transmitters wishing to claim conformance to this Standard shall not pass some
packets with a particular Alternate START Code while blocking other packets containing the same Alternate
START Code unless doing so as part of a stated processing algorithm.
6.6 ASC test packet
6.7 ASC text packet
Slot allocation is as follows:
Slot 1: Address of text viewer. A value of zero allows any DMX512 capable viewer to display the
text. Values in the range 1-255 allow for addressing of text messages.
Slot 2: Characters per Line. Indicates the number of characters per line that the transmitting device
has used for the purposes of formatting the text. A value of zero indicates ignore this field.
Slot 3-512: Consecutive display characters in ASCII format. All characters are allowed and where a
DMX512 text viewer is capable, it shall display the data using the IBM standard character set.
When the ASC text packet is transmitted as part of the normal operation of a product, it shall be transmitted
no more frequently than one packet per 256 packets of NULL START Code. When the ASC text packet is
transmitted in a special diagnostic mode of the product, it may be transmitted continuously.
– 27 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
7 System Information Packet (SIP) Alternate START Code
2
7.1 System Information Packet (SIP)
3
4
5
6
Alternate START Code CF hexadecimal is reserved for a System Information Packet (SIP). The SIP provides
(but is not restricted to) a means of sending checksum data relating to the previous packet on the data link.
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
7.2 SIP format
The format of the SIP is as Follows:
SIP Format - START Code = CFh (207 decimal)
Slot 1
Slot 2
Slot 3
Slot 4
Slot 5
Slot 6
Slot 7
Slot 8
Slot 9
Slot 10
Slot 11
Slot 12
Slot 13
Slot 14
Slot 15
Slot 16
Slot 17
Slot 18
Slot 19
Slot 20
Slot 21
Slot 22
Slot 23
Slot 24
Control Bit Field
refer Clause 7.3
MSB of Optional 16 bit additive Checksum of previous packet
8 bit additive or the LSB of the Optional 16 bit Checksum of previous packet
SIP sequence number
DMX512 universe number
refer Clause 7.6
DMX512 processing level
refer Clause 7.7
Version of Software sending this SIP
refer Clause 7.8
Standard Packet Len MSB
Standard Packet Len LSB
refer Clause 7.9
Number of Packets transmitted by originating device since last SIP MSB
Number of Packets transmitted by originating device since last SIP LSB
Originating Device’s Manufacturer ID MSB
Originating Device’s Manufacturer ID LSB
refer Clause 7.11
Last Device’s Manufacturer ID MSB
Last Device’s Manufacturer ID LSB
1st Predecessor to Last Device’s Manufacturer ID MSB
1st Predecessor to Last Device’s Manufacturer ID LSB
2nd Predecessor’s Device Manufacturer ID MSB
2nd Predecessor’s Device Manufacturer ID LSB
3rd Predecessor’s Device Manufacturer ID MSB
3rd Predecessor’s Device Manufacturer ID LSB
reserved for future use
reserved for future use
Checksum of the SIP
Equipment that implements SIPs shall be required to transmit them at least once every 15 seconds.
7.3 Control bit field
38
d7
d6
d5
d4
d3
d2
d1
d0
39
40
41
42
43
44
45
46
47
48
1 = LSB
checksum
exists
1=MSB
checksum
exists
reserved
transmit as
0
reserved
transmit as
0
reserved
transmit as
0
reserved
transmit as
0
reserved
transmit as
0
set=1
control bit
Processing of the Control Bit is optional. If implemented, when the Control Bit is set (=1), the subsequent
NULL START Code packet shall be held pending the reception of the next SIP for validation of the checksum.
If a second NULL START Code packet is received without a preceding SIP, the receiver shall return to an
immediate use mode and flag this as an error condition.
– 28 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
7.4 Checksums
2
3
4
5
6
8 bit additive checksum (or optional 16 bit additive checksum) of all frames in the previous packet. The
checksum includes the START Code frame. Bits must be set in the control bit field to indicate which type of
checksum is being sent.
7.5 SIP Sequence number
7
8
9
10
A free running 8 bit counter identifying the SIP and incremented by a SIP generator by 01h on every
subsequent SIP. This field may be checked to ensure that SIPS are not being dropped randomly.
11
12
13
14
This slot indicate the (originating) DMX512 universe currently transmitted on this link. 00h is not used. Valid
values 01h - FFh (1 decimal - 255 decimal).
15
16
17
18
19
20
21
This slot indicates the level of post console processing. Originating devices shall always transmit a value of
00h in this field. Processing devices such as merge units or any that regenerate or provide a media
conversion (e.g., Ethernet to DMX512) facility shall increment the value of this field by 01h. The content of
this field indicates a level of process “hops” that data on the link has been subjected to relative to the
originating transmitting device.
22
23
24
25
26
27
28
7.6 Originating universe
7.7 DMX512 processing level
7.8 Software version
00h
01h - FFh
not implemented
firmware version of last device
FPN: This slot for use by the manufacturer and may not correlate with any formally published release
identifier.
7.9 Packet lengths
29
30
31
32
33
34
35
36
37
This declares the standard length of packets for START Code 00, normally transmitted on this link.
Valid values are
0000h
packet length not declared
0001h - 0200h designates value of fixed packet length
0201h - 7FFFh are not used
8000h
Dynamic Packet, length not declared
8001h - 8200h length of last dynamic packet
8201h - FFFFh are not used
38
39
40
41
A 16 bit count of the number of packets transmitted by the originating device since last SIP was transmitted.
This count should not increment past FFFFh.
7.10 Number of packets
– 29 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
7.11 Manufacturer ID
2
3
4
5
6
7
8
9
Manufacturer ID will be the same 16 bit assignment as used for the Manufacturer’s ID field used with
Alternate START Code 91h (see Annex A - clause A4.2).
an ID == 0000h indicates that Manufacturer is not declared.
an ID == FFFFh indicates that Manufacturer has applied for, but not been granted, and ID and that this
transmission originates from a product under development.
7.12 Packet history
10
11
12
13
14
15
16
17
18
19
Specialist DMX512 Processing devices and media converters shall be required to insert their own
Manufacturers ID into the next available SIP slot. An originating device shall always send its Manufactures ID
in SIP slots 12 and 13, with 0000h in slots 14, 15; 16, 17; 18, 19 and 20, 21. The next downstream
processing device shall insert its own Manufacturers ID into slots 14, 15. The next+1 downstream processing
device shall insert its own Manufacturers ID into slots 16, 17 and so on.
20
21
22
8 bit additive checksum of the SIP START Code (CFh) and first 23 slots of SIP data.
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
Manufacturers of control consoles are encouraged to transmit SIPs, either as a background to normal
processing or, in conjunction with the special test packet, as part of their suite of system test functions. One
of the current problems with testing of DMX512 installations is that it must be done with static test packets –
the flicker finder modes of testers cannot be used while a console is actually running the show, as by
definition the DMX512 packets are varying as each cue runs. The interleaving of SIP’s would allow some
degree of live testing, particularly if one of more test packets were also sent applicable to the functionality of
the receiving device.
FPN: This scheme allows for a packet processing history to be traced back though a complex
installation of products.
7.13 SIP Checksum
7.14 Application
FPN: For systems requiring a more secure link, manufacturers would have the option of following every
normal packet with a SIP packet, although it is recognized that this would degrade data throughput. It
could be used with systems that send packets of fewer than 512 DMX512 slots or refresh data at less
than the maximum rate.
– 30 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
8 Receiver Performance
2
8.1 Loss of data tolerance / Resumption of acceptance of data
3
4
5
6
7
8
9
10
The receiving device must maintain, for a minimum of 1 Second, the last valid data value received for each
slot.
11
12
13
14
15
The performance of any device incorporating a DMX512 receiver must not be degraded by the presence at its
input of the continuous transmission of data packets containing any number of slot values up to the maximum
update rates specified in clause 5.
16
17
18
19
Unpowered connected DMX512 devices shall not degrade the performance of the DMX512 transmission
system.
20
21
22
23
Some products may provide their specified functionality without processing or being able to process every
consecutive DMX512 packet. Such products will have an inherent latency to data changes between packets,
which shall be declared by the manufacturer in accordance with the disclosure requirements of clause 12.
A receiver not receiving a Reset Sequence within one second of the previous Reset Sequence shall be
considered to have lost data input. Although this Standard does not specify loss of data handling procedures,
it does require that manufacturers state what their Loss of Data handling procedures are.
8.2 Receiver performance at maximum update rate
8.3 Inactive receiver input circuitry
8.4 Packet processing latency
– 31 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
9 DMX512 Systems Requiring DC Power
2
9.1 Accessory Power (24 VDC)
3
4
5
6
7
8
9
10
11
It is beyond the scope of this Standard to detail cable characteristics and system interconnection. This
Standard defines only signal levels, protection levels, connector style and pinouts and marking requirements.
12
9.2.1 Requirements for 12 VDC limited current power supplying devices
13
14
15
16
17
18
19
20
21
When a TYPE 5 DMX512 device provides limited current power, it shall provide this power on Pins 4 and 5 of
either the male or the female connector. Both Pins 4 and 5 shall be connected by less than 2 ohms to the
same positive voltage. This voltage is referenced to Pin 1.
A special cable scheme is generally required for use with these products which provides for high current
conductors on Pins 1 and 4 of the connector. In some situations it is advisable to daisy-chain products back to
the power source, effectively supplying power from both ends of the cable. Refer to manufacturers for other
details.
9.2 Limited current 12 VDC power for remote devices (TYPE 5 equipment)
If power is provided simultaneously on both male and female connectors, the manufacturer shall ensure that
the total current that can flow from any port is limited to 600 mA, even when the product is connected to other
TYPE 5 devices. One method of accomplishing this is diode isolating the connectors as shown in
figure 9.2.1. Loop-through connections are subject to the restrictions in clause 4.8.2.
Figure 9.2.1 - TYPE 5 Dual Sex Power Diode Isolation
22
23
24
25
26
27
28
29
30
The voltage shall be least +11.5 VDC and shall never exceed +12.5 VDC. The available current shall be
electronically limited to the range 300 mA - 600 mA, with the exception of battery powered devices which
shall be limited to the range 50 mA - 600 mA..
31
32
33
Devices designed to be powered by this supply shall function properly with input voltages in the range of
+8 VDC to +12.5 VDC and shall not consume more than 300 mA. Devices designed to be powered by this
supply shall not be damaged when powered by a voltage of +13 VDC.
Devices providing limited current power shall provide a means for disabling this power and for removing the
connection between Pins 4 and 5. Devices shall provide a clear indication whether or not the power is
enabled.
9.2.2 Requirements for devices designed to be powered by 12 VDC limited current
– 32 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
10 Connection Methods
2
10.1 Equipment fitted with external user accessible pluggable data link connections
3
4
5
6
7
8
9
10
11
This category includes all portable products.
12
13
14
15
16
17
Equipment in this category shall use 5 pin XLR connectors. The physical pinout of the 5 pin XLR shall be in
accordance with the Pin reference in this Standard as defined in table 2.8.2.2.
18
19
20
21
22
23
24
25
26
27
28
29
30
31
A concession to use an alternate connector is available only when it is physically impossible to mount a
5 pin XLR connector on the product. In such cases the following additional requirements shall be met :
1)
The alternate connector shall not be any type of XLR connector.
2)
The alternate connector shall not be any type of RJ45 connector except as allowed in
clause 11.5.
3)
Where marking is applied to any such alternate connector, it shall be marked as NCC
DMX512 (Not Connector Compatible), provided that all other requirements of this Standard
are met.
4)
The manufacturer shall provide an adapter cable with the appropriate connections to a
standard 5 pin XLR connector for all DMX512 ports included in the alternate connector.
5)
The TYPE and ground/isolation declarations shall continue to be declared for each port, and
shall be unambiguously associated with each 5 pin XLR adapter connection.
32
33
34
35
36
37
38
39
40
41
42
43
44
Products in this category may optionally use the 5 pin XLR connector, but shall not use any other XLR
connector. Where a non 5 pin XLR connector is used, this Standard makes no other restriction or stipulation
on connector choice. Manufacturers are encouraged to make adequate provision for cable restraint, loop in
and out of cables and provision of data link termination where necessary.
Female connectors shall be used on controllers and other transmitting devices and male connectors shall be
used on dimmers and other receiving devices. Female connectors shall also be used where loop-through
connections are provided.
Each DMX512 port shall be TYPEd in accordance with clauses 2.8 and 2.81.
10.1.1 Required Connector
Marking and identification of all ports shall be as required in clause 12.
10.1.2 Concession for use of an alternate connector (NCC DMX512)
10.2 Equipment intended for fixed installation with internal connections to the data link
When use is made of the 5 pin XLR connector, female connectors shall be used on controllers and other
transmitting devices and male connectors shall be used on dimmers and other receiving devices. Female
connectors shall also be used where loop-through connections are provided.
In all other cases, the connector sex is not specified.
Products in this category shall be TYPEd and marked in accordance with the provisions of clause 12.5.2.
– 33 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
10.3 Passive Data Outlets or Wall plate panels
2
3
4
5
6
7
8
Products in this category designed for temporary and generally accessible access to DMX512 data links shall
use 5 pin XLR connectors. Marking of such panels shall be in accordance with clause 12.5.3.
9
10
11
Panels which provide a data source on the primary data link shall use female connectors. Panels which are
intended to provide primary data link input signals back to another location shall use male connectors.
10.4 Products providing or requiring 24 VDC Accessory Power
Products in this category shall use a 4 pin XLR, with pinout in accordance with table 10.4.
Table 10.4 - Accessory Power Signal designations summary
12
Function
13
14
15
Data Link Common /
Supply Return
Primary Data Link
16
17
18
19
20
21
22
23
24
25
26
27
28
Accessory Supply
Pin Reference
within Standard
XLR
Pin
DMX512/2000AP
Approved
Abbreviation
1
1
Common (Screen)
COM
2
2
Data 1-
D1-
3
3
Data 1+
D1+
4
+24 VDC, Max 5 amps
24V
Female connectors shall be used on all sources of accessory power and male connectors shall be used on
receiving devices requiring power. Female connectors shall also be used where loop-through connections are
provided.
Manufacturers of accessory power sources shall be permitted to provide power output on a male connector,
in order to allow the use of looped cable systems, provided that there is termination of the primary data link
on Pins 2 and 3 of that male connector in accordance with clause 2.7 of this Standard.
Products in this category shall be marked in accordance with the provisions of clause 12.5.4.
10.5 Internal connections and specialized products for use with Category 5 cable schemes
29
30
31
32
33
34
35
36
37
38
39
40
41
42
Limited use of Category 5 cable schemes is permitted in accordance with clause 11.5 of this Standard.
The use of RJ45 connectors (plugs/jacks) and punchdown terminal blocks shall be limited to connections
which are part of a fixed installation and not normally accessible or intended for regular connection and
disconnection.
43
44
45
Systems using this auxiliary power shall be cabled so that the voltage drop in the return conductor (shield) of
the control cable shall be limited to 2.5 VDC. Systems shall also be cabled so that the available supply
voltage to the device shall be +8 VDC or higher.
RJ45 connectors (plugs/jacks) are permitted only on patch and data distribution products and only when
installed in controlled access areas.
Any use of RJ45 connectors or punchdown terminal blocks shall use the wire color and cable pair reference
in accordance with table 11.5.
Products in this category shall be TYPEd and marked in accordance with the provisions of clause 12.5.5.
10.6 Special provisions for TYPE 5 equipment
– 34 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
11 Cable
2
11.1 Background
3
4
5
6
7
8
9
10
The high data transmission rate (250Kbaud) used by DMX512 requires the selection of a cable which does
not significantly distort the signal or give rise to spurious signal reflections. Cables intended for use with
audio systems (microphone cables), while having the convenience of flexibility, availability and relative low
cost, are NOT suitable for use with DMX512 because of their high capacitance and incorrect characteristic
impedance; at DMX512 data rates this will give rise to bit time distortion and signal reflections/overshoot,
particularly over long (> 10m) distances.
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
Cabling systems shall provide a balanced, nominal 120 ohm terminated transmission system, and be made
of cables with a characteristic impedance in the range 100-150 ohm.
26
27
28
29
30
31
Cable for general application shall be shielded twisted pair approved by its manufacturer for EIA-422/EIA-485
use at high data transmission rates and distances of at least 500 meters. Conductors in cable for portable
equipment shall be of stranded construction.
32
33
34
35
36
37
Any cable satisfying the requirements of clauses 11.2 and 11.3 may be used for connections between items
of fixed equipment, subject to local regulatory requirements regarding voltage and insulation styles.
11.2 General
FPN: Note that mixing cables of different impedances and other characteristics not isolated by buffers
or other processing devices may affect system reliability.
Installations using cables with one pair are referred to as Cable Scheme C1 in this Standard. The use of
Cable Scheme C1 limits systems to the basic functionality offered by TYPE 0 ports. Other types of product
may be interconnected but operation will be limited to transfer of data on the primary data link.
Installations using cables with two pairs are referred to as Cable Scheme C2 in this Standard. The use of
Cable Scheme C2 is required for the interconnection of products with TYPE 1, TYPE 2, TYPE 3, TYPE 4 or
TYPE 5 ports.
11.3 General Applications and between all Portable Equipment
11.4 Cable between permanently installed fixed equipment
The use of Category 5 cable shall be permitted and shall follow the specific installation and termination
requirements of clauses 11.5.
– 35 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
2
3
4
5
6
7
8
9
10
11
12
13
14
11.5 Specific Requirements relating to the use of Category 5 cable
Installations using Category 5 cable implementing the one pair functionality of Cable Scheme C1 are referred
to as Cable Scheme C5.1. This configuration limits systems to the basic functionality offered by TYPE 0
ports, but does permit two universes to be carried on one cable.
Installations using Category 5 cable implementing the two pair functionality of Cable Scheme C2 are referred
to as Cable Scheme C5.2. The use of Cable Scheme C2 is required for the interconnection of products with
TYPE 1, TYPE 2, TYPE 3, TYPE 4 or TYPE 5 ports., and is the preferred implementation.
Table 11.5 Connection Schedule for DMX512 systems using Category 5 Cable
Pair
Color
Function
Cable Scheme C5.1
Cable Scheme C5.2
1
white / orange
data A +
DMX512 Pin 3
DMX512 Pin 3
2
orange
data A -
DMX512 Pin 2
DMX512 Pin 2
3
white / green
data B+
DMX512 b Pin 3
DMX512 Pin 5
6
green
data B -
DMX512 b Pin 2
DMX512 Pin 4
4
blue
v not exceeding - 0 / + 25 VDC
5
white / blue
0 v (signal common) | Wire 4
common
DMX512 Pin 1
DMX512 Pin 1
7
white / brown
v not exceeding - 0 / + 25 VDC
8
brown
0 v (signal common) | Wire 7
common
DMX512 b Pin 1
Wire 7 common
Pair 2
Pair 3
Pair 1
15
Pair 4
16
Shield
17
18
19
20
21
22
23
24
25
26
27
28
Wire #
drain
Note: Category 5 cable wire pair numbering and color in accordance with TIA T568B.
Warning: Accidental connection of legacy or TYPE 5 equipment to non-DMX512 equipment likely to be
encountered (e.g., an Ethernet Hub at a patch bay) may result in damage to equipment.
Warning: Wires 4 and 7 are reserved for general power use by manufacturers whose distributed DMX512
buffering products require low voltage DC power. As this voltage is never connected to an end user XLR
connector, it should not be confused with TYPE 5 limited current power arrangements, nor is it Accessory
Power as it is not accessible to the end user. Such systems are currently beyond the scope of this Standard.
11.5.1 Shielded (Foiled) Twisted Pair Category 5 cable (STP/FTP)
29
30
31
32
Earth grounding of the Shield shall be in accordance with arrangements detailed in figures 11.5.4.1 and
11.5.4.2.
33
34
UTP shall only be installed in earth grounded metal conduit.
11.5.2 Unshielded Twisted Pair Category 5 cable (UTP)
– 36 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
11.5.3 Category 5 cable termination requirements
2
3
4
5
Product intended for use with Category 5 Cable such as receptacle plates or hard-wired signal processors,
shall be suitable for termination of both UTP or STP/FTP Cable.
6
7
8
Figures 11.5.4.1 and 11.5.4.2.1illustrate conversion from XLR Connector and EIA-485 cable to Category 5
cable with a Punchdown block and back, along with required grounding practices.
11.5.4 Category 5 grounding practices
Figure 11.5.4.1 - Scheme C5.2 with (1) Universe in a TYPE 1 - 5 Implementation
9
Figure 11.5.4.2 - Scheme C5.1 with (2) universes & (2) TYPE 0 Implementations
10
– 37 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
11.5.5 Category 5 grounding practices with UTP and STP/FTP cable
2
3
4
Figure 11.5.5 illustrates conversion from Shielded Category 5 cable to Unshielded and back and required
grounding practices.
Figure 11.5.5 - Mixed UTP & STP / FTP Installation
5
6
7
8
9
10
11
12
13
Note: Use of buffers or other means to mitigate different impedances of the different cable types is not
addressed in this figure.
11.6 Cable application rules
Table 11.6 summarizes the various constructions of cable suitable for use with DMX512 and how they can be
implemented.
Table 11.6 - Cable application rules
Type
14
15
16
Use
17
18
19
20
21
22
23
Solid Conductors
Stranded Conductors
EIA-485
UTP
Category 5
STP/FTP
Category 5
Portable
No
No
No
Permanent
OK
In Earthed
Metal Conduit
Only
OK
- Note 2 -
UTP
Category 5
STP/FTP
Category 5
OK
- Note 1 -
No
OK
- Note 1 -
OK
- Note 2 -
In Earthed
Metal Conduit
Only
OK
- Note 2 -
EIA-485
Note 1: It is recommended that braided shield be used for better durability
Note 2: Use of Plenum Rated cable without conduit allowed
– 38 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
12 Marking and Disclosures
2
12.1 Identification
3
4
5
6
7
8
9
10
11
12
13
14
15
Only equipment conforming to this Standard may be marked and identified with "USITT DMX512/2000" or
"DMX512/2000".
16
17
18
19
20
21
22
23
24
25
26
Where required by clauses 12.3 through 12.5, all ports shall be marked as to the applicable TYPE as defined
in table 2.8.2.1.
Only receivers also capable of accepting a 4 microsecond MARK AFTER BREAK may be marked and
identified as "USITT DMX512/2000 (4µSec)" or "DMX512/2000 (4µSec)".
FPN: The original version of this Standard (1986) allowed transmit packets with a 4 microsecond
Mark After Break. This minimum was revised to 8 microseconds in the 1990 edition.
All marking shall comply with the style sheet requirements shown in Annex D – Port Marking Style Sheet. All
information provided by marking shall also be provided in the equipment manual.
12.2 TYPE and Pin marking
Where declaration of pinout detail is required by clauses 12.3 through 12.5, manufacturers shall use the
signal designations from table 2.8.2.2 in any marking of pin, contact or terminal functions appearing on or
within a product and associated with installation or connection. Such details are dependent on the declared
TYPE of the port.
Where it is necessary to use abbreviations, only those detailed in table 12.2 shall be permitted.
Table 12.2 - Signal designations abbreviations allowed for marking
27
Function
Abbreviation
28
Common (Screen)
COM
29
Primary Data Link – Data 1-
D1-
30
Primary Data Link – Data 1+
D1+
31
Secondary Data Link – Data 2-
D2-
32
Secondary Data Link – Data 2+
D2+
33
Secondary Data Link – Talkback-
TB-
34
Secondary Data Link – Talkback+
TB+
35
12 VDC
12V
36
24 VDC Accessory Power
24V or AP
37
– 39 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
12.3 Ground / Isolation marking
2
3
4
5
All DMX512 ports shall also be marked as to the relationship between Pin 1 and earth ground. The allowed
grounding topologies are shown in table 12.3.
Table 12.3 Ground / Isolation marking
6
Function of Port
Defining Figure
Comment
Approved
Marking
7
Transmitter
fig 3.3.1
Ground Referenced
no mark required
8
Transmitter
fig 3.3.2
Isolated
ISOLATED
9
10
11
Transmitter as part of
buffer or processing
device
fig 3.6.1
Floating
FLOATING
12
13
14
Transmitter as part of
DMX512 source with
non-DMX512 inputs
fig 3.6.2
Ground Referenced
no mark required
15
Receiver
fig 3.5.1.1 or 3.5.1.2
Non-isolated,
100 ohm 2 Watt resistor
no mark required
16
Receiver
fig 3.5.1.1 or 3.5.1.2
Non-isolated with
concession per note 3 of
the figures
17
18
Receiver as part of a
processing device
fig 3.6.3
Grounded
19
Receiver
fig 3.5.2
Isolated
ISOLATED
20
21
22
Receiver as part of a
buffer or processing
device
fig 3.6.1
Floating
FLOATING
23
24
12.4 Data line termination marking
25
26
27
28
29
The marking for DMX512 input ports that are permanently terminated shall include the word ‘TERM’. Marking
for DMX512 input ports with switched termination shall not include the word ‘TERM’. The means controlling
the termination shall be identified in an appropriate manner.
30
12.5.1 Portable products and products fitted with external pluggable data link connectors
31
32
33
34
35
36
37
38
39
40
Ports on these products shall be TYPE marked in accordance with clause 12.2.
12.5 Required disclosures
Ports on these products shall provide Ground/Isolation marking in accordance with clause 12.3.
Connector pinout detail on all TYPE 5 ports shall be provided in accordance with clause 12.2. The declaration
of pinout detail for other TYPEs remains optional.
If use has been made on any non XLR connector in conjunction with the supply of an adapter cable, the
non-XLR connector shall be also be marked as NCC DMX512/2000.
– 40 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
12.5.2 Equipment intended for fixed installation with internal connections to the data link
2
3
4
5
6
7
8
9
Ports on these products shall be TYPE marked in accordance with clause 12.2.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Ports on these products shall provide Ground/Isolation marking in accordance with clause 12.3.
Clearly identified connector pinout detail shall be marked on or within any product in accordance with
clause 12.2.
12.5.3 Data outlet or wall plates fitted with 5 pin XLR connectors
Where a 5 pin XLR female or male connector is fitted to a wall plate or facility panel in a manner that links it
directly back to a patch panel or data distribution buffer, its TYPE cannot be determined without reference to
the product to which it is ultimately patched and the cable scheme implemented.
Manufacturers and Installers of such data outlets shall be permitted to mark the XLR connectors in
accordance with table 12.5.3. If the site cable scheme or pinout does not follow this table, no reference to
DMX512, including use of the term “DMX”, shall be permitted.
No reference to DMX512/2000 shall be permitted.
FPN: the “/2000" indicates electrical characteristics of active electronics compliant with this edition of
the Standard, which are not known at the passive wall plate.
Table 12.5.3 - 5 pin XLR data outlet / wall plate marking
25
26
5 Pin XLR Pins Wired
27
1, 2, 3
C1
DMX512 Scheme C1
28
1, 2, 3
C2
DMX512 Scheme C1
29
1, 2, 3, 4, 5
C1
not permitted
-Note 1-
30
1, 2, 3, 4, 5
C2
DMX512 Scheme C2
necessary for use with
TYPE 2 – TYPE 5 ports
31
a(1, 2, 3) b(1, 2, 3)
C5.1
DMX512 Scheme C1
One CAT 5 Cable w/ two universes
32
1, 2, 3
C5.2
DMX512 Scheme C1
Can be upgraded to full wiring of
XLR and remarked for Scheme C2
at later date if required
33
1, 2, 3, 4, 5
C5.2
DMX512 Scheme C2
necessary for use with
TYPE 1 – TYPE 5 ports
34
35
36
37
Cable Scheme
Permitted Marking at
XLR
Comments
Can be upgraded to full wiring of
XLR and remarked for Scheme C2
at later date if required
Note 1 : this is inconsistent with designated cable scheme.
– 41 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
12.5.4 Products providing or requiring 24 VDC Accessory Power
2
3
4
5
6
7
8
9
10
11
12
Accessory power equipment claiming compliance and using the designated 4 pin connector may be marked
as DMX512/2000AP (AP for Accessory Power).
13
14
15
16
17
18
Ports on these products shall be TYPE marked in accordance with clause 12.2.
Ports on these products shall provide Ground/Isolation marking in accordance with clause 12.3.
19
12.5.6.1 Required disclosure for TYPE 5 devices
20
21
22
23
24
25
26
27
28
29
The current capacity for supplying devices and the current requirements for consuming devices shall be
provided in the device manual. The manual must state that using remotely powered devices may disable
other DMX512 features and may cause damage to non-compliant DMX512 legacy equipment.
30
31
32
33
34
35
36
Manufacturers of devices intended to be remotely powered shall provide clear instructions to allow a user to
construct systems that meet all cable voltage drop requirements. An example of such instructions would be
to specify the length of a particular gauge cable that may be used between the power supplying device and
the power consuming device. If a particular kind of cable is specified, that cable type shall be readily
available.
37
38
39
40
41
This Standard does not define loss of data handling procedures (clause 8.1) beyond requiring that
manufacturers declare their own products’ procedure(s). Such declarations shall be made in the equipment
manual.
42
43
44
45
46
Manufacturers shall declare any inherent latency to data changes between packets in the equipment manual.
This may be in terms of response time or other wording as chosen by the manufacturer, but shall clearly
indicate if the product design might legitimately ignore some packets in normal operation.
Pinout details shall appear on the product in accordance with either the DMX512/2000AP or approved
abbreviation columns of table 10.4.
No reference to TYPE is permitted.
Ports on these products shall provide Ground / Isolation marking in accordance with clause 12.3
12.5.5 Internal connections and specialized products for use with Category 5 cable schemes
Ports on these products may marked as NCC DMX512/2000.
12.5.6 Equipment with Type 5 ports - additional disclosures
The manual shall declare the method used to limit current on loop-through ports as required by clause 4.8.2.
The manual shall clearly describe how to disable the remote powering. It shall describe any changes needed
to make the device coexist with other DMX512 devices that require the use of Pins 4 and 5 for data.
12.5.6.2 Cable information requirements for TYPE 5 equipment
12.5.7 Loss of data handling procedure
12.5.8 Packet Processing latency
– 42 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
12.5.9 NULL START Code functionality
2
3
4
5
6
7
8
9
Manufacturers of transmitting devices shall declare in the device manual the full range of slot values
transmitted in conjunction with packets sent using the NULL START Code.
Manufacturers of receiving devices shall declare the response to packets received containing the NULL
START Code, with particular reference to any functionality requiring limited or restricted slot data values, in
the equipment manual.
12.5.10 Slot footprint
10
11
12
Manufacturers of receiving devices shall declare the slot footprint in the equipment manual.
13
14
15
16
17
18
Manufacturers claiming compliance with this Standard shall include the table and text of Annex C in their
product documentation. Manufacturers of TYPE 0 through TYPE 5 equipment shall shade or otherwise
indicate the column and row that apply to their product. Manufacturers of cable and passive cabling systems
are not covered by this requirement.
19
20
21
22
23
24
25
26
27
28
29
Manufacturers claiming compliance with this Standard shall complete and hold on file a Protocol
Implementation Compliance Statement (PICS) as defined in Annex E. Copies of the PICS shall be made
available on request.
12.5.11 Device interconnection
12.6 Compliance
= END =
– 43 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
7KLV 3DJH $OPRVW %ODQN
– 44 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
be published in part or in whole or be duplicated for-profit or sold in any manner.
It may not
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
2
3
ANNEX A (Normative) - Alternate START Codes Registration & Reserved Codes
A1 Alternate START Code Registration Policy: 1 - 255 decimal (01 - FF hexadecimal).
4
5
6
7
8
9
10
The first frame of a DMX512 packet is the START Code. The value of this frame identifies intended use of
data in the rest of the packet. The Standard provides for a non NULL or “Alternate” START Code. Where it
is required to send proprietary information over a DMX512 data link, a packet starting with a registered
Alternate START Code shall be used.
11
A2.1 Authorized use
12
13
14
15
The E1 Accredited Standards Committee or any organization that it authorizes may use an Alternate START
Code to provide further extensions to the DMX512 Standard.
16
17
18
19
20
21
Alternate START Codes from 92 to CE hexadecimal shall be reserved for possible future revisions of this
Standard. No equipment shall be manufactured that generates any of these codes until their use is defined
by the Standard. 90h is reserved for future expansion. 91h followed by a 2 byte Manufacturer ID field is
reserved for Manufacturer/Organization specific use.
22
23
24
25
26
Alternate START Code 55 hexadecimal is reserved for a special Test Packet, Alternate START Code
17 hexadecimal is reserved for a Text Packet, and Alternate START Code CF hexadecimal is reserved for a
System Information Packet. See clauses 6.6, 6.7, and 7 for descriptions.
27
28
29
30
31
32
33
34
Alternate START Codes F0 - F7 shall be reserved for prototyping/experimental use while the
manufacturer/organization is waiting for their registered Alternate START Code to be assigned. Any
manufacturer/organization can use any of these during the development process without risking conflict with
production equipment during field tests. Manufacturers shall not advertise or sell products or devices that use
Alternate START Codes F0 - F7.
35
36
37
38
39
40
41
Any manufacturer or organizations involved in the use of DMX512 may request that a START Code or
Manufacturer ID be registered for their use. Requests shall be forwarded to the Secretariat for the E1
Accredited Standards Committee – ESTA. ESTA will attempt to honor such reasonable requests as
described below.
42
43
44
45
No more than one Alternate START Code may be registered to any one manufacturer/organization.
Manufacturers and Organizations with Alternate START Codes registered prior to the publication of this
edition of this Standard may request one additional Alternate START Code this issue of the Standard.
A2 Alternate START Codes Reserved
A2.2 Future revisions
A2.3 Test, Text, and System information packets
A2.4 Alternate START Codes reserved for development
A3 Requests For Registration of New START Codes and Manufacturer IDs
A4 Number of Alternate START Codes per entity
– 45 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
A5 Selection of the Alternate START Code value and Manufacturer ID
2
3
4
5
6
7
The assignment of any particular numeric START Code or Manufacturer ID value to any particular entity is
solely up to the E1 Accredited Standards Committee. Assignment depends on the availability of unused and
unreserved START Codes and Manufacturer IDs.
8
A6.1 Documentation for use of Alternate START Codes
A6 Documentation Register
9
10
11
12
13
14
15
16
The manufacturer/organization requesting registration of an Alternate START Code shall provide a 2-line
description of the purpose of the Alternate START Code. They shall list the minimum and maximum number
of frames, including the START Code, in any proposed packet. Any provided description (subject to editing)
shall be included in the Register. This is not required for functions associated with a manufacturer specific ID
under Alternate START Code 91. It is recommended, but not required, for Alternate START Codes assigned
prior to the adoption of this version of the Standard.
17
18
19
20
21
22
The E1 Accredited Standards Committee through its secretariat (ESTA) shall maintain a Register of Alternate
START Codes and Manufacturer IDs. ESTA will publish the Registry on a regular basis, not less than once
per year, and will provide updates in its publications as they occur.
23
24
25
26
27
If the manufacturer/organization wishes detailed documentation to be in the Public Domain, a note will be
added to the Registry, but they will be responsible for such publication.
28
29
30
31
32
33
34
35
The DMX512 Standard is copyrighted. By registering a START Code or Manufacturer ID, no ownership rights
are conferred to any third party. Alternate START Codes are registered to particular entities solely to allow for
orderly management of the Standard. The registrant does not own the Alternate START Code.
A6.2 Maintenance and Publication
A7 Supplemental documentation
A8 Ownership
-end of Annex A-
– 46 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
2
3
4
5
6
7
8
9
10
11
12
13
Annex B (Normative) - Type 3 DMX512
14
15
16
17
18
19
20
21
22
23
24
25
This document describes the communications protocol originally implemented as an extension to USITT
DMX512/1990 by ROSCO/Entertainment Technology's Intelligent Power System (IPS) dimmers to return data
from the dimmers to the console, a separate status monitor, or other device. This protocol, originally known
as the Intelligent Diagnostic Specification (IDS), is a strict superset of E1.11 (DMX512/2000).
26
B1.1 General
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
The advantage of the talkback scheme described herein is its simplicity, adaptability to a variety of DMX512
devices, response speed, and automatic response to any standard DMX512 data stream. The adoption of
this protocol as TYPE 3 DMX512 avoids incompatible use of the DMX512 spare pair and saves
manufacturers and end users from the problems of integrating incompatible systems.
Preface (not part of the Standard)
Until adoption of this Standard, all designs, constructions and other disclosures set forth herein are the
property of ROSCO/Entertainment Technology and such information is imparted to you in confidence. In
accepting this information you agree not to reproduce it, to disclose it, or to have it manufactured in whole or
part without our written permission. This information is not in the public domain. ROSCO/Entertainment
Technology retains full copyright protection. It is made available as a "royalty-free license" to parties who
have signed an agreement of compliance. Upon adoption of this Standard, ROSCO/Entertainment
Technology will either transfer the copyright to USITT and ANSI ASC E1 (ESTA) for administration or make
other appropriate arrangements to ensure that this is not an obstacle to publication.
Annex B Foreword
Rights are granted only to the data return technique described herein. This agreement grants no rights of any
kind to ROSCO/Entertainment Technology's patented IPS power control technology, which are covered in
whole or in part by one or more of the following U.S. patents: 5,004,969 and 5,239,255. Other Patents
Pending, foreign and domestic.
B1 Introduction
This document defines an extension to the DMX512 Standard to allow data to be returned from lighting
equipment and accessories by making use of the two "optional" data lines on the standard cable, defined in
the Standard as "second data link" and located on DMX512 port Pins 4 and 5. The TYPE 3 specification in
no way prevents a manufacturer from incorporating a proprietary "query-and-response" protocol using
alternate DMX512 START Codes into a product. The TYPE 3 DMX512 talkback specification simply allows
for both a simple universal and a vendor-specific data return format to peacefully coexist on Pins 4 and 5 of a
DMX512 port.
This annex is organized into three major sections - an overview of the return data extension to the DMX512
Standard, a summary of the original data return format as implemented by ROSCO/Entertainment
Technology, and an example detailing the data returned by ROSCO/Entertainment Technology’s IPS
products.
– 47 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
B1.2 Compliance
2
3
4
5
6
Manufacturers implementing TYPE 3 DMX512 shall support as a minimum, identification of manufacturer
device type and on-line/off-line status in their talkback monitoring system. It is hoped that vendors will
support as much data as possible.
B1.3 Definitions
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
A system implementing this protocol extension consists of three types of devices connected to the DMX512
data link:
23
B2.1 Synchronizing the return data
24
25
26
27
28
29
To permit operation with existing DMX512 transmitters, the returned data must be synchronized with the
outbound control data on at the DMX512 port Pins 2 and 3 (see Figure B2.1 below). Ideally, each responder
would supply one byte of response data precisely synchronized to the level byte that was transmitted to it in
the control stream. However, propagation delays in any real-world distributed DMX512 installation would
prohibit precise synchronization and data "collisions" would result.
B1.3.1 Transmitter: generates the standard-conforming stream of DMX512 control packets. This function is
generally performed by the console. There can be at most one active transmitter on a DMX512 data
link.
B1.3.2 Responder: is a dimmer or other DMX512-compatible device which generates responses in reaction
to packets from the transmitter. There can be many (up to 171) responders on a data link.
B1.3.3 Monitor: is a device which receives and interprets the data returned by the responders. This function
may be performed by a stand-alone device (e.g., the IPS Status Monitor) or may be combined with
the transmitter function in a console. A system can have zero, one, or many monitors.
B2 TYPE 3 Protocol
Figure B2.1 - Synchronization of Return Data to Control Stream
30
31
32
33
To guarantee that independent, distributed DMX512 devices can reliably return data without collisions, the
return data protocol requires that only one byte of data be returned for every three slots in each DMX512
packet. The 512 possible DMX512 addresses are divided into 171 possible groups, with group 1 comprising
– 48 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
slots 1, 2, and 3; group 2 of slots 4, 5, and 6, and so on. In general, group i consists of slots 3i-2, 3i-1, and 3i.
Note that, if the number of slots transmitted is not an exact multiple of 3, the last group will consist of one or
two slots. (See Figure B2.1 above, for the example of group 171.)
22
23
24
25
26
27
28
29
30
Response frames are 11-bit characters, sent at a 250 Kbps data rate. Response frames comprise one start
bit, eight data bits, one flag bit and one stop bit. The flag bit is set to one only on RESPONSE START ID bytes.
This allows the monitor to find the beginning of a response sequence and resynchronize.
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
Due to the synchronization described above, a monitor must observe both the data from the transmitter and
the data returned from the responders to be able to correctly interpret which group of slots should be
associated with a response byte. The monitor must also maintain a separate state for each of the 171
possible groups, as each responder can operate asynchronously and be at a different point in its return data
sequence from other responders on the same link.
The protocol, therefore, requires that one responder answer for each group of three slots that wish to return
data. That responder is responsible for transmitting one byte of return data per DMX512 packet that
addresses it. The responder shall transmit its data on receipt of the first slot in its associated group. The
start bit of the response frame shall start no earlier than the rising edge of the DMX512 slot stop bit #1 and no
later than 40 microseconds after that rising edge.
Each responder transmits a repeating sequence of bytes, the format of which is indicated by the RESPONSE
START ID byte which flags the beginning of the sequence. In general, the RESPONSE START ID is followed by
zero or more bytes of data common to all three slots in the group, followed by zero or more bytes of data per
slot. Once all bytes in the sequence have been sent, a new sequence commences with a new RESPONSE
START ID. It is obvious that the update rate of the talkback data is directly proportional to the update rate of the
transmitted DMX512 data.
FPN: For example, at a 44Hz DMX512 update rate, returning 26 bytes of data for all 171 response
groups takes 1.7 seconds
B2.2 Response frame format
A maximum sequence of 32 bytes, including the RESPONSE START ID byte, are permitted per group.
(Ed. Note: ROSCO/Entertainment Technology is currently maintaining the list of RESPONSE START ID byte assignments).
B2.3 Monitor implementation issues
The monitor should read the captured response data after the rising edge of the stop bit of the third data slot
of each group. The capture shall happen no later than 40 microseconds from that rising edge. If no
character is received during the transmission of the three slots comprising the group, the monitor should
assume that the return data stream for that group has been interrupted, and ignore any subsequent
characters until another RESPONSE START ID is received.
After startup, or after any serious error condition, the monitor should ignore all response data from each group
until a RESPONSE START ID byte (i.e., a byte with a flag bit = 1) is seen. If the RESPONSE START ID byte is not
one that the monitor recognizes, it should again ignore data until a valid one is seen for the group in question,
as a responder may chose to interleave sequences with different formats.
– 49 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
B3 Hardware Implementation Issues
2
B3.1 Introduction
3
4
5
6
7
The hardware required to implement talkback is straightforward. The return data channel is EIA-485 and
shall comply with all other provisions of this Standard, including clauses 2 through 4. Each responder drives
the line in response in coming data according to the format described in Figure B2.1.
8
9
10
11
12
13
14
15
Each responder shall have an EIA-485 line driver with a driver enable control. The driver enable control
should be connected to the responder UART's RTS (Request-to-Send) pin through logic that will enable the
driver when RTS is asserted by the UART. This will automatically gate the driver on and off at the proper
time. If the UART does not have RTS control, responder software must control the line driver and gate it on
and off the line at the proper time. In general, the line driver should be enabled one bit time prior to
transmission, and disabled one bit time after the last bit has been sent.
16
17
18
19
20
The UART should support 9-bit mode since RESPONSE START ID bytes use this bit as a flag. Many
microcontrollers and UARTs directly incorporate this mode. Others emulate it by allowing the 9th bit (which is
the parity bit position) to be directly set or cleared.
21
22
23
24
25
26
27
28
29
30
The return data line must be terminated at both ends with a 120 ohm termination. This termination must also
be "fail-safed" at the return data receiver to hold the line in the MARK state when none of the responders is
driving the line. The termination at the bidirectional distribution amp receiver is always active since this point
is always the end of a particular DMX512 link. It is critical that receiver inputs be properly
terminated/failsafed at all times.
B3.2 Line Driver
B3.3 UART
B3.4 Line Termination
The overall termination resistance value must result in a value equal to the characteristic impedance of the
line. The EIA-485 specification calls for a 120 ohm termination resistor at each end of the line. Therefore,
the termination value must be 120 ohms. A basic schematic of the circuit is shown in Figure B3.4.
Figure B3.4 - External Line Termination
31
32
33
The effect of the pull-up and pull-down resistors, R1, are that they will appear to be summed together in
parallel with the termination resistor R2.
– 50 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
2
3
4
5
6
7
8
9
10
11
12
13
Reducing R1 will increase the threshold voltage, increasing the noise immunity when the line is high
impedance. It is desirable to have at least 250mV of threshold voltage when both ends of the line are
terminated. The EIA-485 specification requires a 200 mV maximum threshold for a receiver, so 250mV
provides a 20% margin. Since the link will be terminated at each end, the threshold set for each termination
must be twice the desired threshold of the fully-terminated case.
14
15
16
17
18
19
20
21
22
23
The return data standard requires bi-directional distribution/return data combiners. The DMX512 output data
may be split and separately buffered as in standard DMX512 buffers. Return data receivers must be "wireOR" connected within a unit. This combined received data signal is used to drive back to the return data
monitor. Distribution amplifier talkback outputs are active at all times.
A threshold of 500mV is selected, since it will decrease to 250mV when both ends of the cable are
terminated. Because it is desirable to use standard resistors, R2 is increased to 133 ohms, the nearest
standard 1% value. It is also desirable to make R1 part of a resistor package, which will ensure close
tolerance and matching. The nearest standard value which will give the desired threshold voltage is
560 ohms. The actual noise margin is 0.530V, and the impedance is 118.9 ohms.
B3.5 Bi-directional distribution amplifiers
Optoisolation should be provided between the EIA-485 circuits. Power for each link may be provided by
separate transformers and voltage regulators, or by isolated DC-to-DC convertors. The bidirectional
distribution amplifier should not perform any processing on the data, since the talkback protocol depends
upon the relationship with outbound DMX512 to synchronize the return data.
Isolated DMX Link # 1
*
DMX input
*
Isolated DMX Link # 2
"Wire -OR"
*
Talkback output
*
* Opto-isolator
To additional isolated links within unit
Figure B3.5.1 - Bi-directional TYPE 3 DMX512
Distribution Amplifier
24
25
26
27
28
29
Multiple units may be cascaded to provided a large number of separate DMX512 links. No DMX512
responders can be present on the DMX512 links between distribution amplifiers or between the status
monitoring device, shown in Figure B3.5.2 as dashed lines. This is because the return data lines on this links
are always driven by the distribution amplifiers.
– 51 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
Responder
DMX Lighting
Console
Responder
DMX
Processor
To responders
Responder
Responder
Status
Monitor
Responders OK
No responders
Figure B3.5.2 - Cascaded bidirectional distribution amplifiers
1
2
3
4
5
6
7
8
9
10
11
12
13
14
Figure B3.5.2 shows the proper usage of distribution amplifiers and proper placement of responders. If a
DMX512 processor unit (i.e., a DMX512 combiner or backup unit) is installed, it is considered to be the
source of the DMX512 data stream. If the console in Figure B3.5.2 supported talkback, it would not work
because of the DMX512 processor, which would be generating a new data stream. The status monitor would
work correctly since it is "downstream" of the DMX512 processor.
B4 Basic Dimmer Status Data Format
This clause is a summary of the data return format as implemented by ROSCO/Entertainment Technology. It
may also be used a guideline for developing a specific format for any type of DMX512 device.
ROSCO/Entertainment Technology IPS dimmer strip and dimmer box products use RESPONSE START ID = 0,
indicating that a 26-byte sequence follows the start id, in the following format:
– 52 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
+0
+1
RESPONSE
START ID
+2
FIRMWARE
VERSION
CONFIGURATION
Headend Data
+3
STATUS
FLAGS
+4
ERROR
FLAGS
+5
CONFIGURATION
+6
DETAIL
FLAGS
+7
+8
+9
TEMPERATURE
LOAD SIZE
PRESENT
LEVEL
+15
+16
+17
+10
LINE
VOLT.
Dimmer # 1 Data
+11
STATUS
FLAGS
+12
ERROR
FLAGS
+13
CONFIGURATION
+14
DETAIL
FLAGS
TEMPERATURE
LOAD SIZE
PRESENT
LEVEL
+18
LINE VOLT.
Dimmer # 2 Data
+19
STATUS
FLAGS
+20
ERROR
FLAGS
+21
CONFIGURATION
+22
DETAIL
FLAGS
+23
TEMPERATURE
+24
LOAD SIZE
+25
PRESENT
LEVEL
+26
LINE VOLT.
Dimmer # 3 Data
Figure B4 - IPS Return Data Stream Format
1
2
3
4
5
6
The sequence starts with two bytes describing data common to all three dimmers in the group, followed by
eight bytes specific to each dimmer, in the order dimmer 1, dimmer 2, dimmer 3. The detailed format of each
byte is noted in the following sections.
7
B5.1 Headend Firmware Version
8
9
10
B5 Example return data format detail
This byte allows the console or status monitor to determine what release of the operating firmware is present
in the addresses bar/box. The response is formatted as follows:
11
BIT(S)
SIGNIFY
EXPLANATION
12
7-4
MAJOR
The major release level of the head-end firmware, coded as a BCD digit.
13
3-0
MINOR
The sub-level within a major release, as a BCD digit.
14
15
– 53 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
B5.2 Headend Configuration
2
3
The headend CONFIGURATION BYTE conveys information common to all dimmers in the present group, in the
following format:
4
BIT(S)
SIGNIFY
5
7
ERROR AT POWER UP
6
6
PREHEAT
7
5-4
FULL OUTPUT
EXPLANATION
If set, the headend detected a significant error during its power-up
diagnostics. The specific error encountered can be determined by
observing the display on the headend of the bar/box during power-up.
If set, preheat is enabled for the bar/box. If clear, preheat is disabled for
the bar/box.
Show the voltage to be provided as full output (i.e., level value = 255)
according to the following table:
Value of
Full Voltage If
Full Voltage If
FULL OUTPUT
240 VOLT = 0
240 VOLT = 1
00
120
240
01
115
230
10
110
220
11
100
200
In addition, if FULL OUTPUT = 11, a modified square law dimmer curve
(customized for the 100V environment) is substituted for the standard
square law curve.
8
3
DIMMERS 4-6
9
2
ANALOG OPTION
ABSENT
10
1
SIX DIMMER
11
0
120 VOLT
If set, this data stream is from the second group of three dimmers in a
six-dimmer bar or box (see SIX DIMMER, below). If reset, the data stream
is from the first group of dimmers. This bit, when used with SIX DIMMER,
allows a monitor to correctly determine the base address of the bar/box
associated with a data stream.
If set, the headend does not have AMX192 or 0-10V analog control
capabilities. If reset, an analog option is present.
If set, the bar/box contains six dimmers; if reset, the bar/box is
configured for three dimmers.
If set, the bar/box is configured for 100/120V operation; if reset, the
bar/box is configured for 220/230/240V operation.
12
13
– 54 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
B5.3 Dimmer Status
2
3
4
The dimmer status byte summarizes the dimmer's operating status, including an indication if any serious errors are
present, in the following format:
5
BIT(S)
SIGNIFY
6
7
NO RESPONSE
Set if the dimmer did not respond to the last command and may be
absent or non-functional.
7
6
NON-DIM
Indicates that the dimmer is now running as a non-dim if set; if clear
indicates normal operation.
8
5
9
4
LOCAL MODE
10
3
NO LOAD
11
2
INDUCTIVE LOAD
Set if the load or source has been determined to be inductive, and the
dimmer is operating in Forward Phase Control mode as a result.
(Additional information on how the inductive load was sensed is
supplied by the FPC CAUSE bit in the DIMMER DETAIL byte.)
12
1
REDUCED RISE/FALL
Set if the dimmer is using short (250 µS) rise and falltimes due to high
power device temperature.
13
14
15
0
ERROR PRESENT
EXPLANATION
VARIABLE FREQUENCY Set if the line frequency has been outside the range 59.5-60.5 Hz or
49.5-50.5 Hz for at least eight consecutive line cycles.
Set if the level now implemented by the dimmer came from the local
FOCUS button.
Set if the load current is too small to be accurately sensed, hence there
is no load or a very small load.
Set if at least one of the error flags in DIMMER ERRORS is now set.
– 55 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
B5.4 Dimmer Errors
2
3
4
5
6
7
The DIMMER ERRORS byte notes all fatal and non-fatal error conditions. Fatal conditions will also be flagged by lighting the
red LED on the dimmer. As soon as a fatal error has been reported, the dimmer will rerun its startup diagnostics in an
attempt to clear the error condition.
DIMMER ERRORS
has the following format:
8
BIT(S)
SIGNIFY
9
7
MISWIRE
10
6
WATCHDOG RESET
11
5
DIMMER POWER
SUPPLY
UNDERVOLT
12
4
TEMPERATURE
SHUTDOWN
13
3
OVERLOAD
SHUTDOWN
EXPLANATION
Set if dimmer power-up diagnostics sense a line voltage greater than
approximately 185 Vrms in 120V units (370 VRMS in 240V units),
indicating a likely miswire. (FATAL)
Set if dimmer firmware has been restarted after a software loop took too
long (>49.2 mS) to execute. This bit is automatically reset after 10
seconds.
Set if the dimmer's power supply output drops below a determined
value. This bit is reset when the supply output exceeds another
determined value, and the line voltage is at least 90 VRMS for 120 V
units (180 VRMS for 240V units).
Set if the dimmer is shutdown due to the temperature of the power
devices being too high or too low. Shutdown occurs if the temperature
is below -201 C or above 951 C. This condition is reset when the
temperature is in the range -15-901 C and the dimmer's operating level
has been set to zero by a level message or the FOCUS button.
Set if the dimmer has detected an overload (excessive current)
condition, either due to a short circuit or because the connected load
exceeds its rating, based on the CAPACITY field of its configuration
data:
Value of
CAPACITY
000
001
010
011
100
101
110
111
Overload if Full Output
= 120/220/230/240V
1700W
3300W
4900W
6500W
8200W
9800W
1700W
16300W
Output if Full
Output = 100V
1300W
2600W
3800W
5100W
6300W
7600W
1300W
12600W
This condition is reset when the dimmer's operating level has been set
to zero by a level message or by the FOCUS button; if the overload is
still present, the dimmer will shutdown again in several seconds.
14
2
NEGATIVE SWITCH
FAILURE
Set by power-up diagnostics if the negative power device conducts
current even when off. This condition can be detected only if a load is
present. (FATAL)
15
1
ROM CHECKSUM
FAILURE
Set by power-up diagnostics if the dimmer firmware shows an incorrect
checksum and may damaged. (FATAL)
16
0
ANALOG SECTION
FAILURE
Set by power-up diagnostics if the voltage or current sensing electronics
are non-functional. (FATAL)
– 56 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
B5.5 Dimmer Configuration
2
3
The dimmer configuration byte describes software- and hardware-selected configuration attributes, in the following format:
4
BIT(S)
SIGNIFY
5
7
NON-DIM
6
6
LINEAR VOLTAGE
7
5
FORCE FORWARD
PHASE CONTROL
Set if dimmer is forced to operate only in forward (conventional) phase
control mode; reset if dimmer is operating normally and chooses either
reverse or forward phase control based on the load type.
8
4
FORCE REDUCED
RISE/FALL
Set if dimmer is forced to operate with short (250 µS) rise/falltime; reset
if dimmer is operating normally and chooses appropriate rise/falltime
based on power device temperature.
9
3
240 VOLT
Set if 220/230/240V unit; reset if 100/120V unit. If the unit is a hybrid
120/240V dimmer, this bit indicates the present line voltage.
10
2-0
CAPACITY
Indicates the power handling capacity of the dimmer:
Explanation
Set if configured as a non-dim; cleared if configured as dimmer.
Set if linear voltage curve is selected; reset if standard or modified
square law.
Value of
CAPACITY
000
001
010
011
100
101
110
111
Output if Full Output
= 120/220/230/240V
1200W
2400W
3600W
4800W
6000W
7200W
1200W
12000W
Output if Full
Output = 100V
1000W
2000W
3000W
4000W
5000W
6000W
1000W
10000W
11
12
– 57 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
B5.6 Dimmer Detail
2
3
The DIMMER DETAIL byte provides additional status information, in the following format:
4
BIT(S)
SIGNIFY
5
7-6
RESERVED
Reserved by ET for future use; presently used for
debugging/maintenance information and should be ignored.
6
5
FPC CAUSE
When the dimmer reports an inductive load and has switched to
Forward Phase Control mode (see STATUS, above) this bit indicates
why the load was determined to be inductive. If cleared, the load
showed inductive characteristics during the first cycle of conduction; if
set, the load initially did not appear inductive, but a large number of
subsequent cycles showed large voltage kickbacks.
7
4
OVER 140 VOLTS
If set, the last line voltage determined exceeded 140 VRMS in 120V
units (280VRMS in 240V units) and cannot be reported accurately.
When this bit is set, line voltage will be reported as 140. Reset as soon
as the line voltage drops below 140VRMS in 120V units (280VRMS in
240V units).
8
3
NOT CONFIGURED
Set if the dimmer has just executed power-up diagnostics and requires
initialization by the associated headend processor. Note that this
condition can occur during normal operation if the headend and the
dimmer are operating on different power sources or phases, and only
the dimmer's power fails. This bit clears automatically after the dimmer
is re-initialized.
9
2
EXTENDED RISE/FALL
Set if dimmer is configured to support extended (800 µS) falltime and
device temperatures allow that mode to be used now.
10
1-0
OVERLOAD CAUSE
Specifies why an overload shutdown (see ERRORS above) occurred.
EXPLANATION
Code
00
Explanation
Too many hardware-detected overloads
(load current is not controllable)
01
Load has "warmed up" but size of load
exceeds dimmer's rated safe capacity
10
Unit is operating as a non-dim and has
detected too many inductive kickbacks
11
Load will not "warm up" - after 7-8 seconds
current has not dropped to valid level
11
12
13
14
15
16
17
18
19
20
21
22
B5.7 Dimmer Temperature
The DIMMER TEMPERATURE byte is an 8-bit unsigned number denoting the present temperature of one of the
dimmer's pair of power devices (where possible, the "case temperature" of the power device is what is
measured). The value is returned in degrees Centigrade, in the range 0-100; temperatures less than 0 will
report as 0, and temperatures greater than 100 will report as 100. The device temperature is updated once
per line cycle.
Note that a broken thermistor connection will cause the dimmer to report a temperature of 0. Any attempt to
bring the dimmer to a non-zero level with a missing or broken thermistor will cause a TEMPERATURE SHUTDOWN
(see ERRORS, above).
– 58 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
B5.8 Dimmer Load Size
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
The DIMMER LOAD size byte gives the dimmer's most recent determination of the size of the connected load.
The response is an 8-bit unsigned integer denoting the load size in hundred of watts. The load size is defined
as the rating printed on the lamp (i.e., power consumption at nominal full voltage), as opposed to the
instantaneous power being used by the lamp, which would vary with the level requested.
21
22
23
24
25
26
27
The DIMMER LEVEL byte is an 8-bit unsigned integer (range 0-255) denoting the present operating level. That
level may have been set through a DMX512 packet transmitted by the console, or from the action of the local
FOCUS button. If the dimmer is presently in TEMPERATURE SHUTDOWN or OVERLOAD SHUTDOWN (see ERRORS,
above), the level reported will be that which is presently requested, even though the dimmer is at zero
conduction.
28
29
30
31
32
33
34
35
36
37
38
39
DIMMER LINE VOLTAGE
Dimmers configured for 120V operation assume a nominal lamp voltage of 120V, unless full output voltage is
set to 100V, in which case the nominal lamp voltage is 100V. For 240V units, load sizes are computed for a
nominal lamp voltage that matches the set full output voltage of either 220V, 230V or 240V.
The load size is recomputed ever sixty line cycles, once the lamp has "warmed up" and is operating at a level
greater than or equal to 20% (i.e., a level value of 51 out of 255). The dimmer computes the load size from
the RMS load current, which may take a number of seconds to stabilize for very large lamps, hence there can
be a five to ten second delay after the lamp warms up before a new load size is reported.
Please note that reported load sizes are accurate to roughly +10%, and that many incandescent lamps have
a substantial manufacturing tolerance, consequently the reported size may not always exactly match the
value marked on the lamps.
B5.9 Dimmer Level
B5.10 Dimmer Line Voltage
notes the dimmer's most recent determination of the RMS line voltage as an 8-bit
unsigned integer. For 120V units (i.e., units that report configuration bit 240 VOLT as a zero), the value
returned is the voltage, in the range 0-140. For 240V units (i.e., 240 VOLT = 1), the value returned is one-half
of the voltage. If the line voltage exceeds the maximum specification (140 VRMS for 120V units; 280 VRMS
for 240V units), the dimmer cannot accurately determine the exact voltage, and will return the value 140 with
the OVER 140 VOLTS bit set in the response to DIMMER DETAIL.
The dimmer recomputes the line voltage once per line cycle, except during the lamp warmup and during load
size determination cycles.
-end of Annex B-
– 59 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
7KLV 3DJH $OPRVW %ODQN
– 60 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
be published in part or in whole or be duplicated for-profit or sold in any manner.
It may not
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Annex C (Normative) - Device Interconnection Table
The following table provides a means for identifying legitimate ways in which the interconnection of different
TYPEs of equipment may be made. It is a guide to whether the user may expect enhanced functionality of
interconnected products using Pins 4 & 5. Generally only like types provide increased functionality. Since
TYPE 1 is simply a device that passes through any signals present on Pins 4 & 5 (loop-through), the TYPE of
equipment upstream (transmitting) or downstream (receiving) of the TYPE 1 device must be examined to
determine functionality of the system.
If enhanced functionality is needed, a C2 Scheme cable is required and is equivalent to a TYPE 1 device.
For isolating conflicting uses of Pins 4 & 5, a C1 Scheme cable (equivalent to a TYPE 0 device) is used.
The interconnection of products using Accessory Power (+24 VDC) and claiming compliance with this
standard as DMX512/2000AP is outside the scope of this Standard. Such equipment requires the use of
special cables with an EIA-485 data pair and high current conductors. Such cables shall not be labeled as
DMX512 cables. Users of such products should refer to the manufacturers for guidance.
Table C - Interconnection cross-check (electrical / functional)
Rx
Legacy
Product
Tx
Rx
TYPE 0
Rx
TYPE 1
Rx
TYPE 2
Rx
TYPE 3
Rx
TYPE 4
Rx
TYPE 5
notes 1, 4
note 4
note 4
note 4
note 4
21
Legacy Product
22
Tx TYPE 0
23
Tx TYPE 1
notes 1, 4
note 1
note 1
note 1
note 1
note 1
24
Tx TYPE 2
note 4
note 1
note 2
note 6
note 6
note 6
25
Tx TYPE 3
note 4
note 1
note 6
note 2
note 6
note 6
26
Tx TYPE 4
note 4
note 1
note 6
note 6
note 3
note 6
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
Tx TYPE 5
note 4
note 1
note 6
note 6
note 6
note 3
note 4
note 5
note 5
Notes:
Blank Cell - No enhanced functionality possible. Use of a C1 (C5.1) Scheme cable is all that is required. Use of a
C2 (C5.2) scheme cable does no harm.
1)
2)
3)
4)
5)
6)
Loop-through (passive link) functionality when used with a C2 (C5.2) scheme cable. The TYPE of the
upstream (transmitting) or downstream (receiving) device must be examined.
Enhanced functionality requires use of C2 (C5.2) scheme cable.
Refer to manufacturers’ data, as enhanced functionality is unlikely with products of different
manufacturers. Enhanced functionality, requires use of C2 (C5.2) scheme cable.
Refer to manufacturers’ data, as enhanced functionality is unlikely with products of different
manufacturers. Enhanced functionality requires use of C2 (C5.2) scheme cable. Connection to legacy
product compliant with EIA-485 should not cause damage. Use of a C1 (C5.1) Scheme cable would
ensure no electrical damage or conflict is possible.
No enhanced functionality expected. Note that TYPE 5 equipment may be dependent of the existence
of signals on Pins 4 and 5 of the connected equipment for basic operation.
No enhanced functionality. Direct interconnection of these types of device should not cause electrical
failure as this has been covered by the limits for electrical protection defined in this Standard. Use of a
C1 (C5.1) Scheme cable would ensure no electrical damage or conflict.
-end of Annex C-
– 61 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
7KLV 3DJH $OPRVW %ODQN
– 62 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
be published in part or in whole or be duplicated for-profit or sold in any manner.
It may not
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
Annex D (Normative) - Port Marking Style Sheet
DESIGN CRITERIA
(1) Simple but informative
(2) Single color - to simplify silk screen applications – Manufacturer free to choose color
(3) Small enough to use adjacent to XLR connector
(4) Available as encapsulated postscript file and suitable for silkscreen at (typically) 60 dpi resolution
(5) TYPE and Grounding schemes shall be identified – Use of TYPE Symbols is optional
-end of Annex D– 63 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
7KLV 3DJH $OPRVW %ODQN
– 64 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
be published in part or in whole or be duplicated for-profit or sold in any manner.
It may not
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
1
2
3
4
5
Annex E (Normative) - Protocol Implementation Compliance Statement (PICS)
Manufacturers claiming compliance with this Standard shall complete and hold on file a Protocol
Implementation Compliance Statement (PICS) as defined in this Annex E. Copies of the PICS shall be made
available on request.
Question
6
7
#
Compliance
Reference
Page
Clause
Response
Lines
Y / N / NA Notes
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
-end of Annex E-
– 65 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
It may not
be published in part or in whole or be duplicated for-profit or sold in any manner.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
7KLV 3DJH $OPRVW %ODQN
– 66 –
© USITT / ESTA -This document is a work in progress, and may be duplicated only for the purposes of finalizing this Report.
be published in part or in whole or be duplicated for-profit or sold in any manner.
It may not
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
Inside Back Cover
ESTA Technical Standards Manager:
Karl Ruling
ESTA Control Protocols Working Group - Co-Chairs:
Steve Carlson, Rosco / ET
Steve Terry, Production Arts - Production Resource Group
ESTA Control Protocols Working Group - DMX512 Task Group Members:
Chair/Editor: Mitch Hefter, Rosco / ET; USITT (USA)
Canada
Dave Higgins, Gray Interfaces
USA
Tim Bachman, Barbizon Light
Steve Carlson, Rosco / ET
Milton Davis, Strand Lighting
Doug Fleenor, Doug Fleenor Design
Bob Goddard, Goddard Design
Ted Paget, Jones & Phillips
Steve Terry, Production Arts - Production Resource Group
Germany
Eckart Steffens, Soundlight; VPLT
UK
Tim Cox, PLASA
Tony Douglas-Beveridge, PLASA
Wayne Howell, Artistic Licence
Paul Mardon, Pulsar Light of Cambridge
Steve Unwin, Pulsar Light of Cambridge
Peter Willis, Andera Ltd.
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
'5$)7 Standard, BSR E1.11, Entertainment Technology - USITT DMX512 Asynchronous Serial Digital
Data Transmission Standard for Controlling Lighting Equipment and Accessories
%DFN &RYHU
CP98/1031r1.1a
'5$)7
Printed Nov 23, 1999 9:25 a
BSR E1.11, Entertainment Technology - USITT DMX512,
Asynchronous Serial Digital Data Transmission Standard
for Controlling Lighting Equipment and Accessories
Comments
submittal
form for:
(CP98/1031r1.1a)
Clause, page, and line numbers:
Proposed changes:
(Please use strikethrough to indicate deletions, and underline to indicate additions)
Substantiation:
I hereby grant ASC E1 and ESTA the non-exclusive, royalty-free rights to use my comments, and I understand that I acquire
no rights in any publication in which my comments are used.
Signature: _______________________________________
Date: ___________________________________________
Name: __________________________________________
(Please print)
City: ____________________________________________
State/Prov: _________________ Postal Code: ___________
Country: ________________________________________
Telephone: ______________________________________
Organization: _____________________________________
Fax: ___________________________________________
Street Address: ___________________________________
Email: __________________________________________
Please return the completed comments form to dmx-rfc@DesignRelief.com via e-mail, or mail it to:
Technical Standards Manager
ESTA
875 Sixth Avenue, Suite 2302
New York, NY 10001
Fax: 212-244-1502
Deadline for comments: 4:00 p.m. EST, January 12, 2000
CP/99-1016
Comment form instructions:
When commenting, please provide the following:
• clear identification of the relevant clause, page, and line numbers;
• the proposed change marked in legislative format, with strikethroughs to indicate deleted text and underlines to
indicate new text;
• substantiation for the change; and
• a wordprocessing file of the proposed changes (Word Perfect, Word 97 or lower, or RTF), with each
proposal on a separate page.
Please send yoru comments as electronic submissions to dmx-rfc@DesignRelief.com. If you want to mail hard copy
submissions, please send them to:
Technical Standards Manager
ESTA
875 Sixth Avenue, Suite 2302
New York, NY 10001
USA
Fax: +1-212-244-1502
All submissions must be received no later than 4:00 p.m. ET, January 12, 2000.
Background and what's new in this draft standard document:
The original version of the DMX512 standard was developed in 1986 by the Engineering Commission of the United
States Institute for Theatre Technology, Inc. (USITT). Minor revisions were made in 1990 to create "DMX512/1990,
Digital Data Transmission Standard for Dimmers and Controllers." The 1986 and 1990 versions covered only data
used by dimmers. In practice, the standard has been used for controlling a wide variety of devices.
In 1998 it became evident that additional updates to the standard were necessary and that formal recognition through
an internationally recognized standards organization was required. The USITT DMX512 Subcommittee issued a Call
for Comments in order to solicit recommendations for changes to the standard. At the same time, USITT transferred
maintenance of DMX512 to the Entertainment Services and Technology Association (ESTA).
The revision effort was taken up by the ESTA Technical Standards Program's Control Protocols Working Group,
which appointed a task group to act on the proposals received from USITT's Call for Comments. The task group
established several goals as part of their work:
1. Produce a consensus document following proper standards procedures.
2. Make editorial updates to DMX512 appropriate for current times.
3. Add technical features while maintaining a balance with backward compatibility, including formalizing the
management of alternate start codes.
4. Identify among the proposals received in response to the Call for Comments which ones belong in an
application note or a recommended practice instead of in the standard.
5. Take actions on these proposals and deliver a draft of a revised DMX512 standard to the Control Protocols
Working Group (CPWG).
New concepts introduced in this current draft standard include:
•
•
•
•
•
Structural changes to the written document, including the use of annexes
Definitions & terminology
Physical layer details / Earth grounding practices
DMX512 Types (classification of the uses of the second pair)
Protection
CP/99-1016
•
•
•
•
Marking of ports
Two distinct methods of delivering DC power
System information packet (e.g., checksums - Clause 7)
Alternate START code management
Changes already anticipated include the addition of an introductory overview clause and relocation of portions of the
body of the standard to annexes.
CP/99-1016
Source Exif Data:
File Type : PDF File Type Extension : pdf MIME Type : application/pdf PDF Version : 1.3 Linearized : Yes Encryption : Standard V1.2 (40-bit) User Access : Print, Copy, Fill forms, Extract, Assemble, Print high-res Create Date : 1999:11:23 09:28:06 Producer : Acrobat Distiller 3.02 Creator : PSCRIPT.DRV Version 4.0 Title : C:\DMX512\DMX Revisions\Drafts 2000\Draft r1.1a\DMX512-2000rev1.1a.wpd Modify Date : 1999:11:23 15:32:24-05:00 Page Count : 79EXIF Metadata provided by EXIF.tools