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maxon motor control
EPOS2 Positioning Controllers
Communication Guide
Edition May 2016
Positioning Controllers
Communication Guide
Document ID: rel5984
maxon motor ag Brünigstrasse 220 P.O.Box 263 CH-6072 Sachseln Phone +41 41 666 15 00 Fax +41 41 666 16 50 www.maxonmotor.com
PLEASE READ THIS FIRST
These instructions are intended for qualified technical personnel. Prior commencing with any
activities …
• you must carefully read and understand this manual and
• you must follow the instructions given therein.
We have tried to provide you with all information necessary to install and commission the equipment in a
secure, safe and time-saving manner. Our main focus is …
•
to familiarize you with all relevant technical aspects,
•
to let you know the easiest way of doing,
•
to alert you of any possibly dangerous situation you might encounter or that you might cause if
you do not follow the description,
•
to write as little and to say as much as possible and
•
not to bore you with things you already know.
Likewise, we tried to skip repetitive information! Thus, you will find things mentioned just once. If, for
example, an earlier mentioned action fits other occasions you then will be directed to that text passage
with a respective reference.
Follow any stated reference – observe respective information – then go back and continue with
the task!
PREREQUISITES FOR PERMISSION TO COMMENCE INSTALLATION
The EPOS2 is considered as partly completed machinery according to EU directive 2006/42/EC, Article
2, Clause (g) and therefore is intended to be incorporated into or assembled with other machinery
or other partly completed machinery or equipment.
You must not put the device into service, …
• unless you have made completely sure that the other machinery – the surrounding system the device
is intended to be incorporated to – fully complies with the requirements stated in the EU directive
2006/42/EC!
• unless the surrounding system fulfills all relevant health and safety aspects!
• unless all respective interfaces have been established and fulfill the stated requirements!
A-2
Document ID: rel5984
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maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
TABLE OF CONTENTS
1
About this Document
5
2
Introduction
7
2.1
Documentation Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3
EPOS2 Command Reference (USB & RS232)
3.1
9
Read Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.1.1 Read Object Dictionary Entry (4 Data Bytes and less) . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.1.2 Read Object Dictionary Entry (5 Data Bytes and more). . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.2
Write Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.2.1 Write Object Dictionary Entry (4 Data Bytes and less). . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.2.2 Write Object Dictionary Entry (5 Data Bytes and more). . . . . . . . . . . . . . . . . . . . . . . . . 11
3.2.3 NMT Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.3
4
General CAN Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
USB Communication
4.1
15
Data Link Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.1.1 Flow Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.1.2 Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.1.3 Error Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
4.1.4 Character Stuffing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.1.5 Transmission Byte Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.1.6 Timeout Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.1.7 Slave State Machine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.1.8 Example: Command Instruction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
4.2
5
Physical Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
RS232 Communication
5.1
21
Data Link Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
5.1.1 Flow Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
5.1.2 Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
5.1.3 Error Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.1.4 Transmission Byte Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.1.5 Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.1.6 Timeout Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
5.1.7 Slave State Machine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
5.1.8 Example: Command Instruction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
5.2
maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
Physical Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
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A-3
6
CAN Communication
6.1
29
General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
6.1.1 Documentation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
6.1.2 Notations, Abbreviations and Terms used. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
6.2
CANopen Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
6.2.1 Physical Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
6.2.2 Data Link Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
6.3
CANopen Application Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
6.3.1 Object Dictionary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
6.3.2 Communication Objects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
6.3.3 Predefined Communication Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
6.4
Identifier Allocation Scheme. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
7
Gateway Communication (USB & RS232 to CAN)
45
8
Error Code Definition
47
8.1
8.2
A-4
CANopen-specific Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
maxon-specific Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Document ID: rel5984
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maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
About this Document
1
About this Document
1.1
Intended Purpose
The purpose of the present document is to familiarize you with the described equipment and the tasks
on safe and adequate installation and/or commissioning.
Observing the described instructions in this document will help you …
•
to avoid dangerous situations,
•
to keep installation and/or commissioning time at a minimum and
•
to increase reliability and service life of the described equipment.
Use for other and/or additional purposes is not permitted. maxon motor, the manufacturer of the equipment described, does not assume any liability for loss or damage that may arise from any other and/or
additional use than the intended purpose.
1.2
Target Audience
This document is meant for trained and skilled personnel working with the equipment described. It conveys information on how to understand and fulfill the respective work and duties.
This document is a reference book. It does require particular knowledge and expertise specific to the
equipment described.
1.3
How to use
Take note of the following notations and codes which will be used throughout the document.
Notation
Explanation
«Abcd»
indicating a title or a name (such as of document, product, mode, etc.)
(n)
referring to an item (such as order number, list item, etc.)
denotes “see”, “see also”, “take note of” or “go to”
Table 1-1
Notations used in this Document
For CAN-specific notations, abbreviations and terms page 6-29.
maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
Document ID: rel5984
Edition: May 2016
© 2016 maxon motor. Subject to change without prior notice.
1-5
About this Document
1.4
Sources for additional Information
For further details and additional information, please refer to below listed sources:
#
1.5
Reference
[1]
CiA 301 Communication Profile for Industrial Systems
www.can-cia.org
[2]
CiA 402 Device Profile for Drives and Motion Control
www.can-cia.org
[3]
CiA 305 Layer Setting Services (LSS) and Protocols
www.can-cia.org
[4]
CiA 306 Electronic Data Sheet Specification
www.can-cia.org
[5]
Bosch’s CAN Specification 2.0
www.can-cia.org
[6]
USB Implementers Forum: Universal Serial Bus Revision 2.0 Specification
www.usb.org/developers/docs
[7]
Konrad Etschberger: Controller Area Network
ISBN 3-446-21776-2
[8]
maxon motor: EPOS2 Communication Guide
EPOS DVD-ROM or www.maxonmotor.com
Table 1-2
Sources for additional Information
Copyright
© 2016 maxon motor. All rights reserved.
The present document – including all parts thereof – is protected by copyright. Any use (including reproduction, translation, microfilming and other means of electronic data processing) beyond the narrow
restrictions of the copyright law without the prior approval of maxon motor ag, is not permitted and subject to persecution under the applicable law.
maxon motor ag
Brünigstrasse 220
P.O.Box 263
CH-6072 Sachseln
Switzerland
Phone +41 41 666 15 00
Fax +41 41 666 16 50
www.maxonmotor.com
1-6
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maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
Introduction
Documentation Structure
2
Introduction
The present document provides you with the communication interfaces details on the EPOS2 Positioning Controllers. It contains descriptions of the USB, RS232 and CAN interfaces.
maxon motor control’s EPOS2 is a small-sized, full digital, smart positioning control unit. Due to its flexible and high efficient power stage, the EPOS2 drives brushed DC motors with digital encoder as well as
brushless EC motors with digital Hall sensors and encoder.
The sinusoidal current commutation by space vector control offers to drive brushless EC motors with
minimal torque ripple and low noise. The integrated position, velocity and current control functionality
allows sophisticated positioning applications. It is specially designed to be commanded and controlled
as a slave node in the CANopen network. In addition, the unit can be operated through any USB or
RS232 communication port.
Find the latest edition of the present document, as well as additional documentation and software to the
EPOS2 Positioning Controllers also on the Internet: www.maxonmotor.com
2.1
Documentation Structure
The present document is part of a documentation set. Please find below an overview on the documentation hierarchy and the interrelationship of its individual parts:
Figure 2-1
maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
Documentation Structure
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2-7
Introduction
Documentation Structure
••page intentionally left blank••
2-8
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maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
EPOS2 Command Reference (USB & RS232)
Read Functions
3
EPOS2 Command Reference (USB & RS232)
3.1
Read Functions
3.1.1
Read Object Dictionary Entry (4 Data Bytes and less)
«ReadObject»
Read an object value from the Object Dictionary at the given Index and SubIndex.
Request Frame
0x10
OpCode
USB
RS232
Len
Len-1
Parameters
2
1
WORD Index
Index of Object
(Low) BYTE SubIndex
SubIndex of Object
(High) BYTE NodeId
Node ID
Response Frame
0x00
OpCode
USB
RS232
Len
Len-1
Parameters
3.1.2
4
3
DWORD ErrorCode
“Error Code Definition” on page 8-47
BYTE Data[4]
Data Bytes read
Read Object Dictionary Entry (5 Data Bytes and more)
«InitiateSegmentedRead»
Start reading an object value from the Object Dictionary at the given Index and SubIndex. Use the command “SegmentRead” to read the data.
Request Frame
0x12
OpCode
Len
Len-1
USB
RS232
Parameters
2
1
WORD Index
Index of Object
(Low) BYTE SubIndex
SubIndex of Object
(High) BYTE NodeId
Node ID
Response Frame
0x00
OpCode
Len
Len-1
Parameters
maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
USB
RS232
2
1
DWORD ErrorCode
“Error Code Definition” on page 8-47
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3-9
EPOS2 Command Reference (USB & RS232)
Write Functions
«SegmentRead»
Read a data segment of the object initiated with the command “InitiateSegmentedRead”.
Request Frame
0x14
OpCode
USB
RS232
Len
Len-1
1
0
not used [Bit 0…5]
(Low) BYTE ControlByte toggle
[Bit 6]
not used [Bit 7]
Parameters
(High) BYTE Dummy
–
Toggle Bit
–
Byte without meaning
Response Frame
0x00
OpCode
USB
RS232
Len
Len-1
3…34
2…33
DWORD ErrorCode
length
(Low) BYTE ControlByte toggle
more
Parameters
BYTE Data[0…63]
3.2
“Error Code Definition” on page 8-47
[Bit 0…5]
[Bit 6]
[Bit 7]
Number of data bytes
Toggle Bit
More segments to read
Data Bytes read
Write Functions
3.2.1
Write Object Dictionary Entry (4 Data Bytes and less)
«WriteObject»
Write an object value to the Object Dictionary at the given Index and SubIndex.
Request Frame
0x11
OpCode
Len
Len-1
USB
RS232
Parameters
4
3
WORD Index
Index of Object
(Low) BYTE SubIndex
SubIndex of Object
(High) BYTE NodeId
Node ID
BYTE Data[4]
Data Bytes to write
Response Frame
0x00
OpCode
Len
Len-1
Data
3-10
USB
RS232
2
1
DWORD ErrorCode
“Error Code Definition” on page 8-47
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maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
EPOS2 Command Reference (USB & RS232)
Write Functions
3.2.2
Write Object Dictionary Entry (5 Data Bytes and more)
«InitiateSegmentedWrite»
Start writing an object value to the Object Dictionary at the given Index and SubIndex. Use the command “SegmentWrite” to write the data.
Request Frame
0x13
OpCode
Len
Len-1
USB
RS232
Parameters
4
3
WORD Index
Index of Object
(Low) BYTE SubIndex
SubIndex of Object
(High) BYTE NodeId
Node ID
DWORD ObjectLength
Total number of bytes to write
Response Frame
0x00
OpCode
Len
Len-1
USB
RS232
2
1
DWORD ErrorCode
Data
“Error Code Definition” on page 8-47
«SegmentWrite»
Write a data segment to the object initiated with the command “InitiateSegmentedWrite”.
Request Frame
0x15
OpCode
Len
Len-1
USB
RS232
1…32
0…31
length
[Bit 0…5]
(Low) BYTE ControlByte toggle
[Bit 6]
not used [Bit 7]
Parameters
BYTE Data[0…63]
Number of data bytes
Toggle Bit
–
Data bytes to write
Response Frame
0x00
OpCode
Len
Len-1
Data
USB
RS232
3
2
DWORD ErrorCode
“Error Code Definition” on page 8-47
length
[Bit 0…5]
(Low) BYTE ControlByte toggle
[Bit 6]
not used [Bit 7]
(High) BYTE Dummy
maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
Number of data bytes
Toggle Bit
–
Byte without meaning
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3-11
EPOS2 Command Reference (USB & RS232)
Write Functions
3.2.3
NMT Service
«SendNMTService»
Send a NMT service to, for example, change NMT state or reset the device.
Request Frame
0x0E
OpCode
Len
Len-1
USB
RS232
Parameters
2
1
WORD NodeId
Node ID
WORD CmdSpecifier
1
2
128
129
130
Start Remote Node
Stop Remote Node
Enter Pre-Operational
Reset Node
Reset Communication
Response Frame *1)
0x00
OpCode
Len
Data
USB
2
DWORD ErrorCode
“Error Code Definition” on page 8-47
Remark: *1) no response with RS232
3-12
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maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
EPOS2 Command Reference (USB & RS232)
General CAN Commands
3.3
General CAN Commands
«SendCANFrame»
Send a general CAN Frame to the CAN Bus.
Request Frame
0x20
OpCode
Len
Len-1
USB
RS232
Parameters
6
5
WORD Identifier
CAN Frame 11-bit Identifier
WORD Length
CAN Frame Data Length Code (DLC)
BYTE Data[8]
CAN Frame Data
Response Frame *1)
0x00
OpCode
Len
USB
2
DWORD ErrorCode
Data
“Error Code Definition” on page 8-47
Remark: *1) no response with RS232
«RequestCANFrame»
Request a PDO/Guarding CAN Frame from a CAN Bus using Remote Transmit Request (RTR).
Request Frame
0x21
OpCode
Len
Len-1
USB
RS232
Parameters
2
1
WORD Identifier
CAN Frame 11-bit Identifier
WORD Length
CAN Frame Data Length Code (DLC)
Response Frame
0x00
OpCode
Len
Data
maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
USB
RS232
6
5
DWORD ErrorCode
“Error Code Definition” on page 8-47
BYTE Data[8]
CAN Frame Data
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3-13
EPOS2 Command Reference (USB & RS232)
General CAN Commands
«SendLSSFrame»
Send a LSS master message to the CAN Bus.
Request Frame
0x30
OpCode
Len
Len-1
USB
RS232
4
3
BYTE Data[8¨]
Parameters
LSS master message
Response Frame *1)
0x00
OpCode
Len
USB
2
DWORD ErrorCode
Data
“Error Code Definition” on page 8-47
Remark: *1) no response with RS232
«ReadLSSFrame»
Read a LSS slave message from the CAN Bus.
Request Frame
0x31
OpCode
Len
Len-1
USB
RS232
1
0
WORD Timeout
Parameters
Communication timeout [ms]
Response Frame
0x00
OpCode
Len
Data
3-14
USB
RS232
6
5
DWORD ErrorCode
“Error Code Definition” on page 8-47
BYTE Data[8¨]
LSS slave message
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maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
USB Communication
Data Link Layer
4
USB Communication
4.1
Data Link Layer
4.1.1
Flow Control
The EPOS2 Positioning Controllers always communicates as a slave. A frame is only sent as an answer
to a request. All EPOS2 commands send an answer. The master always must start the communication
by sending a packet structure.
Below described are the data flow while transmitting and receiving frames.
Figure 4-2
USB Communication – Command Sequence
Figure 4-3
USB Communication – Sending a Data Frame to EPOS2
Figure 4-4
USB Communication – Receiving a Response Data Frame from EPOS2
maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
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4-15
USB Communication
Data Link Layer
4.1.2
Frame Structure
The data bytes are sequentially transmitted in frames. A frame composes of…
•
a synchronization,
•
a header,
•
a variably long data field and
•
a 16-bit long cyclic redundancy check (CRC) for verification of data integrity.
“DLE”
(8-bit)
“STX”
(8-bit)
SYNC
Figure 4-5
SYNC
HEADER
DATA
Len
(8-bit)
Data[0]
(16-bit)
HEADER
Data[Len-1]
(16-bit)
…
DATA
CRC
(16-bit)
CRC
USB Communication – Frame Structure
The first two bytes are used for frame synchronization.
“DLE”
Starting frame character “DLE” (Data Link Escape) = 0x90
“STX”
Starting frame character “STX” (Start of Text) = 0x02
The header consists of 2 bytes. The first field determines the type of data frame to be sent
or received. The next field contains the length of the data fields.
OpCode
Operation command to be sent to the slave. For details on the command set
“EPOS2 Command Reference (USB & RS232)” on page 3-9.
Len
represents the number of words (16-bit value) in the data fields [0…143].
The data field contains the parameters of the message. The low byte of the word is
transmitted first.
Data[i]
CRC
OpCode
(8-bit)
The parameter word of the command. The low byte is transmitted first.
The 16-bit CRC checksum using the algorithm CRC-CCITT.
The CRC calculation includes all bytes of the frame except the synchronization bytes, the
data bytes must be calculated as a word.
First, you will need to shift to the data word’s high byte.
This represents the opposite way as you transmit the data word.
For calculation, the 16-bit generator polynomial “x16+x12+x5+1” is used.
CRC
Checksum of the frame. The low byte is transmitted first.
Note
The CRC is calculated before stuffing the data. The elements “OpCode” to “Data[Len-1]” are included in
CRC calculation. The synchronization elements “DLE” and “STX” are not included.
4-16
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maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
USB Communication
Data Link Layer
4.1.3
Error Control
4.1.3.1
Acknowledge
As a reaction to a bad OpCode or CRC value, the slave sends a frame containing the corresponding
error code.
4.1.3.2
CRC Calculation
Packet M(x):
WORD DataArray[n]
Generator Polynom G(x):
10001000000100001 (= x16+x12+x5+x0)
DataArray[0]:
DataArray[1]:
DataArray[2]:
…
DataArray[n-1]:
HighByte(Len) + LowByte(OpCode)
Data[0]
Data[1]
…
0x0000 (ZeroWord)
WORD CalcFieldCRC(WORD* pDataArray, WORD numberOfWords)
{
WORD shifter, c;
WORD carry;
WORD CRC = 0;
//Calculate pDataArray Word by
Word
while(numberOfWords−−)
{
shifter = 0x8000;
//Initialize BitX to Bit15
c = *pDataArray++;
//Copy next DataWord to c
do
{
carry = CRC & 0x8000;
//Check if Bit15 of CRC is set
CRC <<= 1;
//CRC = CRC * 2
if(c & shifter) CRC++;
//CRC = CRC + 1, if BitX is set in c
if(carry) CRC ^= 0x1021;
//CRC = CRC XOR G(x), if carry is true
shifter >>= 1;
//Set BitX to next lower Bit, shifter = shifter/2
} while(shifter);
}
return CRC
}
Figure 4-6
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USB Communication – CRC Calculation
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4-17
USB Communication
Data Link Layer
4.1.4
Character Stuffing
The sequence “DLE” and “STX” are reserved for frame start synchronization. If the character “DLE”
appears at a position between “OpCode” and “CRC” and is not a starting character, the character must
be doubled (character stuffing). Otherwise, the protocol begins to synchronize for a new frame. The
character “STX” needs not to be doubled.
Examples:
Sending Data
0x21, 0x90, 0x45
Stuffed Data
0x21, 0x90, 0x90, 0x45
Sending Data
0x21, 0x90, 0x02, 0x45
Stuffed Data
0x21, 0x90, 0x90, 0x02, 0x45
Sending Data
0x21, 0x90, 0x90, 0x45
Stuffed Data
0x21, 0x90, 0x90, 0x90, 0x90, 0x45
Important:
Character stuffing is used for all bytes in the frame except the starting characters.
4.1.5
Transmission Byte Order
The unit of data memory in EPOS2 is a word (16-bit value). To send and receive a word (16-bit) via the
serial port, the low byte will be transmitted first.
Multiple byte data (word = 2 bytes, long words = 4 bytes) are transmitted starting with the less significant
byte (LSB) first.
A word will be transmitted in following order: byte0 (LSB), byte1 (MSB).
A long word will be transmitted in following order: byte0 (LSB), byte1, byte2, byte3 (MSB).
4.1.6
Timeout Handling
The timeout is handled over a complete frame. Hence, the timeout is evaluated over the sent data
frame, the command processing procedure and the response data frame. For each frame (frames, data
processing), the timer is reset and timeout handling will recommence.
Object
Index
SubIndex
Default
USB Frame Timeout
0x2006
0x00
500 [ms]
Table 4-3
USB Communication – Timeout Handling
Note
To cover special requirements, the timeout may be changed by writing to the Object Dictionary!
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USB Communication
Data Link Layer
4.1.7
Slave State Machine
Figure 4-7
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4-19
USB Communication
Physical Layer
4.1.8
Example: Command Instruction
The following example shows composition and structure of the EPOS2 messages during transmission
and reception via USB. The command sent to the EPOS2 is “ReadObject”, it may be used to read an
object with 4 Bytes and less.
ReadObject “Home Offset” (Index = 0x2081, SubIndex = 0x00)
“DLE”
“STX”
OpCode
Len
Data[0]
Data[1]
CRC
0x90
0x02
0x10
0x02
0x2081
0x0100
0x870F
DLE
STX
OpCode
Data[0]
LowByte data[1]
HighByte data[1]
0x90
0x02
0x10
0x2081
0x00
0x01
Table 4-4
= Data Link Escape
= Start of Text
= ReadObject
= 2 Words
= SubIndex
= Node ID
ReadObject “Home Offset”
Transmission Order: 0x90,0x02,0x10,0x02,0x81,0x20,0x00,0x01,0x0F,0x87.
The EPOS2 will answer to the command “ReadObject” with an answer frame and the returned parameters in the data block as follows:
Answer to ReadObject “Home Offset” (Index = 0x2081, SubIndex = 0x00)
“DLE”
“STX”
OpCode
Len-1
Data[0]
Data[1]
Data[2]
Data[3]
CRC
0x90
0x02
0x00
0x04
0x0000
0x0000
0x0000
0x8090
0x3514
DLE
STX
OpCode
Len
Data[0]
Data[1]
Data[2]
Data[3]
Table 4-5
0x90
0x02
0x00
0x04
0x0000
0x0000
0x0000
0x8090
= Data Link Escape
= Start of Text
= Answer
= 4 Words
= LowWord ErrorCode
= HighWord ErrorCode
= Value of Object “HomeOffset”
= Word without meaning
Answer to ReadObject “Home Offset”
Reception Order: 0x90,0x02,0x00,0x04,0x00,0x00,0x00,0x00,0x00,0x00,0x90,0x90,0x80,0x14,0x35
Note
Observe character stuffing methodology (“Character Stuffing” on page 4-18).
4.2
Physical Layer
Electrical Standard
maxon EPOS2 drives’ USB interface follows the «Universal Serial Bus Specification Revision 2.0». You
may wish to download the file from the Internet (for URL “Sources for additional Information” on
page 1-6), full details are described in chapter “7.3 Physical Layer”.
4-20
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EPOS2 Communication Guide
RS232 Communication
Data Link Layer
5
RS232 Communication
The serial EIA RS232 communication protocol is used to transmit and receive data over the EPOS2’s
RS232 serial port. Its principal task is to transmit data from a master (PC or any other central processing
unit) to a single slave. The protocol is defined or point-to-point communication based on the EIA-RS232
standard.
The protocol can be used to implement the command set defined for the EPOS2. For a high degree of
reliability in an electrically noisy environment, it features a checksum.
5.1
Data Link Layer
5.1.1
Flow Control
5.1.1.1
Sequence for sending EPOS2 Commands
The EPOS2 Positioning Controllers always communicates as a slave. A frame is only sent as an answer
to a request. Some EPOS2 commands send an answer, other commands do not (observe respective
descriptions to determine command that send an answer packets). The master always must start the
communication by sending a packet structure.
Below described are the data flow while transmitting and receiving frame.
Figure 5-8
5.1.1.2
RS232 Communication – Command Sequence
Sending a Data Frame
When sending a frame, you will need to wait for different acknowledgment.
a) After sending the first frame byte (OpCode), you will need to wait for the EPOS2’s “Ready
Acknowledge”.
b) Once the character “O” (okay) is received, the slave is ready to receive further data.
c) If the character “F” (failed) is received, the slave is not ready to send data and communication
must be stopped.
d) After sending the checksum, you will need to wait for the “End Acknowledge”. The slave
sends either “O” (okay) or “F” (failed).
For the interaction while sending a packet structure Figure 5-9.
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5-21
RS232 Communication
Data Link Layer
Figure 5-9
5.1.1.3
RS232 Communication – Sending a Data Frame to EPOS2
Receiving a Data Frame
In response to some of the command frames, the EPOS2 returns a response data frame to the master.
The data flow sequence is identical as for sending a data packet, only in the other direction. The master
must also send the two acknowledges to the slave.
a) The value of the first field must always be 0x00, thus representing the operation code describing a response frame.
b) After receiving the first byte, the master then must send the “Ready Acknowledge”.
c) Send character “O” (okay) if you are ready to receive the rest of the frame.
d) Send character “F” (failed) if you are not ready to receive the rest of the frame.
e) If the EPOS2 does not get an “O” within the specified timeout, the communication is reset.
Sending “F” does not reset the communication.
f) After sending the “Ready Acknowledge” (“O”), EPOS2 sends the rest of the data frame. Then
the checksum must be calculated and compared with the one received. If the checksum is
correct, send acknowledge “O” to the EPOS2, otherwise send acknowledge “F”.
Figure 5-10
5-22
RS232 Communication – Receiving a Response Data Frame from EPOS2
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RS232 Communication
Data Link Layer
5.1.2
Frame Structure
The data bytes are sequentially transmitted in frames. A frame composes of…
•
a header,
•
a variably long data field and
•
a 16-bit long cyclic redundancy check (CRC) for verification of data integrity.
OpCode
(8-bit)
Len-1
(8-bit)
Data[0]
(16-bit)
HEADER
Figure 5-11
HEADER
DATA
Data[Len-1]
(16-bit)
DATA
CRC
16-bit
CRC
RS232 Communication – Frame Structure
The header consists of 2 bytes. The first field determines the type of data frame to be sent
or received. The next field contains the length of the data fields.
OpCode
Operation command to be sent to the slave. For details on the command set
“EPOS2 Command Reference (USB & RS232)” on page 3-9.
Len-1
represents the number of words (16-bit value) in the data fields.
It contains the number of words minus one. The smallest value in this field is
zero, which represents a data length of one word. The data block must
contain at least 1 word.
Examples:
1 word: Len-1 = 0
2 words: Len-1 = 1
256 words: Len-1 = 255
The data field contains the parameters of the message. This data block must contain at
least one word. The low byte of the word is transmitted first.
Data[i]
CRC
…
The parameter word of the command. The low byte is transmitted first.
The 16-bit CRC checksum. The algorithm used is CRC-CCITT. The CRC calculation
includes all bytes of the frame. The data bytes must be calculated as a word.
First you will need to shift in the high byte of the data word.
This is the opposite way you transmit the data word.
The 16-bit generator polynomial “x16+x12+x5+1” is used for the calculation.
Order of CRC calculation:
“OpCode”, “len-1”, “data[0]” high byte, “data[0]” low byte, …, ZeroWord low byte = 0x00,
ZeroWord high byte = 0x00
CRC
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Checksum of the frame. The low byte is transmitted first.
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5-23
RS232 Communication
Data Link Layer
5.1.3
Error Control
5.1.3.1
CRC Calculation
Packet M(x):
WORD DataArray[n]
Generator Polynom G(x):
10001000000100001 (= x16+x12+x5+x0)
DataArray[0]:
DataArray[1]:
DataArray[2]:
…
DataArray[n-1]:
HighByte(OpCode) + LowByte(len-1)
Data[0]
Data[1]
…
0x0000 (ZeroWord)
WORD CalcFieldCRC(WORD* pDataArray, WORD numberOfWords)
{
WORD shifter, c;
WORD carry;
WORD CRC = 0;
//Calculate pDataArray Word by Word
while(numberOfWords−−)
{
shifter = 0x8000;
//Initialize BitX to Bit15
c = *pDataArray++;
//Copy next DataWord to c
do
{
carry = CRC & 0x8000;
//Check if Bit15 of CRC is set
CRC <<= 1;
//CRC = CRC * 2
if(c & shifter) CRC++;
//CRC = CRC + 1, if BitX is set in c
if(carry) CRC ^= 0x1021;
//CRC = CRC XOR G(x), if carry is true
shifter >>= 1;
//Set BitX to next lower Bit, shifter = shifter/2
} while(shifter);
}
return CRC
}
Figure 5-12
5.1.4
RS232 Communication – CRC-CCITT Calculation
Transmission Byte Order
The unit of data memory in EPOS2 is a word (16-bit value). To send and receive a word (16-bit) via the
serial port, the low byte will be transmitted first.
Multiple byte data (word = 2 bytes, long words = 4 bytes) are transmitted starting with the less significant
byte (LSB) first.
A word will be transmitted in following order: byte0 (LSB), byte1 (MSB).
A long word will be transmitted in following order: byte0 (LSB), byte1, byte2, byte3 (MSB).
5.1.5
Data Format
Data is transmitted in an asynchronous way, thus each data byte is transmitted individually with its own
start and stop bit. The format is 1 Start bit, 8 Data bits, No parity, 1 Stop bit. Most serial communication
chips (SCI, UART) can generate such data format.
5-24
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EPOS2 Communication Guide
RS232 Communication
Data Link Layer
5.1.6
Timeout Handling
The timeout is handled over a complete frame. Hence, the timeout is evaluated over the sent data
frame, the command processing procedure and the response data frame. For each frame (frames, data
processing), the timer is reset and timeout handling will recommence.
Object
Index
SubIndex
Default
RS232 Frame Timeout
0x2005
0x00
500 [ms]
Table 5-6
RS232 Communication – Timeout Handling
Note
To cover special requirements, the timeout may be changed by writing to the Object Dictionary!
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5-25
RS232 Communication
Data Link Layer
5.1.7
Slave State Machine
Figure 5-13
5-26
RS232 Communication – Slave State Machine
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RS232 Communication
Data Link Layer
5.1.8
Example: Command Instruction
The following example shows composition and structure of the EPOS2 messages during transmission
and reception via serial RS232. The command sent to the EPOS2 is “ReadObject”, it may be used to
read an object with 4 Bytes and less.
ReadObject “Software Version” (Index = 0x2003, SubIndex = 0x01)
OpCode
Len-1
Data[0]
Data[1]
CRC
0x10
0x01
0x2003
0x0201
0xA888
OpCode
Len-1
Data[0]
LowByte data[1]
HighByte data[1]
Table 5-7
0x10
0x01
0x2003
0x01
0x02
= ReadObject
= 2 Words
= Index
= SubIndex
= Node ID
ReadObject “Software Version”
Transmission Order: 0x10,0x01,0x03,0x20,0x01,0x02,0x88,0xA8.
The EPOS2 answers to the command ReadObject with an answer frame and the returned parameters in
the data block as follows:
Answer to ReadObject “Software Version” (Index = 0x2003, SubIndex = 0x01)
OpCode
Len-1
Data[0]
Data[1]
Data[2]
Data[3]
CRC
0x00
0x03
0x0000
0x0000
0x2010
0x6210
0x2610
OpCode
Len-1
Data[0]
Data[1]
Data[2]
Data[3]
Table 5-8
0x00
0x03
0x0000
0x0000
0x2010
0x6210
= Answer
= 4 Words
= LowWord ErrorCode
= HighWord ErrorCode
= Value of Object “SoftwareVersion”
= Word without meaning
Answer to ReadObject “Software Version”
Reception Order: 0x00,0x03,0x00,0x00,0x00,0x00,0x10,0x20,0x10,0x62,0x10,0x26
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RS232 Communication
Physical Layer
5.2
Physical Layer
Electrical Standard
The EPOS2 communication protocol uses the RS232 standard to transmit data over a 3-wire cable (signals TxD, RxD and GND).
The RS232 standard can only be used for point-to-point communication between a master and a single
EPOS2 slave. It uses negative, bipolar logic with a negative voltage signal representing a logic “1”, and
positive voltage representing a logic “0”. Voltages of −3…−25 V with respect to signal ground (GND) are
considered logic “1”, whereas voltages of +3…25 V are considered logic “0”.
Medium
For the physical connection, a 3-wire cable will be required. We recommend to install a shielded and
twisted pair cable in order to achieve good performance, even in an electrically noisy environment.
Depending on the bit rate used, the cable length can range from 3…15 meters. However, we do not recommend to use RS232 cables longer than 5 meters.
5-28
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CAN Communication
General Information
6
CAN Communication
6.1
General Information
maxon EPOS2 drives’ CAN interface follows the CiA CANopen specifications…
•
CiA 301 V4.2 Communication Profile for Industrial Systems and
•
CiA 402 V3.0 Device Profile for Drives and Motion Control.
6.1.1
Documentation
For further information on CAN/CANopen as well as respective specifications listed references in
chapter “1.4 Sources for additional Information” on page 1-6.
6.1.2
Notations, Abbreviations and Terms used
Notation
Description
Format
nnnnb
Numbers followed by “b”.
binary
nnnnh
Numbers followed by “h”.
hexadecimal
nnnn
All other numbers.
decimal
Table 6-9
CAN Communication – Notations
Abbreviation
Description
CAN
CAN Application Layer
CMS
CAN Message Specification
COB
Communication Object (CAN Message) – a unit of transportation in a CAN message
network. Data must be sent across a network inside a COB.
COB-ID
COB Identifier – identifies a COB uniquely in a network and determines the priority
of that COB in the MAC sublayer.
EDS
Electronic Data Sheet – a standard form of all CAN objects supported by a device.
Used by external CAN configurators.
ID
Identifier – the name by which a CAN device is addressed.
MAC
Medium Access Control – one of the sublayers of the Data Link Layer in the CAN
Reference Model. Controls the medium permitted to send a message.
OD
Object Dictionary – the full set of objects supported by the node. Represents the
interface between application and communication (term “Object” on page 6-30).
PDO
Process Data Object – object for data exchange between several devices.
PLC
Programmable Controller – can serve as a CAN Master for the EPOS2.
RO
Read Only
RW
Read Write
SDO
Service Data Object – peer-to-peer communication with access to the device’s
Object Directory.
WO
Write Only
Table 6-10
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EPOS2 Communication Guide
CAN Communication – Abbreviations
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6-29
CAN Communication
General Information
Term
Description
CAN Client
or
CAN Master
A host (typically a PC or other control equipment) supervising the nodes of a
network.
CAN Server
or
CAN Slave
A node in the CAN network that can provide service under the CAN Master’s
control.
Object
A CAN message with meaningful functionality and/or data. Objects are referenced
according to addresses in the Object Dictionary.
Receive
“received” data is being sent from the control equipment to the EPOS2.
Transmit
“transmitted” data is being sent from the EPOS2 to the other equipment.
Table 6-11
6-30
CAN Communication – Terms
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CAN Communication
CANopen Basics
6.2
CANopen Basics
Subsequently described are the CANopen communication features most relevant to the maxon motor’s
EPOS2 Positioning Controllerss. For more detailed information consult above mentioned CANopen documentation.
The CANopen communication concept can be described similar to the ISO Open Systems Interconnection (OSI) Reference Model. CANopen represents a standardized application layer and communication
profile.
Figure 6-14
6.2.1
CAN Communication – Protocol Layer Interactions
Physical Layer
CANopen is a networking system based on the CAN serial bus. It assumes that the device’s hardware
features a CAN transceiver and a CAN controller as specified in ISO 11898. The physical medium is a
differently driven 2-wire bus line with common return.
Figure 6-15
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CAN Communication
CANopen Basics
6.2.2
Data Link Layer
The CAN data link layer is also standardized in ISO 11898. Its services are implemented in the Logical
Link Control (LLC) and Medium Access Control (MAC) sublayers of a CAN controller.
•
The LLC provides acceptance filtering, overload notification and recovery management.
•
The MAC is responsible for data encapsulation (decapsulation), frame coding (stuffing/destuffing), medium access management, error detection, error signaling, acknowledgment, and serialization (deserialization).
A Data Frame is produced by a CAN node when the node intends to transmit data or if this is requested
by another node. Within one frame, up to 8 byte data can be transported.
Figure 6-16
CAN Communication – CAN Data Frame
•
The Data Frame begins with a dominant Start of Frame (SOF) bit for hard synchronization of all
nodes.
•
The SOF bit is followed by the Arbitration Field reflecting content and priority of the message.
•
The next field – the Control Field – specifies mainly the number of bytes of data contained in the
message.
•
The Cyclic Redundancy Check (CRC) field is used to detect possible transmission errors. It consists of a 15-bit CRC sequence completed by the recessive CRC delimiter bit.
•
During the Acknowledgment (ACK) field, the transmitting node sends out a recessive bit. Any
node that has received an error-free frame acknowledges the correct reception of the frame by
returning a dominant bit.
•
The recessive bits of the End of Frame (EOF) terminate the Data Frame. Between two frames, a
recessive 3-bit Intermission field must be present.
With EPOS2, only the Standard Frame Format is supported.
Figure 6-17
6-32
CAN Communication – Standard Frame Format
•
The Identifier’s (COB-ID) length in the Standard Format is 11 bit.
•
The Identifier is followed by the RTR (Remote Transmission Request) bit. In Data Frames, the
RTR bit must be dominant, within a Remote Frame, the RTR bit must be recessive.
•
The Base ID is followed by the IDE (Identifier Extension) bit transmitted dominant in the Standard
Format (within the Control Field).
•
The Control Field in Standard Format includes the Data Length Code (DLC), the IDE bit, which is
transmitted dominant and the reserved bit r0, also transmitted dominant.
•
The reserved bits must be sent dominant, but receivers accept dominant and recessive bits in all
combinations.
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CAN Communication
CANopen Application Layer
6.3
CANopen Application Layer
6.3.1
Object Dictionary
The most significant part of a CANopen device is the Object Dictionary. It is essentially a grouping of
objects accessible via the network in an ordered, predefined fashion. Each object within the dictionary is
addressed using a 16-bit index and a 8-bit subindex. The overall layout of the standard Object Dictionary conforms to other industrial field bus concepts.
Index
Variable accessed
0000h
Reserved
0001h-009Fh
Data types (not supported on EPOS2)
00A0h-0FFFh
Reserved
1000h-1FFFh
Communication Profile Area (CiA 301)
2000h-5FFFh
Manufacturer-specific Profile Area (maxon motor
6000h-9FFFh
Standardized Device Area (CiA 402)
A000h-FFFFh
Reserved
Table 6-12
CAN Communication – Object Dictionary Layout
A 16-bit index is used to address all entries within the Object Dictionary. In case of a simple variable, it
references the value of this variable directly. In case of records and arrays however, the index
addresses the entire data structure. The subindex permits individual elements of a data structure to be
accessed via the network.
•
For single Object Dictionary entries (such as UNSIGNED8, BOOLEAN, INTEGER32, etc.), the
subindex value is always zero.
•
For complex Object Dictionary entries (such as arrays or records with multiple data fields), the
subindex references fields within a data structure pointed to by the main index.
An example: A receive PDO, the data structure at index 1400h defines the communication parameters
for that module. This structure contains fields or the COB-ID and the transmission type. The subindex
concept can be used to access these individual fields as shown below.
Index
SubIndex
Variable accessed
Data Type
1400h
0
Number of entries
UNSIGNED8
1400h
0
COB-ID receive PDO1
UNSIGNED32
1400h
2
Transmission type receive PDO1
UNSIGNED8
Table 6-13
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6-33
CAN Communication
CANopen Application Layer
6.3.2
Communication Objects
CANopen communication objects are described by the services and protocols. They are classified as
follows:
•
The real-time data transfer is performed by means of Process Data Objects.
•
With Service Data Objects, read/write access to entries of a device Object Dictionary is provided.
•
Special Function Objects provide application-specific network synchronization and emergency
messages.
•
Network Management Objects provide services for network initialization, error control and device
status control.
Communication Objects
Process Data Objects (PDO)
Service Data Objects (SDO)
Special Function Objects
Synchronization Objects (SYNC)
Network Management Objects
Table 6-14
6.3.3
Time Stamp Objects (not used on EPOS2)
Emergency Objects (EMCY)
NMT Message
Node Guarding Object
CAN Communication – Communication Objects
Predefined Communication Objects
6.3.3.1
PDO Object
PDO communication can be described by the producer/consumer model. Process data can be transmitted from one device (producer) to one another device (consumer) or to numerous other devices (broadcasting). PDOs are transmitted in a non-confirmed mode. The producer sends a Transmit PDO
(TxPDO) with a specific identifier that corresponds to the identifier of the Receive PDO (RxPDO) of one
or more consumers.
Figure 6-18
CAN Communication – Process Data Object
There are two PDO services:
•
The Write PDO is mapped to a single CAN Data frame.
•
The Read PDO is mapped to CAN Remote Frame, which will be responded by the corresponding
CAN Data Frame.
Read PDOs are optional and depend on the device capability. The complete data field of up to 8 byte
may contain process data. Number and length of a device’s PDOs are application-specific and must be
specified in the device profile.
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CAN Communication
CANopen Application Layer
The number of supported PDOs is accessible at the Object Dictionary’s index 1004h. The PDOs correspond to entries in the Object Dictionary and serve as interface to application objects. Application
objects’ data type and mapping into a PDO is determined by a corresponding default PDO mapping
structure within the Object Dictionary. This structure is defined in the entries “1600h” (for the first
R_PDO) and “1A00h” (for the first T_PDO). In a CANopen network, up to 512 T_PDOs and 512
R_PDOs may be used.
Figure 6-19
CAN Communication – PDO Protocol
The CANopen communication profile distinguishes three message triggering modes:
a) Message transmission is triggered by the occurrence of an object-specific event specified in
the device profile.
b) The transmission of asynchronous PDOs may be initiated upon receipt of a remote request
initiated by another device.
c) Synchronous PDOs are triggered by the expiration of a specified transmission period synchronized by the reception of the SYNC object.
Figure 6-20
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CAN Communication
CANopen Application Layer
6.3.3.2
SDO Object
With Service Data Objects (SDOs), the access to entries of a device Object Dictionary is provided. A
SDO is mapped to two CAN Data Frames with different identifiers, because communication is confirmed. By means of a SDO, a peer-to-peer communication channel between two devices may be established. The owner of the accessed Object Dictionary is the server of the SDO. A device may support
more than one SDO, one supported SDO is mandatory and the default case.
Figure 6-21
CAN Communication – Service Data Object
Read and write access to the CANopen Object Dictionary is performed by SDOs. The Client/Server
Command Specifier contains the following information:
•
download/upload
•
request/response
•
segmented/expedited transfer
•
number of data bytes
•
end indicator
•
alternating toggle bit for each subsequent segment
SDOs are described by the communication parameter. The default Server SDO (S_SDO) is defined in
the entry “1200h”. In a CANopen network, up to 256 SDO channels requiring two CAN identifiers each
may be used.
Figure 6-22
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CAN Communication – Object Dictionary Access
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CAN Communication
CANopen Application Layer
6.3.3.3
SYNC Object
The SYNC producer provides the synchronization signal for the SYNC consumer.
As the SYNC consumers receive the signal, they will commence carrying out their synchronous tasks. In
general, fixing of the transmission time of synchronous PDO messages coupled with the periodicity of
the SYNC Object’s transmission guarantees that sensors may arrange sampling of process variables
and that actuators may apply their actuation in a coordinated manner. The identifier of the SYNC Object
is available at index “1005h”.
Figure 6-23
CAN Communication – Synchronization Object
Synchronous transmission of a PDO means that the transmission is fixed in time with respect to the
transmission of the SYNC Object. The synchronous PDO is transmitted within a given time window “synchronous window length” with respect to the SYNC transmission and, at the most, once for every period
of the SYNC. The time period between SYNC objects is specified by the parameter “communication
cycle period”.
CANopen distinguishes the following transmission modes:
•
synchronous transmission
•
asynchronous transmission
Synchronous PDOs are transmitted within the synchronous window after the SYNC object. The priority
of synchronous PDOs is higher than the priority of asynchronous PDOs.
Asynchronous PDOs and SDOs can be transmitted at every time with respect to their priority. Hence,
they may also be transmitted within the synchronous window.
Figure 6-24
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CAN Communication – Synchronous PDO
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CAN Communication
CANopen Application Layer
6.3.3.4
EMERGENCY Object
Emergency messages are triggered by the occurrence of a device internal fatal error. They are transmitted by the concerned device to the other devices with high priority, thus making them suitable for interrupt type error alerts.
An Emergency Telegram may be sent only once per “error event”, i.e. the emergency messages must
not be repeated. As long as no new errors occur on a Enter Pre-Operational device, no further emergency message must be sent. The error register as well as additional, device-specific information are
specified in the device profiles by means of emergency error codes defined as to CANopen Communication Profile.
Figure 6-25
6.3.3.5
CAN Communication – Emergency Service
NMT Services
The CANopen network management is node-oriented and follows a master/slave structure. It requires
one device in the network that fulfils the function of the NMT Master. The other nodes are NMT Slaves.
Network management provides the following functionality groups:
•
Module Control Services for initialization of NMT Slaves that want to take part in the distributed
application.
•
Error Control Services for supervision of nodes’ and network’s communication status.
•
Configuration Control Services for up/downloading of configuration data from/to a network module.
A NMT Slave represents that part of a node, which is responsible for the node’s NMT functionality. It is
uniquely identified by its module ID.
Figure 6-26
CAN Communication – Network Management (NMT)
The CANopen NMT Slave devices implement a state machine that automatically brings every device to
“Pre-Operational” state, once powered and initialized.
In “Pre-Operational” state, the node may be configured and parameterized via SDO (e.g. using a configuration tool), PDO communication is not permitted. The NMT Master may switch from “Pre-Operational”
to “Operational”, and vice versa.
In “Operational” state, PDO transfer is permitted. By switching a device into “Stopped” state it will be
forced to stop PDO and SDO communication. Furthermore, “Operational” can be used to achieve certain application behavior. The behavior's definition is part of the device profile’s scope. In “Operational”,
all communication objects are active. Object Dictionary access via SDO is possible. However, implementation aspects or the application state machine may require to switching off or to read only certain
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EPOS2 Communication Guide
CAN Communication
CANopen Application Layer
application objects while being operational (e.g. an object may contain the application program, which
cannot be changed during execution).
Figure 6-27
CAN Communication – NMT Slave State Diagram
CANopen Network Management provides the following five services, which can be distinguished by the
Command Specifier (CS).
Remarks:
*1)
*2)
*3)
Command may be sent with Network Management (NMT) Protocol.
This Transition is generated automatically by the EPOS2 after initialization is completed.
After initialization a Boot-Up message is send.
Remote flag Bit 9 of the Statusword.
Transi- NMT State after
tion
Command
Remote
*1
–*2
0
Pre-Operational
FALSE
Enter
Pre-Operational
3, 6
Pre-Operational
FALSE
Service
Reset
Communication
Reset Node
*3
Functionality
Communication:
– Service Data Objects (SDO) Protocol
– Emergency Objects
– Network Management (NMT) Protocol
1, 8, 9
Initialization
FALSE
(Pre-Operational)
Calculates SDO COB-IDs.
Setup Dynamic PDO-Mapping and calculates PDO COB-IDs.
Communication:
– While initialization is active, no communication is supported.
– Upon completion, a boot-up message will be sent to the
CAN Bus.
1, 8, 9
Initialization
FALSE
(Pre-Operational)
Generates a general reset of EPOS2 software having same
effect as turning off and on the supply voltage. Not saved
parameters will be overwritten with values saved to the
EEPROM using «Save all Parameters».
Operational
TRUE
Communication:
– Service Data Objects (SDO) Protocol
– Process Data Objects (PDO) Protocol
– Emergency Objects
– Network Management (NMT) Protocol
FALSE
Communication:
– Network Management (NMT) Protocol
– Layer setting services (LSS)
– Lifeguarding (Heartbeating)
Start Remote Node 2, 5
Stop Remote Node 4, 7
Stopped
Table 6-15
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EPOS2 Positioning Controllers
EPOS2 Communication Guide
CAN Communication – NMT Slave (Commands, Transitions and States)
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CAN Communication
CANopen Application Layer
The communication object possesses the identifier (=0) and consists of two bytes. The Node ID defines
the destination of the message. If zero, the protocol addresses all NMT Slaves.
Figure 6-28
Protocol
Enter
Pre-Operational
Reset
Communication
Reset Node
CAN Communication – NMT Object
COB-ID
CS
(Byte 0)
Node ID
(Byte 1)
Functionality
0
0x80
0 (all)
All CANopen nodes (EPOS2 devices) will enter NMT State “PreOperational”.
0
0x80
n
The CANopen node (EPOS2 device) with Node ID “n” will enter
NMT State “Pre-Operational”.
0
0x82
0 (all)
All CANopen nodes (EPOS2 devices) will reset the
communication.
0
0x82
n
The CANopen node (EPOS2 device) with Node ID “n” will reset
the communication.
0
0x81
0 (all)
All CANopen nodes (EPOS2 devices) will reset.
0
0x81
n
The CANopen node (EPOS2 device) with Node ID “n” will reset.
0
0x01
0 (all)
All CANopen nodes (EPOS2 devices) will enter NMT State
“Operational”.
0
0x01
n
The CANopen node (EPOS2 device) with Node ID “n” will enter
NMT State “Operational”.
0
0x02
0 (all)
All CANopen nodes (EPOS2 devices) will enter NMT State
“Stopped”.
0
0x02
n
The CANopen node (EPOS2 device) with Node ID “n” will enter
NMT State “Stopped”.
Start Remote Node
Stop Remote Node
Table 6-16
6-40
CAN Communication – NMT Protocols
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CAN Communication
CANopen Application Layer
6.3.3.6
Node Guarding Protocol
Used to detect absent devices that do not transmit PDOs regularly (e.g. due of “bus off”). The NMT Master can manage “Node Guarding”, a database where, among other information, expected states of all
connected devices are recorded. With cyclic Node Guarding, the NMT Master regularly polls its NMT
Slaves. To detect the absence of the NMT Master, the slaves test internally, whether Node Guarding is
taking place in the defined time interval (Life Guarding).
Node Guarding is initiated by the NMT Master (in “Pre-Operational” state of the slaves) by transmitting a
Remote Frame. Node Guarding is also activated if “Stopped” state is active.
Legend: 1) Data Field / 2) Node Guard Time / 3) Node/Life Guarding Event
Figure 6-29
CAN Communication – Node Guarding Protocol (Timing Diagram)
Data Field
Holds the NMT State. Upon receipt of a node guard answer, bit 8 toggles between 0x00 and 0x80. Thus,
the data field supports the following values:
Value
Toggle
EPOS2 NMT State
0x04
not set
Stopped
0x84
set
Stopped
0x05
not set
Operational
0x85
set
Operational
0x7F
not set
Pre-Operational
0xFF
set
Pre-Operational
Table 6-17
CAN Communication – Node Guarding Protocol (Data Field)
Node Guard Time
Is calculated as follows: NodeGuardTime = GuardTime ⋅ LifeTimeFactor
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CAN Communication
CANopen Application Layer
Node / Life Guarding Event
In case EPOS2 misses the Remote Transmit Request (RTR), it will change it’s device state to “Error”
(Node Guarding Error).
In case the answer is missed by the Master System, it may react with the Node Guarding Event.
6.3.3.7
Heartbeat Protocol
The Heartbeat Protocol has a higher priority than the Node Guarding Protocol. If both are enabled, only
the Heartbeat Protocol is supported. The EPOS2 transmits a cyclic heartbeat message if the Heartbeat
Protocol is enabled (Heartbeat Producer Time 0 = Disabled / greater than 0 = enabled). The Heartbeat
Consumer guards receipt of the Heartbeat within the Heartbeat Consumer Time. If the Heartbeat Producer Time is configured in EPOS2, it will start immediately with the Heartbeat Protocol.
Legend: 1) Data Field / 2) Heartbeat Producer and Heartbeat Consumer Time / 3) Hearbeat Event
Figure 6-30
CAN Communication – Heartbeat Protocol (Timing Diagram)
Data Field
Holds the NMT State. Each time the value of toggle between 0x00 and 0x80. Therefore the following
values for the data field are possible:
Value
0x00
Bootup
0x04
Stopped
0x05
Operational
0x7F
Pre-Operational
Table 6-18
6-42
EPOS2 NMT State
CAN Communication – Heartbeat Protocol (Data Field)
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CAN Communication
Identifier Allocation Scheme
Heartbeat Producer Time and Heartbeat Consumer Time
The Heartbeat Consumer Time must be longer than the Heartbeat Producer Time because of generation, sending and indication time ( HeartbeatConsumerTime ≥ HeartbeatProducerTime + 5ms ). Each
indication of the Master resets the Heartbeat Consumer Time.
Heartbeat Event
If EPOS2 is in an unknown state (e.g. supply voltage failure), the Heartbeat Protocol cannot be sent to
the Master. The Master will recognize this event upon elapsed Heartbeat Consumer Time and will generate a Heartbeat Event.
6.4
Identifier Allocation Scheme
The default ID allocation scheme consists of a functional part (Function Code) and a Module ID, which
allows distinguishing between devices. The Module ID is assigned by DIP switches and a SDO Object.
Figure 6-31
CAN Communication – Default Identifier Allocation Scheme
This ID allocation scheme allows peer-to-peer communication between a single master device and up to
127 slave devices. It also supports broadcasting of non-confirmed NMT Services, SYNC and Node
Guarding.
The predefined master/slave connection set supports…
•
one emergency object,
•
one SDO,
•
four Receive PDOs and three Transmit PDOs and the
•
node guarding object.
Object
Function Code
(binary)
Resulting COB-ID
Communication
Parameter at
Index
NMT
0000
0
–
SYNC
0001
128
(0080h)
1005h
129…255
(0081h-00FFh)
1014h
EMERGENCY
PDO1 (tx)
0011
385…511
(0181h-01FFh)
1800h
PDO1 (rx)
0100
513…639
(0201h-027Fh)
1400h
PDO2 (tx)
0101
641…8767
(0281h-02FFh)
1801h
PDO2 (rx)
0110
769…895
(0301h-037Fh)
1401h
PDO3 (tx)
0111
897…1023
(0381h-03FFh)
1802h
PDO3 (rx)
1000
1025…1151
(0401h-047Fh)
1402h
PDO4 (tx)
1001
1153…1279
(0481h-04FFh)
1803h
PDO4 (rx)
1010
1281…1407
(0501h-057Fh)
1403h
SDO1 (tx)
1011
1409…1535
(0581h-05FFh)
1200h
SDO1 (rx)
1100
1537…1663
(0601h-067Fh)
1200h
Table 6-19
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EPOS2 Communication Guide
CAN Communication – Objects of the Default Connection Set
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CAN Communication
Identifier Allocation Scheme
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Gateway Communication (USB & RS232 to CAN)
7
Gateway Communication (USB & RS232 to CAN)
Using the gateway functionality, the master can access all other EPOS2 devices connected to the CAN
Bus via the gateway device’s USB port or RS232 interface. Even other CANopen devices (I/O modules)
supporting the CANopen standard CiA 301 may be accessed.
Figure 7-32
Gateway Communication – Structure
Communication data are exchanged between USB/RS232 master and the gateway using a maxon-specific USB/RS232 protocol.
Data between the gateway and the addressed device are exchanged using the CANopen SDO protocol
according to the CiA 301.
Step
1
Sender Receiver
Protocol
USB
[maxon-specific]
or
RS232
[maxon-specific]
Description
Command including the node ID is sent to the
device working as a gateway. The gateway decides
whether to execute the command or to translate
and forward it to the CAN Bus.
USB or RS232
Master
Criteria:
EPOS2 ID 1, Gateway Node ID = 0 (Gateway)
Node ID = DIP switch
else
Execute
Execute
Forward to CAN
2
CANopen [SDO]
EPOS2 ID 1, Gateway The gateway is forwarding the command to the
CAN network. The USB/RS232 command is
EPOS2 ID 2
translated to a CANopen SDO service.
3
CANopen [SDO]
EPOS2 ID 2
The EPOS2 ID 2 is executing the command and
sending the corresponding CAN frame back to the
EPOS2 ID 1, Gateway gateway.
4
USB
[maxon-specific]
or
RS232
[maxon-specific]
The gateway is receiving the CAN frame
EPOS2 ID 1, Gateway
corresponding to the SDO service. This CAN frame
is translated back to the USB/RS232 frame and
USB or RS232 Master
sent back to the USB/RS232 master.
Table 7-20
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Gateway Communication – Data Exchange
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Gateway Communication (USB & RS232 to CAN)
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Error Code Definition
CANopen-specific Error Codes
8
Error Code Definition
8.1
CANopen-specific Error Codes
Following error codes are defined by CANopen CiA 301 Communication Profile for Industrial Systems:
Error Code
Name
Cause
0x0000 0000
No Communication Error
RS232 communication successful
0x0503 0000
Toggle Error
Toggle bit not alternated
0x0504 0000
SDO Time Out
SDO protocol timed out
0x0504 0001
Client / Server Specifier Error
Client / server command specifier not valid or
unknown
0x0504 0004
CRC Error
CRC
0x0504 0005
Out of Memory Error
Out of memory
0x0601 0000
Access Error
Unsupported access to an object
0x0601 0001
Write Only Error
Read command to a write only object
0x0601 0002
Read Only Error
Write command to a read only object
0x0602 0000
Object does not exist Error
Object does not exist in Object Directory. Last
read or write command had wrong object
Index or SubIndex
0x0604 0041
PDO mapping Error
Object cannot be mapped to the PDO
0x0604 0042
PDO Length Error
Number and length of objects to be mapped
would exceed PDO length
0x0604 0043
General Parameter Error
General parameter incompatibility
0x0604 0047
General internal Incompatibility Error
General internal incompatibility in device
0x0606 0000
Hardware Error
Access failed due to hardware error
0x0607 0010
Service Parameter Error
Data type does not match, length or service
parameter does not match
0x0607 0012
Service Parameter too long Error
Data type does not match, length of service
parameter too high
0x0607 0013
Service Parameter too short Error
Data type does not match, length of service
parameter too low
0x0609 0011
Object SubIndex Error
Last read or write command had wrong object
SubIndex
0x0609 0030
Value Range Error
Value range of parameter exceeded
0x0609 0031
Value too high Error
Value of parameter written too high
0x0609 0032
Value too low Error
Value of parameter written too low
0x0609 0036
Maximum less Minimum Error
Maximum value is less than minimum value
0x0800 0000
General Error
General error
0x0800 0020
Transfer or Store Error
Data cannot be transferred or stored
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Error Code Definition
maxon-specific Error Codes
Error Code
Name
Cause
0x0800 0021
Local Control Error
Data cannot be transferred or stored to
application because of local control
0x0800 0022
Wrong Device State
Data cannot be transferred or stored to
application because of present device state
Table 8-21
8.2
Communication Errors – CANopen-specific Error Codes
maxon-specific Error Codes
Following error codes are specific to maxon’s EPOS2 devices:
Error Code
Cause
0x0F00 FFC0 Wrong NMT State Error
Device is in wrong NMT state
0x0F00 FFBF Illegal Command Error
RS232 command is illegal (does not exist)
0x0F00 FFBE Password Error
Password is incorrect
0x0F00 FFBC Service Mode Error
Device is not in service mode
0x0F00 FFB9
Wrong CAN ID
Table 8-22
8-48
Name
CAN ID Error
Communication Errors – maxon-specific Error Codes
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LIST OF FIGURES
Figure 2-1
Documentation Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Figure 4-2
USB Communication – Command Sequence. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Figure 4-3
USB Communication – Sending a Data Frame to EPOS2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Figure 4-4
USB Communication – Receiving a Response Data Frame from EPOS2 . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Figure 4-5
USB Communication – Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Figure 4-6
USB Communication – CRC Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Figure 4-7
USB Communication – Slave State Machine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Figure 5-8
RS232 Communication – Command Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Figure 5-9
RS232 Communication – Sending a Data Frame to EPOS2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Figure 5-10
RS232 Communication – Receiving a Response Data Frame from EPOS2 . . . . . . . . . . . . . . . . . . . . . . . . .22
Figure 5-11
RS232 Communication – Frame Structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Figure 5-12
RS232 Communication – CRC-CCITT Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Figure 5-13
RS232 Communication – Slave State Machine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Figure 6-14
CAN Communication – Protocol Layer Interactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Figure 6-15
CAN Communication – ISO 11898 Basic Network Setup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Figure 6-16
CAN Communication – CAN Data Frame. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Figure 6-17
CAN Communication – Standard Frame Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Figure 6-18
CAN Communication – Process Data Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Figure 6-19
CAN Communication – PDO Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
Figure 6-20
CAN Communication – PDO Communication Modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
Figure 6-21
CAN Communication – Service Data Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Figure 6-22
CAN Communication – Object Dictionary Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Figure 6-23
CAN Communication – Synchronization Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
Figure 6-24
CAN Communication – Synchronous PDO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
Figure 6-25
CAN Communication – Emergency Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Figure 6-26
CAN Communication – Network Management (NMT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Figure 6-27
CAN Communication – NMT Slave State Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
Figure 6-28
CAN Communication – NMT Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
Figure 6-29
CAN Communication – Node Guarding Protocol (Timing Diagram). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
Figure 6-30
CAN Communication – Heartbeat Protocol (Timing Diagram) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
Figure 6-31
CAN Communication – Default Identifier Allocation Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
Figure 7-32
Gateway Communication – Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
Document ID: rel5984
Edition: May 2016
© 2016 maxon motor. Subject to change without prior notice.
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LIST OF TABLES
Table 1-1
Notations used in this Document . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Table 1-2
Sources for additional Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Table 4-3
USB Communication – Timeout Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Table 4-4
ReadObject “Home Offset”. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Table 4-5
Answer to ReadObject “Home Offset” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Table 5-6
RS232 Communication – Timeout Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Table 5-7
ReadObject “Software Version” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Table 5-8
Answer to ReadObject “Software Version”. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Table 6-9
CAN Communication – Notations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Table 6-10
CAN Communication – Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Table 6-11
CAN Communication – Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Table 6-12
CAN Communication – Object Dictionary Layout. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Table 6-13
CAN Communication – Object Dictionary Entry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Table 6-14
CAN Communication – Communication Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Table 6-15
CAN Communication – NMT Slave (Commands, Transitions and States) . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Table 6-16
CAN Communication – NMT Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Table 6-17
CAN Communication – Node Guarding Protocol (Data Field) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Table 6-18
CAN Communication – Heartbeat Protocol (Data Field) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Table 6-19
CAN Communication – Objects of the Default Connection Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Table 7-20
Gateway Communication – Data Exchange. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Table 8-21
Communication Errors – CANopen-specific Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Table 8-22
Communication Errors – maxon-specific Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
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Document ID: rel5984
Edition: May 2016
© 2016 maxon motor. Subject to change without prior notice.
maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
INDEX
A
I
Access Error 47
access to CAN bus via USB or RS232 45
applicable EU directive 2
ID (definition) 29
Illegal Command Error 48
incorporation into surrounding system 2
InitiateSegmentedRead (function) 9
InitiateSegmentedWrite (function) 11
intended purpose 7
C
CAN
commands 13
communication 29
error codes 47
CAN (definition) 29
CAN Client (definition) 30
CAN Master (definition) 30
CAN Server (definition) 30
CAN Slave (definition) 30
Client / Server Specifier Error 47
CMS (definition) 29
COB (definition) 29
COB-ID (definition) 29
codes (used in this document) 5
communication via gateway 45
L
Life Guarding 41
Local Control Error 48
M
MAC (definition) 29
Maximum less Minimum Error 47
N
NMT State
Heartbeat 42
Node Guarding 41
No Communication Error 47
Node Guard Time, calculation of 41
Node Guarding 41
non-compliance of surrounding system 2
notations (used in this document) 5
E
EDS (definition) 29
Error CAN ID 48
error codes 47
Error Service Mode 48
EU directive, applicable 2
O
Object (definition) 30
Object does not exist Error 47
Object SubIndex Error 47
OD (definition) 29
operating license 2
OSI Reference Model 31
other machinery (incorporation into) 2
Out of Memory Error 47
F
functions
read 9
write 10
G
General Error 47
General internal Incompatibility Error 47
General Parameter Error 47
P
H
Hardware Error 47
Heartbeat Consumer Time, calculation of 43
how to
read this document 2
maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
Password Error 48
PDO (definition) 29
PDO Length Error 47
PDO mapping Error 47
PLC (definition) 29
prerequisites prior installation 2
purpose
of the device 7
of this document 5
Document ID: rel5984
Edition: May 2016
© 2016 maxon motor. Subject to change without prior notice.
Z-51
R
ReadLSSFrame (function) 14
ReadObject (function) 9
Receive (definition) 30
RequestCANFrame (function) 13
RO (definition) 29
RS232
command reference 9
communication 21
to CAN Gateway 45
RW (definition) 29
S
SDO (definition) 29
SDO Time Out 47
SegmentedWrite (function) 11
SegmentRead (function) 10
SendCANFrame (function) 13
SendLSSFrame (function) 14
SendNMTService (function) 12
Service Parameter Error 47
Service Parameter too long Error 47
Service Parameter too short Error 47
surrounding system (incorporation into) 2
T
Toggle Error 47
Transfer or store Error 47
Transmit (definition) 30
U
USB
command reference 9
communication 15
to CAN Gateway 45
V
Value Range Error 47
Value too high Error 47
Value too low Error 47
W
WO (definition) 29
Write Only 47
WriteObject (function) 10
Wrong Device State 48
Wrong NMT State Error 48
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Document ID: rel5984
Edition: May 2016
© 2016 maxon motor. Subject to change without prior notice.
maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
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maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
Document ID: rel5984
Edition: May 2016
© 2016 maxon motor. Subject to change without prior notice.
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© 2016 maxon motor. All rights reserved.
The present document – including all parts thereof – is protected by copyright. Any use (including reproduction, translation,
microfilming and other means of electronic data processing) beyond the narrow restrictions of the copyright law without the
prior approval of maxon motor ag, is not permitted and subject to persecution under the applicable law.
maxon motor ag
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Phone +41 41 666 15 00
Fax +41 41 666 16 50
www.maxonmotor.com
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Document ID: rel5984
Edition: May 2016
© 2016 maxon motor. Subject to change without prior notice.
maxon motor control
EPOS2 Positioning Controllers
EPOS2 Communication Guide
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