Xircom An Intel GEM3501 Core Engine, PCS-1900 GSM Radio Module User Manual Core Engine Developer Guide

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Date Submitted	2001-08-31 00:00:00
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Core Engine
GSM/GPRS Wireless Terminal
Developer Guide
(Preliminary Draft – 7/6/2001)
Confidential
© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
Part Number: 07100026, Revision: 002
Confidential
1 REVISION HISTORY
Date
Revision
Description
3/20/01
001
Initial revision (preliminary).
7/6/01
002
Added Core Engine RF antenna connector information.
Added information on antenna design considerations.
Added Core Engine 60-pin I/O connector pin-out information.
Updated Carrier Board section for Rev B carrier board.
Updated information in Detailed Specifications section.
Removed reference to dual-band 900/1800 version.
Added the following new sections:
Power (requirements; management; etc.).
Serial communications (single vs dual ports, XGAP, etc.).
Audio (mic & speaker interface; audio path selection;
cabling; etc.).
Updating the Core Engine firmware.
© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
Part Number: 07100026, Revision: 002
Confidential
2 SAFETY PRECAUTIONS
2.1 Important Safety Information
Some of the following information may not apply to all devices described in this manual.
However, precautions should be observed when handling any electrical device.
Save this manual, it contains important safety information and operating instructions.
Do not expose the Core Engine product to open flames.
Care should be taken so that liquids do not spill into the devices.
A qualified electrician should perform all primary connections to AC power.
Do not attempt to disassemble the product. Doing so will void the warranty. With the
exception of Subscriber Identification Modules (SIM), this product does not contain
consumer serviceable components.
2.2 Guidelines for Limiting RF Exposure
The Core Engine products are GSM radio transceivers.
The following installation and operation restrictions apply to the all Core Engine products:
A separation distance of at least 20 cm (7 7/8) inches between the antenna and body of
the user and other persons must be maintained at all times
In FIXED applications using a 1900Mhz Core Engine antenna gain* is limited to a
maximum of 7 dBi, with a corresponding equivalent isotropic radiated power (EIRP) of 37
dBm / 5 W
In MOBILE applications using a 1900Mhz Core Engine antenna gain* is limited to a
maximum of 3 dBi, with a corresponding equivalent isotropic radiated power (EIRP) of 33
dBm / 3 W
Desktop and other uses of these devices where the antenna can easily be relocated are
considered by the FCC to be mobile applications.
* Antenna gain is defined as gain in dBi (dB referenced to an isotropic radiator) minus cabling loss.
NOTE: Additional care must be taken by the installer and/or user of the Core Engine
products to ensure proper antenna selection and installation. Adherence to the
above conditions is necessary to comply with FCC requirements for safe operation
regarding exposure to RF radiation.
2.3 Disclaimer
The information and instructions contained within this publication comply with all
FCC, NRLT, IMEI and other applicable codes in effect at the time of publication.
Xircom, Inc. disclaims all responsibility for any act, or breach of law, code or
regulation, including local or state codes, performed by a third party.
© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
Part Number: 07100026, Revision: 002
Confidential
Xircom, Inc., an Intel company (hereafter “Xircom”) strongly recommends that all
installations, hookups, transmissions, etc. be performed by persons who are
experienced in the fields of radio frequency technologies. Xircom acknowledges that
the installation, setup and transmission guidelines contained within this publication
are guidelines, and that each installation may have variables outside of the
guidelines contained herein. Said variables must be taken into consideration when
installing or using the product, and Xircom, Inc. shall not be responsible for
installations or transmissions that fall outside of the parameters set forth in this
publication.
Xircom shall not be liable for consequential or incidental damages, injury to any
person or property, anticipated or lost profits, loss of time, or other losses incurred
by Customer or any third party in connection with the installation of the Products or
Customer's failure to comply with the information and instructions contained herein.
2.4 Beta Release Notes
The information in this document is preliminary and subject to change by Xircom.
2.4.1 Data Services
The current software release does not support USSD or Group 3 Fax. These services will
be added in subsequent versions.
2.4.2 AT Commands
The current software version may not support all AT commands listed in this document.
Please reference the Core Engine Programmer Reference document for details of the
software AT command implementation.
2.4.3 PUK Procedure
The PUK procedure outlined in this document will be changing.
© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
Part Number: 07100026, Revision: 002
Confidential
TABLE OF CONTENTS
1 REVISION HISTORY .................................................................................................... 2
2 SAFETY PRECAUTIONS ............................................................................................. 3
2.1 Important Safety Information........................................................................................ 3
2.2 Guidelines for Limiting RF Exposure............................................................................ 3
2.3 Disclaimer.................................................................................................................... 3
2.4 Beta Release Notes..................................................................................................... 4
2.4.1 Data Services....................................................................................................... 4
2.4.2 AT Commands ..................................................................................................... 4
2.4.3 PUK Procedure .................................................................................................... 4
3 PRODUCT OVERVIEW ................................................................................................ 9
3.1 GSM Overview ............................................................................................................ 9
3.2 Model Variation............................................................................................................ 9
3.3 General Description ..................................................................................................... 9
3.4 Summary of the Features for the Core Engine modem ...............................................10
3.5 Programmer Reference ..............................................................................................10
3.6 Backward Compatibility...............................................................................................10
3.7 Modes of Operation ....................................................................................................11
3.7.1 Circuit Switched Data ..........................................................................................11
3.7.2 Transparent and Non Transparent Transmissions...............................................11
3.7.3 Short Message Service .......................................................................................11
3.7.4 Voice...................................................................................................................12
3.7.5 General Packet Radio Service (GPRS) ...............................................................12
4 CARRIER BOARD...................................................................................................... 13
4.1 Core Engine Modem I/O Interface [P4] .......................................................................13
4.2 Core Engine I/O Signal Header [J4] ............................................................................17
4.3 Ground Points [J2, J9] ................................................................................................17
4.4 RF Antenna Connector [J5, J6]...................................................................................17
4.5 Power [J7, J8, J10] ....................................................................................................17
4.6 Primary Serial Interface [P3] .......................................................................................18
© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
Part Number: 07100026, Revision: 002
Confidential
4.7 Secondary Serial Interface [P2] ..................................................................................18
4.8 Primary Audio Interface [P1] .......................................................................................19
4.9 Secondary Audio Interface [J1] ...................................................................................20
4.10 Audio Interface Select [JP2]......................................................................................20
4.11 Subscriber Interface Module [J3] ..............................................................................20
4.12 Status Indication [DS1] .............................................................................................20
5 POWER....................................................................................................................... 22
5.1 Power Up Sequence...................................................................................................22
5.2 Power Management....................................................................................................22
5.2.1 Power Modes ......................................................................................................22
5.2.2 Hardware Signals................................................................................................24
5.2.3 Software Commands...........................................................................................24
5.3 Transmit Power ..........................................................................................................25
6 SERIAL COMMUNICATIONS .................................................................................... 26
6.1 Supported Serial Port Configurations..........................................................................26
6.1.1 Single Port Configuration ....................................................................................26
6.1.2 Dual Port Configuration .......................................................................................27
7 AUDIO......................................................................................................................... 29
7.1 Audio Path Selection ..................................................................................................29
7.1.1 Hardware Selection of Audio Path.......................................................................29
7.1.2 Software Selection of Audio Path ........................................................................29
7.2 Microphone Input ........................................................................................................29
7.3 Speaker Output ..........................................................................................................30
7.4 Audio Circuit Implementation ......................................................................................31
7.4.1 Example Single-Ended Microphone Circuit .........................................................31
7.4.2 Example Differential Microphone Circuit..............................................................32
7.5 Microphone Cable Considerations ..............................................................................32
8 RF ANTENNA............................................................................................................. 33
8.1 Antenna Connector.....................................................................................................33
8.2 Antenna Selection.......................................................................................................33
8.3 Antenna Performance Guidelines ...............................................................................33
8.3.1 Antenna Impedance Match .................................................................................33
8.3.2 Antenna Pattern and Gain...................................................................................34
8.3.3 Antenna Beam Width ..........................................................................................34
© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
Part Number: 07100026, Revision: 002
Confidential
8.3.4 Antenna Polarization ...........................................................................................35
8.4 Antenna Location and Network Communication .........................................................35
9 PROVISIONING THE SIM .......................................................................................... 36
9.1 GSM Services Supported by the Core Engine modem................................................36
9.2 Selecting the Modes of Operation...............................................................................36
10 INSTALLATION & INITIALIZATION......................................................................... 37
10.1 Installation and Verification .......................................................................................37
10.1.1 Installation.........................................................................................................37
10.1.2 Verification ........................................................................................................38
10.2 SMS Message Verification........................................................................................41
10.2.1 Modem Sent SMS (Text)...................................................................................41
10.2.2 Modem RECEIVE SMS (Text)...........................................................................44
10.2.3 SIM Data Provisioning Verification (Optional) ....................................................44
10.2.4 Match Modem Serial port to CPE ......................................................................44
10.2.5 Verify Setup ......................................................................................................44
10.2.6 Connect Primary Serial Port Cable....................................................................44
10.3 Final Verification .......................................................................................................45
10.3.1 SMS Verification................................................................................................45
11 DETAILED SPECIFICATIONS ................................................................................. 46
11.1 Physical Dimensions and Weight..............................................................................46
11.2 Operating Power.......................................................................................................46
11.2.1 Transmit Power .................................................................................................46
11.2.2 Receiver Sensitivity...........................................................................................47
11.3 Care and Maintenance..............................................................................................47
12 ENVIRONMENTAL SPECIFICATIONS .................................................................... 48
12.1 Climatic.....................................................................................................................48
12.1.1 Climatic: Operational .........................................................................................48
12.1.2 Climatic: Storage and Transportation ................................................................48
12.2 Mechanical ...............................................................................................................48
12.2.1 Mechanical: Operational....................................................................................48
12.2.2 Mechanical: Storage and Transportation ...........................................................48
12.2.3 Mechanical: Proposed Standards......................................................................49
12.3 Electromagnetic ........................................................................................................49
12.3.1 Electromagnetic Emissions ...............................................................................49
12.3.2 Electromagnetic Immunity .................................................................................49
13 GLOSSARY AND ACRONYMS ............................................................................... 50
© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
Part Number: 07100026, Revision: 002
Confidential
14 UPDATING THE CORE ENGINE FIRMWARE......................................................... 53
14.1 Required Files ..........................................................................................................53
14.2 Download Utility ........................................................................................................53
14.3 Download Procedure ................................................................................................54
15 INSTALLING A REMOTE ANTENNA ...................................................................... 56
15.1 Antenna Coaxial Cable and Connectors ...................................................................56
15.2 Outdoor Antenna Grounding .....................................................................................56
15.3 Coaxial Cable Routing ..............................................................................................56
15.4 Coaxial Cable Losses and Lengths...........................................................................57
15.5 Formula Examples....................................................................................................59
15.5.1 Example 1: ........................................................................................................59
15.5.2 Example 2: ........................................................................................................59
15.5.3 Example 3: ........................................................................................................59
© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
Part Number: 07100026, Revision: 002
Confidential
3 PRODUCT OVERVIEW
The Core Engine modem is a compact, wireless modem that utilizes the international
standard Global System for Mobile communications (GSM). The device enables low-cost,
application-specific, two-way communication and control. It takes full advantage of GSM
capabilities such as Subscriber Identity Modules (SIM), which are "smart cards" that
provides numerous advantages.
Over-the-air communication lets the Core Engine accomplish tasks that previously
required on-site visits and offers innovative new service capabilities never before
available. In addition, terminal authentication and data encryption ensures a more
confidential communication link between the terminal user and the data recipient.
3.1 GSM Overview
The GSM communications standard, already widely deployed in Europe, Asia, and North
America, overcomes many of the drawbacks found in other wireless telemetry
approaches. The GSM communications network was designed from the ground up, for
reliable and inexpensive digital data transfers.
The GSM network employs integrated data and data-friendly capabilities such as short
message services, circuit switched data and, soon, GPRS, which brings the best of
wireless and packet data into harmony and will make new services even more practical
and affordable. In many countries around the world, especially in Western Europe, GSMbased networks are the only digital networks deployed.
The Core Engine modem leverages existing public GSM networks, as opposed to other
systems that require the utility to build, operate, and maintain expensive private wireless
networks.
3.2 Model Variation
The Core Engine modem supports GSM Short message service (SMS), voice, and circuit
switched data (transparent and non-transparent mode) up to 9.6 Kbps. This modem also
is GPRS hardware ready. It provides GPRS packet data up to and including Class 10, in
addition to Short Message Service (SMS), voice, and circuit switched data (transparent
and non-transparent mode) up to 9.6 Kbps.
Core Engine modems are available in the following configuration:
1900 MHz:
Part # 4200-1100
3.3 General Description
The Core Engine Carrier Board assembly provides DC to DC conversion and standard
interface connections with drivers for two serial interfaces, a voice interface, and DC
power.
The modem operates under a wide range of DC input power. Communication is through
an RS-232 physical interface, using the GSM - AT command set.
© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
Part Number: 07100026, Revision: 002
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3.4 Summary of the Features for the Core Engine modem
Interface
Power
Radio Features
Regulatory
GSM
Functionality
GPRS
Functionality
Primary serial port
V.24 protocol, 3V levels.
Secondary serial port
Secondary 3V serial port (currently restricted to debug use).
Voice
Supports two (2) vocoder modes: full-rate, and enhanced full-rate
(EFR).
Antenna
On-board microminiature coaxial connector for RF antenna.
Command protocol
AT command set.
Subscriber Identification Module
(SIM)
3V mini-SIM carrier and interface on carrier board.
Electrical power
Fixed DC voltage 3.7V +/-0.3V
Peak currents and average power
dissipation
Refer to the Operating Power table in the Technical Specifications
section for peak currents and average power dissipation for various
modes of operation.
Frequency bands
PCS 1900 capability.
GSM features supported
Provides for all GSM authentication, encryption, and frequency
hopping algorithms.
Agency approvals
GSM Type Approval – planned
FCC Certification (Part 24) – planned
CE (European Community Certification) – planned
IC (Industry Canada) – planned
Mobile-originated and mobile-terminated SMS messages: up to 140 bytes or up to 160 GSM 7-bit
ASCII characters.
Reception of Cell Broadcast Message.
SMS Receipt acknowledgement.
Circuit Switched Data (Transparent & Non-transparent programmable from 4.8 to 9.6 Kbps).
Voice.
Supports GSM Phase 2+.
GPRS software will be available at a later date.
Table 1: Core Engine Summary of Features
3.5 Programmer Reference
For greater flexibility that enhances the usability of the Core Engine modems, Xircom
provides a Core Engine Programmer Reference. This document goes into greater detail,
in an easy to read format, on the enhanced programming capabilities specific to the Core
Engine modem, including details of supported AT commands.
3.6 Backward Compatibility
GSM functionality is forever evolving. Subsequently, in order to maintain the highest
standards, the Core Engine modems will be backward compatible with new GSM
functionality such as General Packet Radio Service (GPRS). Applications supported with
© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
Part Number: 07100026, Revision: 002
11
Confidential
early current versions of the modem will continue to be supported, as GSM technology
evolves to GPRS, and then on to third generation technologies, which are now in the
process of standardization and development.
3.7 Modes of Operation
Core Engine offers several modes of operation to address a variety of application
requirements.
3.7.1 Circuit Switched Data
Circuit switched data is the most widespread and traditional means of data and voice
transmission available today. A circuit switched connection occupies one network line for
the entire length of data transmission and during this time, no other user may access this
network line. A circuit switched connection is the optimal means for transmitting any
continuous amount of data, such as video transmission or voice.
A common example of a circuit switched network is the public telephone system. When
person A picks up the telephone and dials the number of person B, the network
determines and assigns a path for that transmission. The signal travels through each
assigned circuit switch to complete the connection.
Once the signal has reached person B, a continuous two-way transmission path has been
established. On a long distance call, for example, many circuits would need to be
connected together to make the call possible. These circuits are dedicated to the call for
the duration of the transmission and cannot be shared by other users. This requires
substantial network resources to be allocated per user.
3.7.2 Transparent and Non Transparent Transmissions
GSM provides two connection modes of transmission: transparent and non-transparent.
All Core Engine models support both modes. The transparent data mode delivers a
service with a variable error rate, with a guaranteed throughput and delay, whereas the
non-transparent mode delivers a constantly low forward error correction rate, but with a
non-guaranteed throughput or delay.
Not all networks support transparent services.
The non-transparent service delivers the most reliable performance and is closest to using
a modem over a fixed telephone line.
3.7.3 Short Message Service
To accommodate smaller messages, GSM uses short message service (SMS) for efficient
and timely data transmission and data retrieval. SMS is a point-to-point, storage and
forwarding, message service that is used in data transmissions such as paging,
notification, news flashes, and information retrieval.
Short messages can carry up to 140 8-bit characters. (160, 7-bit characters available –
refer to the Core Engine Programmer Reference for configuration)
Short Messages can be sent and received simultaneously with a voice or data call and
are sent above the voice or data in the overhead-signaling path (Traffic & Bearer).
Although similar in concept to traditional paging, the primary difference is that SMS is not
geographically restricted as paging systems are. Moreover, the GSM network stores and
resends the message if the receiver’s handset is turned off (In some cases, if a pager is
turned off, the message is simply lost).
© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
Part Number: 07100026, Revision: 002
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Confidential
Listed below are the essential characteristics and assumptions regarding the form of SMS
supported by the Core Engine modem.
Support of both mobile originated and mobile terminated SMS.
8-bit data in PDU mode
Message Class 1
Up to 140 ASCII characters per message using 8-bit data mode. (160 characters if
7bit GSM ASCII used)
Notify the network when it has memory capacity available to receive one or more
SMS messages after it has previously rejected a message because its memory
capacity was exceeded
3.7.4 Voice
The Core Engine modem has full voice capabilities, provided the necessary connections
have been made for the speaker and microphone pins on the 60-pin I/O connector. The
AT commands and their responses allow the user to enter and receive information from
the Core Engine modem. These functions include the ability for dialing, for providing onhook or off-hook, and for controlling other aspects of the voice call interface.
The Core Engine modem supports two (2) vocoder compression algorithms for voice
communication: full-rate and enhanced full-rate (EFR)
3.7.5 General Packet Radio Service (GPRS)
GPRS is the next step in GSM data services: a fully packet-based protocol service with
direct access to the Internet. By bringing the best features of messaging, circuit-switched
services, and packet data into harmony, GPRS promises to make new applications even
more practical and affordable. Future releases of the Core Engine modem will support
GPRS mode. Currently, the Core Engine modem is hardware-ready for GPRS.
© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
Part Number: 07100026, Revision: 002
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4 CARRIER BOARD
[J4] Header access to
Core Engine I/O pins.
[JP2] Audio port select jumper.
[J5] Connector
for cable to
Core Engine
RF antenna
connector.
[J1] Secondary
audio port (singleended).
[P1] RJ-9 for
primary audio port
(differential).
[J6] SMA RF
antenna
connector.
[P4] Core Engine
I/O connector.
[P2] DB-9 for
secondary
serial port.
[J7, J8, J10]
Power
3.7V (+/-0.3V).
[P3] DB-9
for primary
serial port.
[J3] SIM holder.
[J2, J9] GND ref points.
[DS1] Status LED.
Figure 1: Core Engine Carrier Board (Rev B)
NOTE: The carrier board is intended for development only, and is not suitable for
performing RF qualification.
4.1 Core Engine Modem I/O Interface [P4]
The Core Engine modem connects to the carrier board using a 60-pin connector
(connector P4 on the carrier board). The I/O interface signals are described in Table 2.
Pin
Signal
Name
I/O
Functionality
Parameters
VCC
•
0.5A per contact maximum
current per contact.
•
Vin= 3.7 +/- 0.3 Volt
VCC
•
0.5A per contact maximum
current per contact.
•
Vin= 3.7 +/- 0.3 Volt
© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
Part Number: 07100026, Revision: 002
Pin
Signal
Name
I/O
Functionality
Parameters
VCC
•
0.5A per contact maximum
current per contact.
•
Vin= 3.7 +/- 0.3 Volt
VCC
•
0.5A per contact maximum
current per contact.
•
Vin= 3.7 +/- 0.3 Volt
VCC
•
0.5A per contact maximum
current per contact.
•
Vin= 3.7 +/- 0.3 Volt
VCC
•
0.5A per contact maximum
current per contact.
•
Vin= 3.7 +/- 0.3 Volt
GND
•
(0V)
GND
•
(0V)
SPK_N1
10
BATT_LOW
11
GND
12
CTS_2
13
14
SPK_P1
GPIO0
IO
15
GND
16
RTS_2
17
18
VMIC
RESET_B
19
GND
20
RINGER
21
MIC_N1
14
Confidential
•
Differential output
•
Differential output voltage typ. 3.7V
•
Speaker 1 (primary)
•
Output differential max. DC offset 100mV
•
Differential output load resistance min. 15 Ohm
•
Output load capacitance max. 4700pF
•
Vol min = 0V
Vol max = 0.2V
•
Voh min = 2.28V
Voh max = 2.53V
•
(0V)
•
Active low when BATT
voltage is <= 3.4V
•
Flow control
•
Vol min = 0V
Vol max = 0.2V
•
2nd port (DCE)
•
Voh min = 2.28V
Voh max = 2.53V
•
Clear to Send
•
Differential output
•
Differential output voltage typ. 3.7V
•
Speaker 1 (primary)
•
Output differential max. DC offset 100mV
•
Differential output load resistance min. 15 Ohm
•
Output load capacitance max. 4700pF
•
Vil min = -0.3V
Vil max = 0.496V
•
Vih min = 1.771V
Vih max = 3.3V
•
Vol min = 0V
Vol max = 0.2V
•
Voh min = 2.28V
Vol max = 2.53V
•
(0V)
•
GPIO
•
Flow control.
•
Vol min = 0V
Vol max = 0.2V
•
2nd port (DCE)
•
Voh min = 2.28V
Voh max = 2.53V
•
Request to Send
•
Bias voltage output for Mic(s)
•
Vmic Typ = 1.8V, min. = 1.6V
•
Current 2mA
•
Reset Baseband
•
Vil min = -0.3V
Vil max = 0.496V
•
Active Low
•
Vih min = 1.771V
Vih max = 3.3V
•
(0V)
•
Vol min = 0V
Vol max = 0.2V
•
Voh min = 2.28V
Voh max = 2.53V
•
External ringer function
•
Differential input
•
Input voltage differential 1.03Vpp
•
MIC 1 (primary)
•
Differential input resistance typ. 50Kohm
© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
Part Number: 07100026, Revision: 002
Pin
22
Signal
Name
PWR_DWN
I/O
Functionality
•
Active low input bring the unit
down like CPWROFF
Parameters
•
Input capacitance typ. 5pF
•
Vil min = -0.3V
Vil max = 0.496V
•
Vih min = 1.771V
Vih max = 3.3V
23
GND
•
(0V)
24
GND
•
(0V)
25
MIC_P1
26
TXON
27
GND
28
GPIO1
IO
29
30
31
32
RX_2
AUDIO_EN
TX_2
SLEEP
•
Differential input
•
Input voltage differential 1.03 Vpp
•
MIC 1 (primary)
•
Differential input resistance typ. 50Kohm
•
Input capacitance typ. 5pF
•
Transmitter on
•
Vol min = 0V
Vol max = 0.2V
•
Active High
•
Voh min = 2.28V
Voh max = 2.53V
•
GPIO
•
Vil min = -0.3V
Vil max = 0.496V
•
Vih min = 1.771V
Vih max = 3.3V
•
Vol min = 0V
Vol max = 0.2V
•
Voh min = 2.28V
Vol max = 2.53V
•
Check your Rx/Tx direction
•
Vol min = 0V
Vol max = 0.2V
•
Core Engine is DCE
•
Voh min = 2.28V
Voh max = 2.53V
•
Active high when audio circuit
should be enabled
•
Vol min = 0V
Vol max = 0.2V
•
Voh min = 2.28V
Voh max = 2.53V
•
Can be used by a customer
to go into power savings
mode on their audio circuit.
•
Check your Rx/Tx direction
•
Vil min = -0.3V
Vil max = 0.496V
•
Core is DCE
•
Vih min = 1.771V
Vih max = 3.3V
•
Indication when RF section is
asleep
•
Vol min = 0V
Vol max = 0.2V
•
Voh min = 2.28V
Voh max = 2.53V
•
(0V)
•
Vil min = -0.3V
Vil max = 0.496V
•
Vih min = 1.771V
Vih max = 3.3V
•
33
GND
34
AUDIO_SEL
35
36
37
38
LED0_RMT
SPK_N2
LED1_RMT
SPK_P2
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•
Active Low
Selection between
Primary/Secondary audio
port
•
Active low
•
High=Primary,
Low=Secondary
•
Used for driving LED (Red)
•
Vol min = 0V
Vol max = 0.2V
•
Active High
•
Voh min = 2.28V
Voh max = 2.53V
•
Differential output
•
Differential output voltage typ. 3.7V
•
Speaker 2 (secondary)
•
Output differential max. DC offset 100mV
•
Differential output load resistance min. 15 Ohm
•
Output load capacitance max. 4700pF.
•
Used for driving LED (Green)
•
Vol min = 0V
Vol max = 0.2V
•
Active High
•
Voh min = 2.28V
Voh max = 2.53V
•
Differential output
•
Differential output voltage typ. 3.7V
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Pin
39
40
Signal
Name
WAKE_UP
MIC_N2
I/O
41
GND
42
MIC_P2
43
RX_1
44
GND
45
DSR_1
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Functionality
Parameters
•
•
Output differential max. DC offset 100mV
•
Differential output load resistance min. 15 Ohm
•
Output load capacitance max. 4700pF.
•
Vil min = -0.3V
Vil max = 0.496V
•
Vih min = 1.771V
Vih max = 3.3V
Speaker 2 (secondary)
•
Wake up request if baseband
is asleep
•
Active Low
•
Differential input
•
Input voltage differential 1.03Vpp
•
MIC 2 (secondary)
•
Differential input resistance typ. 50Kohm
•
Input capacitance typ. 5pF
•
(0V)
•
Differential input
•
Input voltage differential 1.03 Vpp
•
MIC 2 (secondary)
•
Differential input resistance typ. 50Kohm
•
Input capacitance typ. 5pF
•
Check your Rx/Tx direction
•
Vol min = 0V
Vol max = 0.2V
•
1st port
•
Voh min = 2.28V
Voh max = 2.53V
•
Core is DCE
•
(0V)
•
Core is DCE
•
Vol min = 0V
Vol max = 0.2V
•
Data Set Ready (DSR)
•
Voh min = 2.28V
Voh max = 2.53V
46
TBAT
•
Thermistor voltage divider
input (NTC)
•
T.B.D.
47
DCD_1
•
Core is DCE
•
Vol min = 0V
Vol max = 0.2V
•
Data Carrier Detect (DCD)
•
Voh min = 2.28V
Voh max = 2.53V
48
SIM_CLK
•
SIM
•
T.B.D.
49
RI_1
•
Core is DCE
•
Vol min = 0V
Vol max = 0.2V
•
Ring Indicator (RI)
•
Voh min = 2.28V
Voh max = 2.53V
•
Indicates incoming circuit
switched data or voice call.
•
(0V)
50
GND
51
TX_1
•
Check your Rx/Tx direction
•
Vil min = -0.3V
Vil max = 0.496V
•
1st port
•
Vih min = 1.771V
Vih max = 3.3V
•
Core is DCE
52
SIM_IO
IO
•
SIM
•
T.B.D.
53
RTS_1
•
Flow control
•
Vil min = -0.3V
Vil max = 0.496V
•
1st port (DCE)
•
Vih min = 1.771V
Vih max = 3.3V
•
Request To Send (RTS)
54
SIM_RST
•
SIM
•
T.B.D.
55
CTS_1
•
Flow control
•
Vol min = 0V
Vol max = 0.2V
•
1st port (DCE)
•
Voh min = 2.28V
Voh max = 2.53V
•
Clear To Send (CTS)
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Pin
Signal
Name
I/O
Functionality
Parameters
56
SIM_GND
•
SIM
•
GND
57
DTR_1
•
Core is DCE
•
Vil min = -0.3V
Vil max = 0.496V
•
Data Terminal Ready (DTR)
•
Vih min = 1.771V
Vih max = 3.3V
•
SIM
•
T.B.D.
58
SIM_VCC
59
GND
•
(0V)
60
GND
•
(0V)
Table 2: Core Engine I/O Connector Pin Out
4.2 Core Engine I/O Signal Header [J4]
The Core Engine I/O signals can be accessed externally at a 60-pin header (connector J4
on the carrier board). The I/O interface signals are described in Table 2.
4.3 Ground Points [J2, J9]
Two ground points are provided (J2 and J9 on the carrier board) which can be used for
any probe hookup, for example to an oscilloscope.
4.4 RF Antenna Connector [J5, J6]
The RF antenna may be connected to the Core Engine modem directly, or to the carrier
board (at connector J6). When connecting the RF antenna to the carrier board, a cable
must also be connected from the carrier board (at connector J5) to the RF connector on
the Core Engine board.
The Core Engine board uses a muRata Microminiature SMT Coaxial Connector (muRata
p/n “MM9329-2700”) for RF antenna connection.
The carrier board uses an SMA connector for connection to an antenna, and a muRata
Microminiature SMT Coaxial Connector (muRata p/n “MM9329-2700”) for connection to
the Core Engine board RF connector.
The Core Engine modem is designed to support interchangeable antenna types, provided
that each antenna has 50-ohm impedance and has been tuned to the frequency band
intended.
4.5 Power [J7, J8, J10]
The Core Engine carrier board requires an input voltage of 3.7 VDC +/- 0.3V (connectors
J7, J8 & J10 on the carrier board).
CAUTION: The carrier board powers the Core Engine board directly, and so must be
used with a 3.7V (+/- 0.3V) power supply only.
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4.6 Primary Serial Interface [P3]
The primary serial I/O interface (connector P3 on the carrier board) implements RS-232
using a DB-9 connector and supports auto baud capability from 2400 bps to 115200 bps
with hardware handshake flow control.
Pin
Number
Signal
Name
Direction
Functionality
DCD0_DS
To CPE
Data Carrier Detect 0. DCE Output signal. Active low. Main
serial interface data carrier detect signal. Connects to a DTE,
CD, Carrier Detect pin.
RX0_DS
To CPE
Receive data 0. DCE Output signal. Main serial interface
transmit data signal. During idle or reset, signal will be a logic
1. Connects to a DTE, RX, receive data pin.
TX0_DS
From CPE
Transmit data 0. DCE Input signal. Active low. Main serial
interface receive data signal. During idle or reset, signal will
be a logic 1. Connects to a DTE, TX, transmit data pin.
DTR0_DS
From CPE
Data Terminal Ready 0. DCE Input signal. Active low. Main
serial interface data terminal ready signal. Connects to a
DTE, DTR, Data Terminal Ready pin.
GND_IN
From CPE
Electrical power return for digital and analog grounds.
DSR0_DS
To CPE
Data Set Ready 0. DCE Output signal. Active low. Main serial
interface data set ready signal. Connects to a DTE, DSR,
Data Set Ready pin.
RTS0_DS
From CPE
Request-To-Send 0. DCE Input signal. Active low. Main serial
interface request to send signal. Connects to a DTE, RTS,
Request-To-Send pin.
CTS0_DS
To CPE
Clear-To-Send 0. DCE Output signal. Active low. Main serial
interface clear to send signal. Connects to a DTE, CTS, Clear
to send pin.
RI0_DS
To CPE
Ring Indicator 0. DCE Output signal. Active low. Main serial
interface ring indicator signal. Connects to a DTE, RI, Ring
Indicator pin.
Table 3: Carrier Board Primary Serial Connector Pin Out
NOTE: The maximum length for the Primary Serial cable is 25 feet.
4.7 Secondary Serial Interface [P2]
The secondary serial I/O interface (connector P2 on the carrier board) implements RS232 using a DB-9 connector and supports auto baud capability from 2400 bps to 115200
bps with hardware handshake flow control.
Pin
Number
Signal
Name
Direction
Functionality
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Pin
Number
Signal
Name
Direction
Functionality
RX0_DS
To CPE
Receive data 0. DCE Output signal. Main serial interface
transmit data signal. During idle or reset, signal will be a logic
1. Connects to a DTE, RX, receive data pin.
TX0_DS
From CPE
Transmit data 0. DCE Input signal. Active low. Main serial
interface receive data signal. During idle or reset, signal will
be a logic 1. Connects to a DTE, TX, transmit data pin.
RTS0_DS
From CPE
Request-To-Send 0. DCE Input signal. Active low. Main serial
interface request to send signal. Connects to a DTE, RTS,
Request-To-Send pin.
CTS0_DS
To CPE
Clear-To-Send 0. DCE Output signal. Active low. Main serial
interface clear to send signal. Connects to a DTE, CTS, Clear
to send pin.
Table 4: Carrier Board Secondary Serial Connector Pin Out
NOTE: The maximum length for the Secondary Serial cable is 25 feet.
4.8 Primary Audio Interface [P1]
The primary audio interface (connector P1 on the carrier board) uses an RJ-9 connector
and provides differential microphone input and speaker output.
Pin
Number
Signal
Name
Direction
Functionality
MIC0N
From CPE
Microphone Negative. Negative input pin from an electrettype microphone. Nominal microphone differential voltage
should be 2.0 volts. Impedance not less than 900 ohms.
Leave signal disconnected if function is not used.
SPK0N
To CPE
Speaker Negative. Negative output pin. Low side of a
push-pull amplifier. Speaker impedance 15 ohms,
minimum. Speaker capacitance of 700 pF, maximum.
Driver voltage is 3.7V peak-to-peak. Leave signal
disconnected if function is not used.
SPK0P
To CPE
Speaker Positive. Positive output pin. High side of a pushpull amplifier. Speaker impedance 15 ohms, minimum.
Speaker capacitance of 700 pF, maximum. Driver voltage
is 3.7V peak-to-peak. Leave signal disconnected if function
is not used.
MIC0P
From CPE
Microphone Positive. Positive input pin from an electrettype microphone. Nominal microphone differential voltage
should be 2.0 volts. Impedance not less than 900 ohms.
Leave signal disconnected if function is not used.
Table 5: Carrier Board Primary Audio Port Connector Pin Out
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4.9 Secondary Audio Interface [J1]
The secondary audio interface (connector J1 on the carrier board) provides single-ended
microphone input and speaker output.
4.10 Audio Interface Select [JP2]
Selection of which audio interface is active is controlled by a jumper (jumper JP2 on the
carrier board). If the jumper is removed, the primary audio interface is active; if the
jumper is installed, the secondary audio interface is active.
This jumper is in parallel with the audio select pin (‘AUDIO_SEL’) on the Core Engine I/O
connector.
4.11 Subscriber Interface Module [J3]
The SIM, an integral part of any GSM terminal device, is programmed with subscriber
information. The SIM is not provided with the Core Engine unit and must be provided by
the GSM service subscriber. Care must be taken to protect the SIM. A GSM terminal will
not operate without the SIM installed.
The user information consists of an identity (IMSI number) registered with the GSM
provider, and an encryption Ki (pronounced key). The SIM consists of a microprocessor
chip and memory, installed on a plastic card. Core Engine uses the "mini-SIM" or plug in
configuration. The SIM, which is removable, installs in a holder (connector J3) on the
carrier board.
The SIM card performs authentication. To gain access to the GSM network, the network
must recognize the IMSI number and the terminal must be able to properly decrypt the
data sent by the network. The SIM also serves as a buffer for Incoming and Stored SMS
messages, or when a radio link is not available, store an outgoing message until a
network link is established.
NOTE: Power must be off when installing or removing a SIM card.
4.12 Status Indication [DS1]
The Core Engine carrier board provides a multi-color LED (DS1 on the carrier board) that
indicates the current link status and signal quality.
NOTE: The LED illuminates any time power is applied to the carrier board.
LED Color
Link Status
Green
Modem is attached to the network
Flashing Orange
Modem is registered on the network but is rejected
Flashing Red
Modem is in Start-up mode or is not attached to the network
Table 6: Carrier Board LED Colors
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NOTE: When the carrier board is not used, then to implement the LED status
indication using the I/O interface pins directly on the Core Engine modem using a
dual color LED requires two pins: “LED0_RMT” and LED1_RMT”. LED0 is red and
LED1 is green. To get the status indications, an inverter can be placed in between
the buffer output and the cathode, and the anode can be tied to 3V through a
220Ohm resistor. To achieve the status indications shown in the table, either LED0
will pulse on and off, or both LED0 and LED1 will pulse on and off together (giving
orange), or LED1 will be on steady. Otherwise the LEDs are not driven.
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5 POWER
5.1 Power Up Sequence
To power up the Core Engine, apply Vbat 3.7 Volts (+/- 0.3 Volts) to Core Engine I/O
interface pins 1-6 for VCC(+) and pins 7, 8, 11, 15, 19, 23, 24, 27, 33, 41, 44, 50, 59, 60
for GND(-).
The Core Engine will power up and will register on the network if an RF link is available.
5.2 Power Management
For maximum power savings some cooperation is required from the host device and
controlling software that interfaces to the Core Engine module. Mechanisms are provided
to allow the host to go to sleep and the Core Engine to wake the host, as well as for the
host to awaken the Core Engine.
Several power management levels (or power modes) are implemented in the Core
Engine.
5.2.1 Power Modes
5.2.1.1 “READY” Mode
The READY mode is characterized as follows:
AT+CFUN=1
The Core Engine is attached to the network.
PDP Context is activated.
Packet data transfer is in progress or imminent.
Full GSM operation for voice, data and SMS is possible.
The SLEEP signal on the Core Engine I/O interface is High.
5.2.1.2 “STANDBY” Mode
The STANDBY mode is characterized as follows:
AT+CFUN=1
The Core Engine is attached to the network.
Will transition to READY mode when an incoming message from the network is
detected.
Will transition to READY mode when an outgoing call is setup by the host.
The SLEEP signal on the Core Engine I/O interface is High.
Lower power than READY mode.
Reduced clock speed.
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5.2.1.3 “RF DISABLED” Mode
The RF DISABLED mode is characterized as follows:
AT+CFUN=4
The Core Engine is not attached to the network.
The RF section of Core Engine is powered down.
Limited functionality is available with the digital section (AT changes, phone book
entries, etc. are possible).
The SLEEP signal on the Core Engine I/O interface is Low.
Will transition to READY mode when the WAKEP_UP signal on the Core Engine I/O
interface is asserted.
5.2.1.4 “SLEEP” Mode
The SLEEP mode is characterized as follows:
AT+CFUN=0
The Core Engine is not attached to the network.
Reduced clock speed.
Minimal digital functionality.
The SLEEP signal on the Core Engine I/O interface is Low.
Will transition to READY mode when the WAKEP_UP signal on the Core Engine I/O
interface is asserted.
Will transition to READY mode when an “AT+CFUN=1” command is received.
Minimal power draw.
5.2.1.5 “DORMANT” Mode
The DORMANT mode is characterized as follows:
AT+CPWROFF
The Core Engine is not attached to the network.
The RF section of Core Engine is disabled.
The baseband section of Core Engine is stopped.
AT command interface is disabled.
The SLEEP signal on the Core Engine I/O interface is Low.
Will transition to READY mode when the WAKEP_UP signal on the Core Engine I/O
interface is asserted.
Will transition to READY mode when the RESET_B signal on the Core Engine I/O
interface is asserted.
Will transition to READY mode when a hardware reset (cycle power) is performed.
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5.2.2 Hardware Signals
5.2.2.1 “SLEEP” Signal
The SLEEP signal indicates whether or not the Core Engine RF section is active. When
the RF section is shutdown, the SLEEP signal will be Low. The SLEEP output is provided
if a host application wants to use it, but it is not necessary to use this pin. Usage would
depend on the host device and application. Some examples of when the SLEEP signal
may be useful are as follows:
Power down other host elements when the Core Engine radio is inactive: Monitoring
the SLEEP signal allows the host to detect when the radio is asleep so that other
elements of the host device may be powered down while there is no radio activity,
and so saving power.
Avoid multiple elements transmitting simultaneously: If the host device incorporates
another transmitting device (such as Bluetooth or 802.11) then the host may monitor
the SLEEP signal to confirm the Core Engine is not active before transmitting on one
of the other devices - it may be desirable to limit the implementation only one
technology or device is active or transmitting at once.
5.2.2.2 “PWR_DWN” Signal
The PWR_DWN signal triggers the software power down sequence (the same as the
AT+CPWROFF software command). The Core Engine will be released from the network
and the RF section will be shutdown. At this time the SLEEP signal will be Low. The
Core Engine will transition to “DORMANT” mode. The WAKE_UP signal or RESET_B
signal can be used to make the Core Engine re-activate and register on the network.
5.2.2.3 “WAKE_UP” Signal
The WAKE_UP signal will transition the Core Engine to the “READY” mode from the “RF
DISABLED”, “SLEEP” or “DORMANT” modes. The WAKE_UP signal (active Low) must
be held active for at least 10 microseconds.
5.2.2.4 “RESET_B” Signal
The RESET_B signal can be used to perform a complete restart the Core Engine, similar
to cycling power to the Core Engine. The RESET_B signal (active Low) must be held
active for at least 10 microseconds.
5.2.3 Software Commands
5.2.3.1 AT+CPWROFF
The “AT+CPWROFF” command will perform a graceful shutdown and transition the Core
Engine to the “DORMANT” mode. No subsequent AT commands will recognized by the
Core Engine until it is reset, either by cycling power or by either a WAKE_UP or a
RESET_B hardware signal.
5.2.3.2 AT+CFUN
The “AT+CFUN” command can be used to instruct the Core Engine to enter the “RF
DISABLED”, “SLEEP” or “DORMANT” mode, or to return to the “READY” mode. Unlike
the AT+CPWROFF command, the AT+CFUN command does not disable the Core Engine
AT command interface.
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NOTE: Refer to the Core Engine Programmer Reference documentation for the syntax
of how to use these software commands.
5.3 Transmit Power
The duration of a single transmit burst is 577 microseconds (uS). In Multislot Class 10
operation, two transmit slots may be concatenated, for a total of (577 uS x 2 = ) 1.54 mS.
The current required during the transmit burst is somewhat less than 2 Amps. This is
when running the full transmit power (30 dBm for PCS). The current required is
substantially less at the lower power levels.
A good way to estimate the current required at each power control level is to calculate the
current required to provide the transmit power to the antenna with a typical power
amplifier efficiency of 50%. For instance, to achieve 33 dBm transmit power to the
antenna, add about 2 dB to account for losses in the transmit filters and switches, so 35
dBm is required from the power amplifier output. Add another 3 dB to account for the
(typically) 50% power amplifier efficiency, so the power that must be delivered to the
power amplifier is 38 dBm. This is equal to 6.3 Watts. This requires about 1.7 amps at
3.7 Volts. This is the current required for the power amplifier stage only. The remainder
of the transmitter requires an additional 200 mA during the transmit burst (regardless of
transmit power level), for a total requirement of 1.9 Amps.
The capacitance required to sustain the transmit burst current can be estimated by
subtracting the current available from the power supply from the total burst current
required, and determining a suitable voltage droop during the burst. For instance, if 500
mA is available from the power supply, the capacitor will have to supply (1.9 - 0.5) = 1.4
Amps during the transmit burst time. If 300 mV is an acceptable voltage droop during the
transmit burst, the capacitance required would be C = (i*t)/V which would be
(1.4*0.00154)/0.3 = 7.2 milliFarad (7,200 uF).
Capacitor ESR must also be considered. Since the ESR multiplied by the current
produces a voltage step that increases the droop during the transmit burst, the lower the
ESR the better; 50 milliohms or less is preferred. Some of the "supercap" solutions on the
market may have unacceptably high ESR values.
These values are conservative estimates, and depending on the application, less
capacitance may give satisfactory performance. Dropping to a single transmit slot
operation (for example, Multislot Class 8 which uses 1 transmit and 4 receive slots) cuts
the capacitance required by half.
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6 SERIAL
COMMUNICATIONS
The Core Engine includes support for two (2) serial interfaces, Primary and Secondary,
which provide the means for the host to issue commands to and exchange data with the
Core Engine module. The host may utilize both serial ports of the Core Engine, or only
one, depending on the host requirements.
6.1 Supported Serial Port Configurations
6.1.1 Single Port Configuration
When only one serial port is used, that must be the Primary serial port; the Secondary
serial port is not used.
6.1.1.1 Single Port – Control and Packet Data
In a single port configuration, the Primary serial port can be used for the following:
AT commands
Voice control
SMS control
Circuit switched data
GPRS packet data
6.1.1.2 Single Port - Standard Protocol Support
Using the standard AT command interface to communicate with the Core Engine, AT
commands and traditional GSM operations (SMS, voice calls, circuit switched data) can
be performed on the Primary serial port, but these operations must be ended before the
port can be used for GPRS operations. This configuration facilitates “dial-up” type
applications, where a GPRS connection can be established, but must be terminated in
order to perform AT commands and GSM operations (including the notification or receipt
of incoming circuit switched calls and SMS messages).
NOTE: For full details of the AT commands supported refer to the separate document
Core Engine Programmer Reference, part number 07100027.
6.1.1.3 Single Port - Enhanced Protocol Support Using “XGAP”
In addition to the standard AT command interface, the Core Engine supports a proprietary
protocol that allows multiplexing of certain types of information on a single serial port.
This protocol, known as the Xircom GPRS Asynchronous Protocol (XGAP) provides the
capability to split the communications traffic on the single physical serial port into four (4)
distinct virtual channels.
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Using XGAP each virtual channel is used for one of the following types of
communications:
Command channel from host to baseband controller
Event channel from baseband controller to host
Packet data channel from host to baseband controller
Packet data channel from baseband controller to host
NOTE: For full details of the XGAP protocol implementation refer to the separate
document: Xircom GPRS Asynchronous Protocol (XGAP) Specification, part number
07300416.
Switching between the standard AT command interface and the XGAP interface is
accomplished using an AT command to select the desired interface.
NOTE: For full details of the AT commands supported refer to the separate document:
Core Engine Programmer Reference, part number 07100027.
6.1.2 Dual Port Configuration
When two serial ports are used, the Primary port can be used for AT commands and
traditional GSM operations (SMS, voice calls, circuit switched data), and the Secondary
port for packet data and GPRS operations. This configuration facilitates “always on”
applications, where a GPRS connection can be established and remain connected on the
Secondary port, while AT commands and GSM operations can performed on the Primary
port.
NOTE: In a dual port configuration, communications on the Secondary serial port must
use the proprietary XGAP protocol. The documentation in this section assumes XGAP
is implemented on the Secondary serial port. For full details of the XGAP protocol
implementation refer to the separate document Xircom GPRS Asynchronous Protocol
(XGAP) Specification, part number 07300416.
6.1.2.1 Dual Port - Primary Port: Control & Circuit Switched Data
In a dual port configuration, the Primary serial port can be used for the following:
AT commands.
Voice control.
SMS control.
Circuit switched data.
NOTE: In a dual port configuration, there is no GPRS packet data capability on the
Primary serial port.
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6.1.2.2 Dual Port - Secondary Port: Packet Data Using “XGAP”
In a dual port configuration, the Secondary serial port using the Xircom GPRS
Asynchronous Protocol (XGAP) can be used for the following:
AT commands.
Voice control.
SMS control.
GPRS Packet Data.
NOTE: Since circuit switched data is streaming rather than packet based, in a dual port
configuration there is no circuit switched data capability on the Secondary serial port.
XGAP provides the capability to split the communications traffic on the single physical
serial port into four (4) distinct virtual channels. Each virtual channel is used for one of the
following types of communications:
Command channel from host to baseband controller
Event channel from baseband controller to host
Packet data channel from host to baseband controller
Packet data channel from baseband controller to host
NOTE: For full details of the XGAP protocol implementation refer to the separate
document: Xircom GPRS Asynchronous Protocol (XGAP) Specification, part number
07300416.
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7 AUDIO
The Core Engine includes two (2) audio interfaces, each with support for one (1)
microphone and one (1) speaker.
7.1 Audio Path Selection
Selection of which mic/speaker pair should be active is achieved either by hardware,
using a designated signal on the Core Engine I/O connector, or by software, using an AT
command.
7.1.1 Hardware Selection of Audio Path
The AUDIO_SEL signal on the (pin 34 of the Core Engine I/O interface) can be used to
select whether the Primary or Secondary mic/speaker should be active.
7.1.2 Software Selection of Audio Path
The “AT+SPEAKER” software command can be used to select whether the Primary or
Secondary mic/speaker should be active.
NOTE: Refer to the Core Engine Programmer Reference documentation for the syntax
of how to use this software command.
7.2 Microphone Input
The Core Engine microphone (input) interface specification is shown in Table 8:
Input voltage differential
1.03Vpp
Differential input resistance
50Kohm
Input capacitance
5pF
Table 7: Core Engine microphone interface specification.
Each microphone circuit should have its own RC filtering on the bias supply. Microphone
characteristics vary and exact biasing values may need some experimentation. The
microphone inputs are multiplexed (not summed) into the voiceband receive circuit.
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7.3 Speaker Output
The Core Engine speaker (output) interface specification is shown in Table 9:
Differential output voltage typical
3.7V
Output differential maximum DC offset
100mV
Differential output load resistance minimum
15ohm
Output load capacitance maximum
4700pF
Table 8: Core Engine speaker interface specification.
The baseband is powered at 2.5V in the audio circuit design. The minimum load is 15
ohms.
The 3.7V peak-to-peak specification is a differential measurement with the reference of
SPK_N1 or SPK_N2 (pins 9 and 36 respectively of the Core Engine I/O interface). Each
SPK_xx positive/negative pair can swing approximately 1.85V peak, with respect to
ground. The 3.7V peak-to-peak is obtainable because the SPK_Px positive is 180
degrees out of phase with the negative. Since this occurs simultaneously, the differential
measurement is (2 * 1.85V), or 3.7V peak-to-peak.
There is no audio power amp component in our design. The signals are driven directly by
the baseband processor.
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7.4 Audio Circuit Implementation
7.4.1 Example Single-Ended Microphone Circuit
Figure 3 shows an example of how to implement a single ended microphone circuit
compatible with the Core Engine.
Figure 2: Single-Ended Microphone Circuit (Example)
NOTE: The FB1, FB2 and FB3 components are ferrite beads to suppress any energy
on to the headset cord. Component D3 is a transient surge suppressor to protect
against ESD.
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7.4.2 Example Differential Microphone Circuit
Figure 4 shows an example of how to implement a differential microphone circuit
compatible with the Core Engine.
Figure 3: Differential Microphone Circuit (Example)
7.5 Microphone Cable Considerations
The differential circuit design in the Core Engine baseband processor has excellent
common mode voltage rejection for noise signals.
If the microphone is located reasonably close to the Core Engine module, it should be OK
to use unshielded cable. However, this also depends on where the cable is routed. Slight
TDMA framing noises may be noticed if the cable is close to the antenna.
It is recommended that a twisted pair cable be used from the Core Engine microphone
connector to the microphone element. If problems arise, then a shielded cable (i.e.
termination of the shield) may be used.
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8 RF ANTENNA
8.1 Antenna Connector
The Core Engine modem includes an on-board RF antenna connector. The modem is
designed to support interchangeable antenna types provided they have impedance of 50
ohms.
The Core Engine on-board RF antenna connector is a MuRata Microminiature SMT
Coaxial Connector (muRata p/n “MM9329-2700”).
8.2 Antenna Selection
The selection of an antenna for use with any radio or radio system, whether integrated of
remote, is a process that cannot be taken to lightly. To simplify the process and identify a
few key performance metrics is difficult to do since antennas are extremely sensitive to
the environment in which they are placed. If the antenna is integrated into a plastic cover
that will be used in a handheld device, then all antenna performance measurements
should be made with the integrated solution held in a hand, or hand simulator. Similar
measurement criteria should be used for units used near the head, on a tabletop, wall,
etc. In this way, the antenna can be tuned for best performance while operating in the
environment that it will be expected to operate in when used by the customer.
As a result, the following criteria assumes that, as a minimum, the antenna is being
measured as it will be used in the final product, i.e. either integrated with the radio or in
free space.
8.3 Antenna Performance Guidelines
8.3.1 Antenna Impedance Match
The antenna impedance within the operating bands of interest should match the
impedance of the radio RF port for maximum power transfer.
Almost universally the antenna port impedance is 50 ohms. The metric used to determine
how well the antenna is matched to 50 ohms is called the return loss or VSWR. These
values can be used to calculate the mismatch loss, which in turn can be used directly as a
loss in the overall system link budget. For a mismatch loss of 1 dB or less, the return loss
must be less than –7 dB (VSWR less than 2.6:1) across all bands of operation. A return
loss of –9.5 dB (VSWR = 2.0:1) results in a mismatch loss of –0.5 dB.
It should be noted that a large impedance mismatch at the antenna port could lead to
more severe losses in radio performance than those calculated here. This is due to the
fact that the radio power amplifier/low noise amplifier and filtering circuits are tuned for
peak performance with a 50 ohm load. Any deviation from this matching impedance will
cause a load line deviation for these devices, which if very large (VSWR > 2:1), can cause
serious degradation to the power output, noise figure, or filter frequency response of the
radio.
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8.3.2 Antenna Pattern and Gain
The antenna pattern shape should be consistent for all frequencies of operation. The
radiation pattern shape and maximum gain should be consistent with the radio link
performance objectives and the anticipated deployment configurations. This combination
of factors will determine if a directional or omni-directional antenna pattern shape is
desired. In general, for a portable device the antenna pattern shape should be omnidirectional with a peak gain that is less than 2dBi and an average total field gain (vertical
and horizontal polarization combined response) that is -4dBi or greater.
Directional antennas can be used for wall mount applications. These antennas should
have a directional radiation pattern with a peak gain broadside to the antenna. For most
applications, these antennas should have a 10 dB front-to-back ratio as a minimum. The
peak gain will be a function of the system performance requirements and regulatory
allowances.
FCC requirements limit the amount of antenna gain permissible. The combination of
antenna and cable loss (if any) must be selected to maximize path gain within the FCC
requirements (maximum of 3dBi for mobile and 7dBi for fixed applications).
8.3.3 Antenna Beam Width
For mobile applications, the installer should select an omni-directional antenna with good
elevation beam width. With an omni-directional antenna, you trade some gain (azimuth)
for an increased elevation beam width (elevation). Good omni-directional antennas with
2-3dBi gain, and a good elevation beam width are readily available.
Fixed applications could use any type of antenna because there is more flexibility in gain,
but unless the installation site is on the outer fringes, or in a deep fade area, (major
obstructions) gain is the most important thing. Again, you trade gain for beam width
(azimuth and elevation).
The Installer should keep in mind that networks and site environments change. For
example, new cell sites are added to expand existing coverage and/or capacity. With this
growth, new obstructions are added as well, which could change the signal quality for
fixed applications (e.g. a newly constructed building).
Therefore, it is recommended that the installer not install highly directional antennas
attempting to pinpoint the link to a serving base station. Due to the FCC restrictions, the
installer should be able to find a good performing antenna, which provides decent gain,
and good beam width performance.
In order to accomplish “seeing” as much of the network as possible, the installer is
advised to use as broad of a beam width as possible (and reasonable given any particular
installation).
Installation using these guideline, avoid potential problems such as:
New base station sites, installed closer to site but which cannot be "seen" by
the network.
Serving cell taken out of service temporarily, but the network lacks the ability
to jump to other cell sites
Newly constructed obstructions, resulting
environmental characteristics.
in a
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8.3.4 Antenna Polarization
Antenna polarization is normally defined as vertical, horizontal, slant left, slant right, or
circular. For portable devices, polarization purity is not required nor desired. Due to the
random positions that a portable device can be used in, and due to the fact that a
significant de-polarization of the predominantly linear polarization of the serving base
station will occur in most user environments, it is important that a portable device have an
antenna that will respond well to all polarizations. This is generally known as “dirty”
polarization and can be described as a polarization ellipse with an axial ratio (ratio of the
maximum to minimum response of the polarization ellipse) of 7 to 9 dB.
8.4 Antenna Location and Network Communication
The antenna location for modem installation is dependent on the individual site conditions.
As a rule, the antenna should be positioned so that a reliable radio connection can be
made with the GSM network. The following guidelines will assist the installer in making
this determination.
Where the reliability of the signal strength would be in question, one or more base
stations would enhance quality of the signal.
Where possible, the modem location should be selected so that the antenna has an
unobstructed line of sight to the selected base-station(s)
The antenna should be located to maximize the signal strength and quality received
from the selected base-station(s).
It is recommended that the installer obtain GSM Network coverage maps from the
GSM operator indicating that the installation site is in a covered area. It is also
recommended that coverage and signal quality be verified prior to installation, using a
GSM handset.
If possible, the modem and its associated antenna should be deployed inside an
environmentally controlled protected structure (such as an office building).
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9 PROVISIONING THE SIM
The GSM SIM can support optional features or services. Most GSM operators typically
configure the SIM to send/receive voice calls and to receive SMS; however, some may
require an additional tariff to enable the SIM to send SMS. The transmission of data and
fax are also additional services that may require tariffs and additional provisioning. Each
of these services has two separate modes that must be enabled to allow the service:
Mobile-originated (MO): allows making a service request (such as, making a call or
sending an SMS)
Mobile-terminated (MT): allows receiving a service request (such as, receiving a
phone call or an SMS)
It is imperative for the Core Engine modem that the SIM be configured for the optional
services that are required for the application.
9.1 GSM Services Supported by the Core Engine modem
The Core Engine modem supports three (3) GSM services (modes of operation) that must
be enabled by the operator:
Voice calls (MO and MT): requires a telephone number
SMS (MO and MT): uses the telephone number for Voice
Circuit-switched data calls (MO and MT): requires a telephone number
The GSM SIM can have multiple telephone numbers: one number for voice calls and SMS
and one number for data calls.
9.2 Selecting the Modes of Operation
When provisioning the SIM for the Core Engine modem, enable the following modes of
operation:
Voice calls: configure the SIM for both MO and MT service (to send and receive)
SMS: configure the SIM either for MT alone (to receive) or for both MO and MT (to
send and receive)
Data: configure the SIM either for MO alone (to send) or for both MO and MT (to send
and receive)
Voice
SMS
Data
Function
MO/MT
MT
MO
Voice calls, receive SMS, make data calls
MO/MT
MT/MO
MO
Voice calls, receive/send SMS, make data calls
MO/MT
MT/MO
MO/MT
Voice calls, receive/send SMS, make/receive data calls
(requires an additional data telephone number)
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10 INSTALLATION &
INITIALIZATION
10.1 Installation and Verification
10.1.1 Installation
10.1.1.1 Install SIM card.
NOTE: The SIM card is supplied by the service provider, and is not supplied by Xircom.
The Core Engine unit will not operate without a properly coded SIM card installed.
Disconnect all power to the unit before installing the SIM card.
Install the SIM card in the SIM card slot (connector J7) on the Core Engine carrier
board.
10.1.1.2 Terminal Connect & Setup
Connect the Terminal to the Primary Serial Port (DB-9) connector (P5 on the carrier
board) using a standard (straight thru) modem cable. The diagnostic terminal can be a
laptop PC, with a serial port connection, running a program such as ProComm or other
communication application.
Set up the diagnostic serial communication to the Core Engine default values:
Baud Rate
9.6 Kbps
Stop Bits
Data
8 bits
Parity
No
Duplex
Full
Table 9: Core Engine default serial interface values.
10.1.1.3 Connect Power Supply Cable
Install the power supply per manufacturer’s recommended procedures. Plug the power
supply cable plug into the modem power connector (J17 or J18). The connector is keyed
so it can only be installed one way. The connector also has an automatic locking feature
that will engage when the connector pair is fully mated and is easily releasable with finger
pressure.
10.1.1.4 Verify all Terminal Connections
Check that all Core Engine connections have been installed per the instructions in this
manual, and that the power cable (or cord) is secured with no exposed wires.
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10.1.1.5 Apply Power
10.1.2 Verification
10.1.2.1 Using AT Commands
In the GSM vocabulary, a call from GSM mobile to the PSTN is called a "mobileoriginated call" or "outgoing call." A call from the fixed network to a GSM mobile is called a
"mobile-terminated call" or "incoming call."
In the following examples, “App” refers to the application. The following convention
describes the direction of the data exchange:
The data exchange from the customer application to the Core Engine modem is
designated as: App > Modem
The data exchange from the Core Engine modem to the customer application is
designated as: Modem > App
NOTE: With the exception of the +++ command (Online Escape Sequence), all
commands must be preceded by the AT attention code (or command prefix) and
terminated by pressing the  character.
In the following examples, the  and  are intentionally omitted for clarity
and space.
10.1.2.2 Initial Response to the AT Command
After power is applied to the Core Engine, the modem performs a power-up self-test.
When queried with the AT command, the Core Engine modem responds with one of the
following result codes:
OK signifies that the Core Engine modem is ready, that it correctly interprets the AT
command, and that it can execute the command.
ERROR signifies that the Core Engine modem does not understand the command or
that the command is invalid.
App > Modem
AT
Modem > App
OK
Command valid: modem is ready
The Core Engine modem must be in Command mode when any command is entered
(with the exception of the online escape sequence +++). Commands entered when the
modem is in Online mode are treated as data, and are transmitted as such to the
receiving modem.
10.1.2.3 Modem Initialization
The following example provides the sample AT commands and responses for the
following initialization tasks:
Disable character echo
Set the modem to Verbose mode (to display result codes as words)
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Set the DCD to ON
Monitor the DTR
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App > Modem
ATE0Q0V1&C1&D0
Initialization string
Modem > App
OK
Command is valid
App > Modem
ATS0=1
Auto answer on 1st ring
Modem > App
OK
Command is valid
10.1.2.4 SIM PIN Status
The following example provides the AT command and response for querying the PIN
status and entering the SIM PIN number if required.
App > Modem
AT+CPIN?
Query the SIM PIN status
Modem > App
+CPIN: Ready
GSM terminal is not waiting for any password
OK
+CPIN: SIM PIN
terminal is waiting for PIN
+CPIN: SIM PUK terminal is waiting for PUK
ERROR
SIM is not installed
If the response is +CPIN:Ready, then skip the remainder of this paragraph. If the
response is +CPIN:SIM PIN then proceed with the remainder of this paragraph to enable
the terminal by entering the SIM PIN.
CAUTION: Use care when entering the SIM PIN. If it is entered incorrectly three times
in a row, the GSM terminal will lock and a SIM PUK is required to unlock the SIM.
App > Modem
AT+CPIN=”1234”
Enter the PIN number
Modem > App
OK
Command is valid
App > Modem
AT+CPIN?
Query the SIM PIN status
Modem > App
+CPIN: Ready
GSM terminal is not waiting for any password
OK
+CPIN: SIM PIN
terminal is waiting PIN
If the response is +CPIN:Ready, then skip the remainder of this paragraph. If the
response is +CPIN:SIM PIN then carefully verify that you have the correct SIM PIN and
repeat the SIM PIN entry.
10.1.2.5 Data Call Setup (modem origination)
The following example provides the AT command and response for setting the Core
Engine modem for 9600 baud, non-transparent mode.
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App > Modem
AT+CBST=7,0,1
9600 baud, non-transparent mode
Modem > App
OK
Command is valid
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10.1.2.6 Modem Status Commands
The following examples provide the AT commands and responses for querying the status
of the unit.
The following command checks to determine if the Core Engine modem has
successfully registered with the GSM network.
App > Modem
AT+CREG?
Get the registration status
Modem > App
+CREG: 0,1*
Registered with home network
OK
+CREG=0,2 registration in progress
+CREG=0,5 registered as roaming
*First character can be “0” or “1”: “0” for manual response, “1” for auto response.
The following command queries the strength of the RF coverage. This command
provides information about the RF coverage for the Core Engine modem.
App > Modem
AT+CSQ
Get the signal strength (for this command, do not
enter “?”)
Modem > App
+CSQ: 20,99
Receive signal strength = 20, -74 +/- 1 dBm
OK
RXQUAL =99, unknown
RSSI (dBm)
Value
Value
RSSI (dBm)
+/- 1 dBm
< -110
16
-82
-110
17
-80
-109
18
-78
-108
19
-76
-106
20
-74
-104
21
-72
-102
22
-70
-100
23
-68
-98
24
-66
-96
25
-64
10
-94
26
-62
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11
-92
27
-60
12
-90
28
-58
13
-88
29
-56
14
-86
30
-54
15
-84
31
-52
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Table 10: RSSI vs. Received Signal Power
Value
RSSI (dBm)
BER < 0.2%
0.2% < BER < 0.4%
0.4% < BER < 0.8%
0.8% < BER < 1.6%
1.6% < BER < 3.2%
3.2% < BER < 6.4%
6.4% < BER < 12.8%
12.8% < BER
Table 11: RXQUAL vs. Bit Error Rate
The following command requests the current Public Land Mobile Network (PLMN).
DeTeMobil is used as an example, the PLMN may be different.
App > Modem
AT+COPS?
Request current PLMN
Modem > App
+COPS:
0,0,”DeTeMobil”
PLMN is DeTeMobil
OK
10.2 SMS Message Verification
10.2.1 Modem Sent SMS (Text)
To be able to send SMS text messages, the Core Engine modem must be initialized with
the proper SMS mode. The following examples provide the AT commands and responses
for initializing the SMS mode.
The following command initializes the Core Engine modem by setting the text mode
parameters.
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App > Modem
Modem > App
AT+CSMP=17,167,0,0
OK
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Set text mode parameters:
17: Sets reply pat, user data header,
status report request, validity period
format, reject duplicates and
message type
167: Sets validity period
0: Higher layer protocol indicator
0: Information encode format
Command is correct
After initializing the modem with the proper SMS mode, select the proper service
center. The service center is the Public Land Mobile Network (PLMN) to which the
SME telephone number belongs. The following command selects the service center.
Voicestream is used as an example, the users home PLMN may be different.
App > Modem
AT+CSCA="+491710760000"
Modem > App
OK
Service center initialization:
D1 – Germany
The following command selects TEXT mode for SMS messages.
App > Modem
AT+CMGF=1
Set message format to TEXT mode
Modem > App
OK
Command is correct
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The following command sets the indicators for the message.
App > Modem
AT+CNMI=1,1,0,0,0
Set the new message indicators
AT+CNMI=,,,,
Modem > App
OK
=1, discard unsolicited result
codes indication
=1, SMS-DELIVERs are routed using
unsolicited code
=0, no CBM indications are routed
to the TE
=0, no SMS-STATUS-REPORTs
are routed
=0, TA buffer of unsolicited result
codes defined within this command is
flushed to the TE
Successful command
The following command saves the SMS settings. Once the SMS commands have
been saved, the initialization commands do not need to be sent again until they are
changed.
App > Modem
AT+CSAS
Save SMS settings
Modem > App
OK
Successful transmission
After the Core Engine modem has been initialized, the following commands and
sample responses provide the telephone number and the message to be transmitted.
App > Modem
AT+CMGS="12017572673"
Send a message to the telephone
number (insert user modem phone
number as the value in parenthesis)
Modem > App
Ready to send message
App > Modem
Hello, how are you?^Z
Enter the text message.
message with Control Z.
Modem > App
+CMGS: 1
Successful transmission
OK
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End
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10.2.2 Modem RECEIVE SMS (Text)
The following example provides the AT command for requesting that the Core Engine
modem list received SMS messages. This string requests that the modem send (over the
RS232 interface) all of the messages that have been received.
App > Modem AT+CMGL=”ALL”
Read ALL messages received, including status,
originator, message number and message content
(if messages are present)
Modem > App +CMGL: 1, "REC UNREAD", "12017572673"
Hello, how are you?
OK
10.2.3 SIM Data Provisioning Verification (Optional)
At this time the user has the option of verifying the data communications function from the
users system application to the modem prior to connection to the CPE. To check this
path, have the user’s system application send a data stream to the modem and observe
the data stream on the diagnostic terminal for verification of correct performance.
10.2.4 Match Modem Serial port to CPE
The modem is now ready to be interfaced with the CPE. The serial port settings, data
type, and flow control between the modem and the CPE need to be matched. Reference
Table 9 for the Core Engine modem initialization defaults.
1. Match the bearer type selection (transparent deviation on different sheet or nontransparent data).
2. Match the flow control.
3. Match the serial interface parameters (baud rate, 8 data bits, 1 stop bit, no parity).
4. Set up the terminal serial interface parameters to match the modem (if modem has
changed).
5. Save parameters to non-volatile memory. (AT&W command, AT+CSAS)
10.2.5 Verify Setup
1. Power down the unit
2. Wait 5 seconds and then re-apply power to verify commands were saved properly
3. Power down again.
10.2.6 Connect Primary Serial Port Cable
Plug the RS232 cable from the CPE into the Primary Serial Port connector (DB-9) on the
Core Engine carrier board. The connectors are keyed so it can only be installed one way.
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10.3 Final Verification
10.3.1 SMS Verification
Repeat the SMS Message Verification section.
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11 DETAILED
SPECIFICATIONS
11.1 Physical Dimensions and Weight
Size (L x W x H) including connectors
53.09 mm x 34.80 mm
(2.09” x 1.37” x 0.22”)
Weight
15 g (0.5 oz.)
5.66 mm
Table 12: Core Engine Size and Weight
11.2 Operating Power
The Core Engine carrier board requires an input voltage of 3.7 VDC +/- 0.3 VDC. The
input source voltage ripple should be less than 20% of the average supply voltage peakto-peak under normal operating conditions.
Core Engine modem
PCS 1900
Average Current (Amps)
Peak Current (Amps)
Ready Mode
(GSM)
1 TX, 1 RX
TBD
TBD
1 RX
TBD
TBD
Ready Mode
(GPRS Class 10)
1 TX, 4 RX
TBD
TBD
2 TX, 3 RX
TBD
TBD
Standby Mode
N/a
TBD
N/a
RF Disabled Mode
N/a
TBD
N/a
Sleep Mode
N/a
TBD
N/a
Dormant Mode
N/a
< 100uA
N/a
Table 13: Core Engine Power Modes & Current Requirements
11.2.1 Transmit Power
Core Engine
modem
Power Class
Transmit Power
1900 MHz
GSM Power Class 1
1-W conducted power maximum
measured at the antenna port
Table 14: Core Engine Transmitted Output Power
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11.2.2 Receiver Sensitivity
The receiver sensitivity measured at the antenna port is -106 dB (typical) and -104 dB
(minimum).
11.3 Care and Maintenance
The Core Engine modem should be used in a protected environment.
The internal
components of the modem must remain dry and free of moisture. Avoid installations in
extremely cold or hot locations, and avoid extreme temperature changes during use.
There are no external or internal maintenance requirements.
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12 ENVIRONMENTAL
SPECIFICATIONS
12.1 Climatic
Internal circuitry provides automatic shutdown control to prevent the unit from operating above
or below the specified operating temperature range.
12.1.1 Climatic: Operational
Operating temperature
-20°C to +55°C
NOTE: Upper temperature range can be extended under
certain operating conditions.
Relative humidity
5 - 95%
Solar radiation
Not Applicable
Air pressure (altitude)
70 kPa to 106 kPa (-400 m to 3000 m)
12.1.2 Climatic: Storage and Transportation
Duration
24 months
Ambient temperature
-40°C to +85°C
Relative humidity
5% to 95%, non condensing (at 40°C)
Thermal shock
-50°C to +23°C, +70°C to +23°C; < 5 min
Altitude
-400 m to 15,000 m
12.2 Mechanical
12.2.1 Mechanical: Operational
Operational vibration, sinusoidal
3.0 mm disp, 2 to 9 Hz; 1 m/s , 9 to 350 Hz
Operational vibration, random
0.1 m /s , 2 to 200 Hz
12.2.2 Mechanical: Storage and Transportation
Transportation vibration, packaged
ASTM D999
Drop, packaged
ASTM D775 method A, 10 drops
Shock, un-packaged
150 m/s , 11 ms, half-sine per IEC 68-2-27
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Drop, un-packaged
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4-inch drop per Bellcore GR-63-CORE
12.2.3 Mechanical: Proposed Standards
Transportation
ETSI Standard ETS 300 019-1-2 Class 2.3 Transportation
Operational
ETSI Standard ETS 300 019-1-3 Class 3.1 Operational
Storage
ETSI Standard ETS 300 019-1-1 Class 1.2 Storage
12.3 Electromagnetic
12.3.1 Electromagnetic Emissions
Radiated spurious
FCC part 24 / Part 15 Class \ B
GSM 11.10 Section 12.2
EN 55022 Class B
12.3.2 Electromagnetic Immunity
TBD
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13 GLOSSARY AND
ACRONYMS
App
Application
Refers to the Application which sends or receives
commands/responses from the Core Engine modem
AT Command Set
Commands issued by intelligent device to a modem to
perform functions, such as to initiate call, to answer call, or
to transmit data.
CSD
Circuit Switched Data
Data link from a terminal through the network allowing realtime, duplex connectivity up to 9600 bytes/second.
CE
European Community
Certification
CPE
Customer Premise Equipment
A terminal in fixed location on the customer’s premises.
Dbi
Decibels referenced to an isotropic radiator
DCE
Data Communications
Equipment
Data Communications Equipment
DCS
Digital Cellular System
A collection of services and capabilities providing flexibility
of access and mobility through a combination of wireless
and wire-line networks, utilizing the 1800 MHz bandwidth.
DTE
Data Terminal Equipment
Data Terminal Equipment
EFR
Enhanced Full Rate
Voice (vocoder) compression algorithm which offers the
highest quality voice communication.
EIR
Equipment Identity Register
A database used to store International Mobile Equipment
Identity (IMEI) of a locally issued terminal.
EIRP
Equivalent Isotropic Radiated
Power
In a given direction, the gain of a transmitting antenna
multiplied by the net power accepted by the antenna from
the connected transmitter.
ESD
Electrostatic Discharge
Static electricity that can damage electronic equipment.
FTA
Full Type Approval
GSM Full Type Approval
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FCC
Federal Communications
Commission
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US Government body that defines requirements for
emission level of equipment in the United States.
GPRS
General Packet Radio Service
Standard for packet communications utilizing Global
Standard for Mobility (GSM) infrastructure.
GSM
Global System for Mobile
Communications
Standard for digital communications. Allows consistent
communications in various parts of the world despite
variations in RF spectrum allocations. Transferring the SIM
(see below) permits users to roam by changing terminal
equipment.
IMEI
International Mobile Equipment
Identity
A unique number for each GSM Terminal tracked by the
GSM operators in their Equipment Identity Register (EIR)
database.
Ki
A secret code used in authentication and encryption by the
terminal.
LED
Light Emitting Diode
Light Emitting Diode
MMS
More Messages to Send
More Messages to Send
MO
Mobile Originated
A voice or data call originated at the mobile terminal.
MT
Mobile Terminated
A voice or data call originated from the network and sent to
the mobile terminal.
Non-Transparent Mode
Delivers a constantly low error rate but with a nonguaranteed throughput or delay. The Non-Transparent
service provides a performance that is closest to using a
modem over a fixed PSTN line.
NRTL
Nationally Recognized Test
Laboratory
OSHA-approved Nationally Recognized Testing Laboratory
OEM
Original Equipment Manufacturer
Packet
A collection of data transmitted over a digital network in a
burst.
PCS
Personal Communications
Service
A collection of services and capabilities providing flexibility
of access and mobility through a combination of wireless
and wireline networks.
PDU
Protocol Data Unit
Data packet defined by protocol layer of SMS interface.
PLMN
Public Land Mobile Network
PSTN
Public Switched Telephone Network
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RF
Radio Frequency
A frequency at which electromagnetic radiation may be
detected and amplified as an electric current at the wave
frequency.
Rx
Receive
Short Message
An alphanumeric message of up to 160 characters that can
be sent to or from a GSM terminal.
SIM
Subscriber Identification Module
“Smart Card” technology that contains user information and
has four main functions:
Authentication
Storage of data
Assist in encryption process
Subscriber protection
SMS
Short Message Services
Services provided by GSM network allowing the
transmission and receipt of short messages.
SMSC
Short Message Service Center
Location of SMS store and forward message server.
TBD
To Be Determined
Transparent Mode
Delivers a service with a variable error rate, with a
guaranteed throughput and delay.
Tx
Transmit
Type Approval
Rigorous testing required by GSM operators to ensure
terminals operating on network does not degrade
performance, capacity, or functionality of GSM network.
UL
Underwriters Laboratory
Testing agency chartered with ensuring safety of electrical
devices.
USSD
Unstructured Supplementary Service Data
V.24 Serial Interface
The ITU-T standard defining interchange circuits between
DTE and DCE. V.24 is the ITU-T equivalent of EIA standard
RS-232, with the exception of voltage levels.
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14 UPDATING THE CORE
ENGINE FIRMWARE
The Core Engine firmware may be downloaded from a host computer to the Core Engine
through the Core Engine primary serial port. The host computer that holds the firmware
update utilities and the new files that are to be downloaded to the Core Engine must be
connected to the Core Engine primary serial port before the Core Engine is powered up.
When the Core Engine is powered up, it will look for a specific signal on the primary port.
If none is detected, then the Core Engine will boot normally. If a special signal is detected
on the primary serial port at the start of the boot sequence, then the Core Engine will stop
the normal boot sequence and instead it will start the firmware update process.
In addition to the firmware image file to be downloaded to the Core Engine, there are a
number of utility programs required in order to perform the download.
14.1 Required Files
To download a new firmware image, the following files are required:
serload.exe
flash.hex
egload.hex
newstack.hex
14.2 Download Utility
The software utility used to perform the firmware download is called “serload.exe”.
The download utility works with Windows 95, 98, 2000, and NT, and can be run from a
command line prompt within Windows.
The utility accepts several command line parameters, which determine the host serial port
to use as well as the communications speed to use for the download. Information about
the supported command line parameters can be displayed by issuing a command to run
the utility without any command line parameters.
The command line for information is:
serload
where:
serload
is the download utility program name
Figure 5 shows the display of information on supported command line parameters.
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Figure 6: Serial Loader Session (Example)
14.3 Download Procedure
IMPORTANT: The Core Engine should be powered off before starting the download
utility.
The command line to perform a download is:
serload newstack.hex 1f
where:
serload
is the download utility program name
newstack.hex is the firmware image file (Note: the actual filename may vary)
1f
is the host computer Com port (e.g. Com1) and speed (f for fast)
The download utility will display several lines of information, then it will pause after
displaying the length of Partition 1 and Partition 2, and a spinning line prompt will appear
indicating the utility is ready to communicate with the Core Engine. Once this prompt
appears the Core Engine can be powered up.
IMPORTANT: Wait for the spinning prompt in the lower left hand corner before
applying power to the Core Engine.
Once power is applied to the Core Engine the utility will display a confirmation that a
communications link has been established, then it will proceed with the download.
The download should take about 4-5 minutes to complete. A successful download will be
indicated by a checksum verification message.
Figure 6 shows an example of a firmware download session.
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Figure 6: Serial Loader Session (Example)
NOTE: After the download is complete you must reset the Core Engine to start the
new firmware.
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15 INSTALLING A REMOTE
ANTENNA
There are a number of antennas designed for use with the Core Engine modem. If
coverage is poor then the use of a remote antenna may be required. Ideally, the external
antenna is mounted on a rooftop, or on the side of a building where optimal signal
strength can be obtained.
15.1 Antenna Coaxial Cable and Connectors
In most cases RG223 50 ohms or similar small diameter cable can be used. For outdoor
installations, the coaxial cable must be rated for outdoor exposure.
For either fixed or mobile applications, if the antenna has less than a 3 dB gain and a
separation distance of greater than 20 cm (7 7/8 inches) from the body of the antenna,
and any nearby person(s), then the installation will comply with current FCC requirements
addressing human exposure to radio frequency electromagnetic fields.
NOTE: The installer is responsible for assuring that the proper antenna is installed
so that the above limits are not exceeded.
15.2 Outdoor Antenna Grounding
Any outdoor antenna used to transmit or receive RF signals and the antenna connecting
cables must be properly grounded to comply with the National Electrical Code (NEC) specifically, but not limited to, articles 250, 800, 810, 820.
Codes require proper grounding of the cables at the point where they enter a building.
Local building codes may also be applicable. For clarification on either local or national
grounding requirements, contact the state or county inspection officials in your location.
15.3 Coaxial Cable Routing
When surveying a site for external antenna installation, verify that there is a suitable path
for the antenna cable from the antenna to the RF antenna connector on the modem. The
coaxial cable must be supported along its path, and protected to assure that damage
does not occur.
NOTE: All cables require routing to be free from any obstacles or any other type of
interference that may cause the cable to be damaged or undergo later damage to
the shielding or cable casing.
Installation of the cables should be in accordance with the manufacturer’s instructions, the
National Electrical Code, applicable building codes, and general industry standards and
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practices. Emphasis on freedom from obstacles, and the aesthetic guidelines required by
site management should be taken into consideration during the install.
NOTE: Coaxial cables must be professionally installed. Coaxial cables must be
routed and installed in a manner that insures that the jacket, dielectric and outer
shield are not crushed, kinked, cut, scraped or otherwise damaged.
15.4 Coaxial Cable Losses and Lengths
There are some important factors to consider concerning coaxial cable length. The FCC
requires that for mobile applications, the maximum output power can be no more than 2
W (+33 dBm) EIRP, and for fixed applications, no more than 5W (+37dBm). When
using a directional gain antenna and short coaxial cable connections, it is possible to
exceed either FCC requirement. In such cases, additional attenuation must be added into
the path gain. This can be achieved with either in line attenuators, or by adding more
cable length.
To determine the amount of loss needed between the modem and the antenna, the
following formula can be used.
Attenuation needed = g – p
where
g = antenna gain (in dB)
g = maximum path gain allowed by FCC based on the modem maximum output power of
+30 dBm, and where p = 3 dB for mobile applications, or p = 7 dB for fixed applications
To determine the proper minimum cable length the following formula can be used.
L = (g – p) / a
where
L = required minimum cable length
g = antenna gain (in dB; per antenna manufacturers specifications).
p = maximum path gain allowed by FCC based on the modem maximum output power of
+30 dBm, p = 3 dB for mobile applications, or p = 7 dB for fixed applications
a = attenuation per foot of cable (in dB; per cable manufacturers specifications).
As long as installation and operating restrictions previously provided are observed, and
antenna gain is limited to 7 dBi for fixed, or 3 dBi for mobile applications, there is no need
to introduce RF loss between the modem and antenna in order to comply with FCC MPE
limits.
NOTE: Cable loss beyond that required to meet the FCC requirements, with the
given antenna, will decrease the signal strength reaching the modem. This will
negatively impact the ability of the modem to communicate with the network.
For more details and guidelines, please see Table 15 and Table 16 and the following
examples.
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FIXED APPLICATIONS
MINIMUM CABLE LENGTH (feet)
ANTENNA
(dBi)
REQUIRED PATH
LOSS (dB)
RG 58
RG 223
RG 8
(0.33 db/ft)
(0.29 db/ft)
(0.15 db/ft)
3.0
3.4
6.7
6.0
6.9
13.3
10
9.0
10.3
20.0
GAIN
Table 15: Cable Loss & Length - Fixed Applications
MOBILE APPLICATIONS
MINIMUM CABLE LENGTH (feet)
ANTENNA
(dBi)
REQUIRED PATH
LOSS (dB)
RG 58
RG 223
RG 8
(0.33 db/ft)
(0.29 db/ft)
(0.15 db/ft)
3.0
3.4
6.7
6.0
6.9
13.3
9.0
10.3
20.0
GAIN
7*
8*
9*
* = not recommended
10*
Table 16: Cable Loss & Length - Mobile Applications
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15.5 Formula Examples
15.5.1 Example 1:
The installer has a nominal 7dB gain antenna, is using RG-223 cable, and is using the
modem in a fixed application.
G = 7 dB
p = 7 dB
a = 0.29 dB/ft
then Attenuation needed = 7 – 7 = 0 dB
and L = (7 – 7) / 0.29 = 0 ft
In this example, the length of cable the installer must use does not matter because he
does not need any loss in the line to meet the FCC requirements.
15.5.2 Example 2:
The installer has a nominal 7 dB gain antenna, is using RG-223 cable, and is using the
modem in a mobile application.
G = 7 dB
p = 3 dB
a = 0.29 dB/ft
then Attenuation needed = 7 – 3 = 4 dB
and L = (7 – 3) / 0.29 = 13.8 ft
In this example, the installer must use at least 13.8 feet of cable or use a 4 dB “in line
attenuator”, or a combination of the two.
15.5.3 Example 3:
The installer has a 10 dB nominal gain antenna, using RG-223 cable, and the modem is in
a fixed application.
G = 10 dB
P = 7 dB
a = 0.29 dB/ft
then Attenuation needed = 10 – 7 = 3 dB
and L = (10 – 7) / 0.29 = 10.3 ft
In this example, the installer must use at least 10.3 feet of cable, or use a 3 dB in line
attenuator, or a combination of the two.
NOTE: The installer is responsible for assuring that the proper antenna, cable
length, and / or attenuation, is installed correctly, so that the limits of FCC §15.203
are not exceeded.
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