Gemalto M2M MC56, MC55 User Manual
MC55/56 Hardware Interface Description
Confidential / Released
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MC55/56
Siemens Cellular Engine
Version: 01.03a
DocID: MC55/56_hid_v01.03a
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Document Name:
Version:
Date:
DocId:
Status:
MC55/56 Hardware Interface Description
01.03a
January 23, 2004
MC55/56_hid_v01.03a
Confidential / Released
General Notes
Product is deemed accepted by recipient and is provided without interface to recipient’s products. The
documentation and/or product are provided for testing, evaluation, integration and information
purposes. The documentation and/or product are provided on an “as is” basis only and may contain
deficiencies or inadequacies. The documentation and/or product are provided without warranty of any
kind, express or implied. To the maximum extent permitted by applicable law, Siemens further
disclaims all warranties, including without limitation any implied warranties of merchantability,
completeness, fitness for a particular purpose and non-infringement of third-party rights. The entire risk
arising out of the use or performance of the product and documentation remains with recipient. This
product is not intended for use in life support appliances, devices or systems where a malfunction of
the product can reasonably be expected to result in personal injury. Applications incorporating the
described product must be designed to be in accordance with the technical specifications provided in
these guidelines. Failure to comply with any of the required procedures can result in malfunctions or
serious discrepancies in results. Furthermore, all safety instructions regarding the use of mobile
technical systems, including GSM products, which also apply to cellular phones must be followed.
Siemens or its suppliers shall, regardless of any legal theory upon which the claim is based, not be
liable for any consequential, incidental, direct, indirect, punitive or other damages whatsoever
(including, without limitation, damages for loss of business profits, business interruption, loss of
business information or data, or other pecuniary loss) arising out the use of or inability to use the
documentation and/or product, even if Siemens has been advised of the possibility of such damages.
The foregoing limitations of liability shall not apply in case of mandatory liability, e.g. under the German
Product Liability Act, in case of intent, gross negligence, injury of life, body or health, or breach of a
condition which goes to the root of the contract. However, claims for damages arising from a breach of
a condition, which goes to the root of the contract, shall be limited to the foreseeable damage, which is
intrinsic to the contract, unless caused by intent or gross negligence or based on liability for injury of
life, body or health. The above provision does not imply a change on the burden of proof to the
detriment of the recipient. Subject to change without notice at any time. The interpretation of this
general note shall be governed and construed according to German law without reference to any other
substantive law.
Copyright
Transmittal, reproduction, dissemination and/or editing of this document as well as utilization of its
contents and communication thereof to others without express authorization are prohibited. Offenders
will be held liable for payment of damages. All rights created by patent grant or registration of a utility
model or design patent are reserved.
Copyright © Siemens AG 2004
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Contents
0 Document History ...................................................................................................... 7
1 Introduction ................................................................................................................ 8
1.1 Related documents ............................................................................................. 8
1.2 Terms and abbreviations..................................................................................... 9
1.3 Type approval ....................................................................................................12
1.4 Safety precautions .............................................................................................14
2 Product concept........................................................................................................16
2.1 MC55/56 key features at a glance......................................................................17
2.2 Circuit concept ...................................................................................................20
3 Application Interface.................................................................................................22
3.1 Operating modes ...............................................................................................23
3.2 Power supply .....................................................................................................25
3.2.1 Power supply pins on the board-to-board connector.............................25
3.2.2 Minimizing power losses.......................................................................26
3.2.3 Monitoring power supply.......................................................................26
3.3 Power up / down scenarios ................................................................................27
3.3.1 Turn on MC55/56 .................................................................................27
3.3.1.1 Turn on MC55/56 using the ignition line /IGT (Power on)..........28
3.3.1.2 Timing of the ignition process ...................................................29
3.3.1.3 Turn on MC55/56 using the POWER signal..............................30
3.3.1.4 Turn on MC55/56 using the RTC (Alarm mode) ........................30
3.3.2 Turn off MC55/56 .................................................................................32
3.3.2.1 Turn off MC55/56 using AT command ......................................32
3.3.2.2 Maximum number of turn-on / turn-off cycles............................32
3.3.2.3 Emergency shutdown using /EMERGOFF pin...........................33
3.3.3 Automatic shutdown .............................................................................34
3.3.3.1 Temperature dependent shutdown............................................34
3.3.3.2 Temperature control during emergency call..............................35
3.3.3.3 Undervoltage shutdown if battery NTC is present .....................35
3.3.3.4 Undervoltage shutdown if no battery NTC is present ................36
3.3.3.5 Overvoltage shutdown ..............................................................36
3.4 Automatic GPRS Multislot Class change............................................................37
3.5 Charging control.................................................................................................38
3.5.1 Battery pack characteristics..................................................................39
3.5.1.1 Recommended battery pack .....................................................40
3.5.2 Implemented charging technique..........................................................41
3.5.3 Operating modes during charging ........................................................42
3.5.4 Charger requirements ..........................................................................43
3.6 Power saving .....................................................................................................44
3.6.1 No power saving (AT+CFUN=1)...........................................................44
3.6.2 NON-CYCLIC SLEEP mode (AT+CFUN=0) .........................................44
3.6.3 CYCLIC SLEEP mode (AT+CFUN=5, 6, 7 and 8) ................................45
3.6.4 Timing of the /CTS signal in CYCLIC SLEEP modes ...........................45
3.6.5 Wake up MC55/56 from SLEEP mode .................................................47
3.7 Summary of state transitions (except SLEEP mode)..........................................48
3.8 RTC backup.......................................................................................................49
3.9 Serial interfaces .................................................................................................50
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3.9.1 Features supported on first and second serial interface .......................51
3.10 Audio interfaces .................................................................................................53
3.10.1 Microphone circuit ................................................................................54
3.10.2 Speech processing...............................................................................55
3.10.3 DAI timing.............................................................................................55
3.11 SIM interface......................................................................................................57
3.11.1 Requirements for using the CCIN pin ...................................................58
3.11.2 Design considerations for SIM card holder...........................................59
3.12 Control signals ...................................................................................................60
3.12.1 Inputs ...................................................................................................60
3.12.2 Outputs.................................................................................................61
3.12.2.1 Synchronization signal.........................................................61
3.12.2.2 Using the SYNC pin to control a status LED........................62
3.12.2.3 Behaviour of the /RING0 line (ASC0 interface only).............63
4 Antenna interface......................................................................................................64
4.1 Antenna installation............................................................................................64
4.1.1 Antenna pad.........................................................................................66
4.1.1.1 Suitable cable types..................................................................66
4.1.2 Hirose antenna connector ....................................................................67
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5 Electrical, reliability and radio characteristics .......................................................71
5.1 Absolute maximum ratings.................................................................................71
5.2 Operating temperatures .....................................................................................71
5.3 Electrical specifications of the application interface............................................72
5.4 Power supply ratings..........................................................................................76
5.4.1 Current consumption during transmit burst...........................................77
Electrical characteristics of the voiceband part............................................................82
5.4.2 Setting audio parameters by AT commands.........................................82
5.4.3 Audio programming model ...................................................................83
5.4.4 Characteristics of audio modes ............................................................84
5.4.5 Voiceband receive path ........................................................................85
5.4.6 Voiceband transmit path.......................................................................86
5.5 Air interface........................................................................................................87
5.6 Electrostatic discharge.......................................................................................88
5.7 Reliability characteristics ....................................................................................89
6 Mechanics..................................................................................................................90
6.1 Mechanical dimensions of MC55/56...................................................................90
6.2 Mounting MC55/56 onto the application platform ...............................................92
6.3 Board-to-board connector ..................................................................................93
6.3.1 Mechanical dimensions of the Hirose DF12 connector .........................94
6.3.2 Adapter cabling ....................................................................................94
6.4 Heat sinks and thermally conductive tapes ........................................................95
6.4.1 Test conditions and results...................................................................95
7 Reference Approval ..................................................................................................97
7.1 Reference Equipment for Type Approval ...........................................................97
7.2 Compliance with FCC Rules and Regulations (MC55 only)................................98
7.3 Compliance with FCC Rules and Regulations (MC56 only)................................99
8 List of parts and accessories.................................................................................100
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Figures
Figure 1: MC55/56 block diagram ........................................................................................21
Figure 2: Power supply limits during transmit burst ..............................................................26
Figure 3: Power-on by ignition signal....................................................................................28
Figure 4: Timing of power-on process if VDDLP is not used ................................................29
Figure 5: Timing of power-on process if VDDLP is fed from external source........................29
Figure 6: Deactivating GSM engine by /EMERGOFF signal.................................................33
Figure 7: Schematic of approved charging transistor, trickle charging and ESD protection ..38
Figure 8: Battery pack circuit diagram ..................................................................................39
Figure 9: Charging process..................................................................................................41
Figure 10: Timing of /CTS signal (example for a 2.12 s paging cycle)..................................46
Figure 11: Beginning of power saving if CFUN=5 or 7..........................................................46
Figure 12: RTC supply from capacitor..................................................................................49
Figure 13: RTC supply from rechargeable battery................................................................49
Figure 14: RTC supply from non-chargeable battery............................................................49
Figure 15: Serial interfaces ..................................................................................................50
Figure 16: Audio block diagram............................................................................................53
Figure 17: Schematic of microphone inputs .........................................................................54
Figure 18: DAI timing on transmit path .................................................................................56
Figure 19: DAI timing on receive path ..................................................................................56
Figure 20: SIM card holder of DSB45 Support Box ..............................................................59
Figure 21: Pin numbers of Molex SIM card holder on DSB45 Support Box ..........................59
Figure 22: SYNC signal during transmit burst ......................................................................61
Figure 23: LED Circuit (Example).........................................................................................62
Figure 24: Incoming voice call..............................................................................................63
Figure 25: Incoming data call ...............................................................................................63
Figure 26: URC transmission ...............................................................................................63
Figure 27: U.FL-R-SMT connector .......................................................................................64
Figure 28: Antenna pad and GND plane ..............................................................................64
Figure 29: Never use antenna connector and antenna pad at the same time.......................65
Figure 30: Restricted area around antenna pad ...................................................................65
Figure 31: Mechanical dimensions of U.FL-R-SMT connector..............................................67
Figure 32: U.FL-R-SMT connector with U.FL-LP-040 plug ...................................................68
Figure 33: U.FL-R-SMT connector with U.FL-LP-066 plug ...................................................68
Figure 34: Specifications of U.FL-LP-(V)-040(01) plug.........................................................69
Figure 35: Pin assignment (top view on MC55)....................................................................72
Figure 36: Typical current consumption vs. power control level............................................80
Figure 37: Typical current consumption vs. return loss.........................................................81
Figure 38: AT audio programming model .............................................................................83
Figure 39: MC55/56 – top view.............................................................................................90
Figure 40: Mechanical dimensions of MC55/56....................................................................91
Figure 41: MC55/56 bottom view..........................................................................................92
Figure 42: Hirose DF12C receptacle on MC55/56................................................................93
Figure 43: Header Hirose DF12 series.................................................................................93
Figure 44: Mechanical dimensions of Hirose DF12 connector..............................................94
Figure 45: Reference equipment for approval ......................................................................97
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Tables
Table 1: MC55/56 key features ............................................................................................17
Table 2: Coding schemes and maximum net data rates over air interface ...........................19
Table 3: Overview of operating modes.................................................................................23
Table 4: Power supply pins of board-to-board connector .....................................................25
Table 5: AT commands available in Alarm mode .................................................................30
Table 6: Temperature dependent behaviour.........................................................................35
Table 7: Bill of material for external charging circuit .............................................................38
Table 8: Specifications of XWODA battery pack ..................................................................40
Table 9: Comparison Charge-only and Charge mode ..........................................................42
Table 10: AT commands available in Charge-only mode......................................................43
Table 11: Wake-up events in NON-CYCLIC and CYCLIC SLEEP modes............................47
Table 12: State transitions of MC55/56 (except SLEEP mode) ............................................48
Table 13: DCE-DTE wiring of 1st serial interface .................................................................51
Table 14: DCE-DTE wiring of 2nd serial interface ................................................................52
Table 15: Signals of the SIM interface (board-to-board connector) ......................................57
Table 16: Pin assignment of Molex SIM card holder on DSB45 Support Box .......................59
Table 17: Input control signals of the MC55/56 module........................................................60
Table 18: MC55/56 synchronization signal (if SYNC pin is set to mode 0 via AT^SSYNC)...61
Table 19: Coding of the status LED......................................................................................62
Table 20: MC55/56 ring signal..............................................................................................63
Table 21: Return loss ...........................................................................................................64
Table 22: Product specifications of U.FL-R-SMT connector .................................................67
Table 23: Material and finish of U.FL-R-SMT connector and recommended plugs...............68
Table 24: Ordering information for Hirose U.FL Series.........................................................70
Table 25: Absolute maximum ratings ...................................................................................71
Table 26: Operating temperatures........................................................................................71
Table 27: Electrical description of application interface ........................................................73
Table 28: Power supply ratings ............................................................................................76
Table 29: Audio parameters adjustable by AT command .....................................................82
Table 30: Voiceband characteristics (typical) .......................................................................84
Table 31: Voiceband receive path ........................................................................................85
Table 32: Voiceband transmit path.......................................................................................86
Table 33: Air Interface..........................................................................................................87
Table 34: Measured electrostatic values ..............................................................................88
Table 35: Summary of reliability test conditions....................................................................89
Table 36: Ordering information DF12 series.........................................................................93
Table 37: Electrical and mechanical characteristics of the Hirose DF12C connector............93
Table 38: Tested heat sinks and thermally conductive tapes and test results ......................96
Table 39: List of parts and accessories ..............................................................................100
Table 40: Molex sales contacts (subject to change) ........................................................... 101
Table 41: Hirose sales contacts (subject to change) .......................................................... 101
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0 Document History
Preceding document: "MC55/56 Hardware Interface Description" Version 01.03
New document: "MC55/56 Hardware Interface Description" Version 01.03a
Chapter Page What is new
7.2, 7.3 98, 99 Corrected MC55 and MC56 specific information on FFC compliance
Preceding document: "MC55/56 Hardware Interface Description" Version 01.02
New document: "MC55/56 Hardware Interface Description" Version 01.03
Chapter Page What is new
1.3 12 Note on necessary FCC certification added.
Updated document: "MC55/56 Hardware Interface Description" Version 01.02
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1 Introduction
This document describes the hardware interface of the Siemens MC55/56 module that
connects to the cellular device application and the air interface. As MC55/56 is intended to
integrate with a wide range of application platforms, all functional components are described
in great detail.
This guide therefore covers all information needed to design and set up cellular applications
incorporating the MC55/56 module. It aids rapid retrieval of interface specifications, electrical
and mechanical details and information on the requirements to be considered for integration
of further components.
1.1 Related documents
[1] MC55/56 AT Command, Version 01.02
[2] MC55/56 Release Notes, Version 01.02
[3] GPRS Startup User's Guide
[4] Remote-SAT User's Guide
[5] DSB45 Support Box - Evaluation Kit for Siemens Cellular Engines
[6] Application Note 23: Installing MC55/56 on DSB45
[7] Application Note 16: Upgrading MC45 Firmware, Version 0.5
[8] Application Note 14: Audio and Battery Parameter Download
[9] Application Note 02: Audio Interface Design
[10] Multiplexer User's Guide
[11] Multiplex Driver Developer’s Guide for Windows 2000 and Windows XP
[12] Multiplex Driver Installation Guide for Windows 2000 and Windows XP
[13] Application Note 22: Using TTY / CTM equipment with MC45
[14] Application Note 24: Application Developer’s Guide
Prior to using the MC55/56 engines or upgrading to a new firmware release, be sure to
carefully read the latest product information.
To visit the Siemens Website you can use the following link:
http://www.siemens.com/wm
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1.2 Terms and abbreviations
Abbreviation Description
ADC Analog-to-Digital Converter
AFC Automatic Frequency Control
AGC Automatic Gain Control
ANSI American National Standards Institute
ARFCN Absolute Radio Frequency Channel Number
ARP Antenna Reference Point
ASC0 / ASC1 Asynchronous Controller. Abbreviations used for first and second serial interface of
MC55/56
ASIC Application Specific Integrated Circuit
B Thermistor Constant
B2B Board-to-board connector
BER Bit Error Rate
BTS Base Transceiver Station
CB or CBM Cell Broadcast Message
CE Conformité Européene (European Conformity)
CHAP Challenge Handshake Authentication Protocol
CPU Central Processing Unit
CS Coding Scheme
CSD Circuit Switched Data
CTS Clear to Send
DAC Digital-to-Analog Converter
DAI Digital Audio Interface
dBm0 Digital level, 3.14dBm0 corresponds to full scale, see ITU G.711, A-law
DCE Data Communication Equipment (typically modems, e.g. Siemens GSM engine)
DCS 1800 Digital Cellular System, also referred to as PCN
DRX Discontinuous Reception
DSB Development Support Box
DSP Digital Signal Processor
DSR Data Set Ready
DTE Data Terminal Equipment (typically computer, terminal, printer or, for example, GSM
application)
DTR Data Terminal Ready
DTX Discontinuous Transmission
EFR Enhanced Full Rate
EGSM Enhanced GSM
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Abbreviation Description
EMC Electromagnetic Compatibility
ESD Electrostatic Discharge
ETS European Telecommunication Standard
FCC Federal Communications Commission (U.S.)
FDMA Frequency Division Multiple Access
FR Full Rate
GMSK Gaussian Minimum Shift Keying
GPRS General Packet Radio Service
GSM Global Standard for Mobile Communications
HiZ High Impedance
HR Half Rate
I/O Input/Output
IC Integrated Circuit
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IMEI International Mobile Equipment Identity
ISO International Standards Organization
ITU International Telecommunications Union
kbps kbits per second
LED Light Emitting Diode
Li-Ion Lithium-Ion
Mbps Mbits per second
MMI Man Machine Interface
MO Mobile Originated
MS Mobile Station (GSM engine), also referred to as TE
MSISDN Mobile Station International ISDN number
MT Mobile Terminated
NTC Negative Temperature Coefficient
OEM Original Equipment Manufacturer
PA Power Amplifier
PAP Password Authentication Protocol
PBCCH Packet Switched Broadcast Control Channel
PCB Printed Circuit Board
PCL Power Control Level
PCM Pulse Code Modulation
PCN Personal Communications Network, also referred to as DCS 1800
PCS Personal Communication System, also referred to as GSM 1900
PDU Protocol Data Unit
PLL Phase Locked Loop
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Abbreviation Description
PPP Point-to-point protocol
PSU Power Supply Unit
R&TTE Radio and Telecommunication Terminal Equipment
RAM Random Access Memory
RF Radio Frequency
RMS Root Mean Square (value)
ROM Read-only Memory
RTC Real Time Clock
Rx Receive Direction
SAR Specific Absorption Rate
SELV Safety Extra Low Voltage
SIM Subscriber Identification Module
SMS Short Message Service
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SRAM Static Random Access Memory
TA Terminal adapter (e.g. GSM engine)
TDMA Time Division Multiple Access
TE Terminal Equipment, also referred to as DTE
Tx Transmit Direction
UART Universal asynchronous receiver-transmitter
URC Unsolicited Result Code
USSD Unstructured Supplementary Service Data
VSWR Voltage Standing Wave Ratio
Phonebook abbreviations
FD SIM fixdialing phonebook
LD SIM last dialling phonebook (list of numbers most recently dialled)
MC Mobile Equipment list of unanswered MT calls (missed calls)
ME Mobile Equipment phonebook
ON Own numbers (MSISDNs) stored on SIM or ME
RC Mobile Equipment list of received calls
SM SIM phonebook
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1.3 Type approval
MC55/56 is designed to comply with the directives and standards listed below. Please
note that the product is still in a pre-release state and, therefore, type approval and
testing procedures have not yet been completed.
European directives
99/05/EC “Directive of the European Parliament and of the council of 9 March
1999 on radio equipment and telecommunications terminal
equipment and the mutual recognition of their conformity”, in short
referred to as R&TTE Directive 1999/5/EC
89/336/EC Directive on electromagnetic compatibility
73/23/EC Directive on electrical equipment designed for use within certain
voltage limits (Low Voltage Directive)
Standards of North American Type Approval
CFR Title 47 “Code of Federal Regulations, Part 2 and Part 24
(Telecommunications, PCS)”
US Equipment Authorization FCC
UL 60 950 “Product Safety Certification” (Safety requirements)
NAPRD.3 “Overview of PCS Type certification review board
Mobile Equipment Type Certification and IMEI control”
PCS Type Certification Review board (PTCRB)
Standards of European Type Approval
3GPP TS 51.010-1 “Digital cellular telecommunications system (Phase 2); Mobile
Station (MS) conformance specification”.
ETSI EN 301 511 “V7.0.1 (2000-12) Candidate Harmonized European Standard
(Telecommunications series) Global System for Mobile
communications (GSM); Harmonized standard for mobile stations in
the GSM 900 and DCS 1800 bands covering essential requirements
under article 3.2 of the R&TTE directive (1999/5/EC) (GSM 13.11
version 7.0.1 Release 1998)”
GCF-CC “Global Certification Forum - Certification Criteria”
ETSI EN 301 489-1 “V1.1.1 (2000-09) Candidate Harmonized European Standard
(Telecommunications series) Electro Magnetic Compatibility and
Radio spectrum Matters (ERM); Electro Magnetic Compatibility
(EMC) standard for radio equipment and services; Part 1: Common
Technical Requirements”
ETSI EN 301 489-7 “V1.1.1 (2000-09) Candidate Harmonized European Standard
(Telecommunications series) Electro Magnetic Compatibility and
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Radio spectrum Matters (ERM); Electro Magnetic Compatibility
(EMC) standard for radio equipment and services; Part 7: Specific
conditions for mobile and portable radio and ancillary equipment of
digital cellular radio telecommunications systems (GSM and DCS)”
EN 60 950 Safety of information technology equipment (2000)
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Requirements of quality
IEC 60068 Environmental testing
DIN EN 60529 IP codes
Compliance with international rules and regulations
Manufacturers of mobile or fixed devices incorporating MC55/56 modules are advised to
have their completed product tested and approved for compliance with all applicable national
and international regulations. As a tri-band GSM/GPRS engine designed for use on any
GSM network in the world, MC55/56 is required to pass all approvals relevant to operation
on the European and North American markets. For the North American market this includes
the Rules and Regulations of the Federal Communications Commission (FCC) and PTCRB,
for the European market the R&TTE Directives and GCF Certification Criteria must be fully
satisfied.
The FCC Equipment Authorization granted to the MC55/56 Siemens reference application is
valid only for the equipment described in Chapter 7.
SAR requirements specific to handheld mobiles
Mobile phones, PDAs or other handheld transmitters and receivers incorporating a GSM
module must be in accordance with the guidelines for human exposure to radio frequency
energy. This requires the Specific Absorption Rate (SAR) of handheld MC55/56 based
applications to be evaluated and approved for compliance with national and/or international
regulations.
Since the SAR value varies significantly with the individual product design manufacturers are
advised to submit their product for approval if designed for handheld operation. For
European and US markets the relevant directives are mentioned below. It is the
responsibility of the manufacturer of the final product to verify whether or not further
standards, recommendations of directives are in force outside these areas.
Products intended for sale on US markets
ES 59005/ANSI C95.1 Considerations for evaluation of human exposure to
Electromagnetic Fields (EMFs) from Mobile Telecommunication
Equipment (MTE) in the frequency range 30MHz-6GHz
Products intended for sale on European markets
EN 50360 Product standard to demonstrate the compliance of mobile phones
with the basic restrictions related to human exposure to
electromagnetic fields (300 MHz - 3 GHz)
Note: Usage of MC55/56 in a handheld or portable application is not allowed without a
new FCC certification.
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1.4 Safety precautions
The following safety precautions must be observed during all phases of the operation,
usage, service or repair of any cellular terminal or mobile incorporating MC55/56.
Manufacturers of the cellular terminal are advised to convey the following safety information
to users and operating personnel and to incorporate these guidelines into all manuals
supplied with the product. Failure to comply with these precautions violates safety standards
of design, manufacture and intended use of the product. Siemens AG assumes no liability
for customer failure to comply with these precautions.
When in a hospital or other health care facility, observe the restrictions on the
use of mobiles. Switch the cellular terminal or mobile off, if instructed to do so
by the guidelines posted in sensitive areas. Medical equipment may be
sensitive to RF energy.
The operation of cardiac pacemakers, other implanted medical equipment
and hearing aids can be affected by interference from cellular terminals or
mobiles placed close to the device. If in doubt about potential danger, contact
the physician or the manufacturer of the device to verify that the equipment is
properly shielded. Pacemaker patients are advised to keep their hand-held
mobile away from the pacemaker, while it is on.
Switch off the cellular terminal or mobile before boarding an aircraft. Make
sure it cannot be switched on inadvertently. The operation of wireless
appliances in an aircraft is forbidden to prevent interference with
communications systems. Failure to observe these instructions may lead to
the suspension or denial of cellular services to the offender, legal action, or
both.
Do not operate the cellular terminal or mobile in the presence of flammable
gases or fumes. Switch off the cellular terminal when you are near petrol
stations, fuel depots, chemical plants or where blasting operations are in
progress. Operation of any electrical equipment in potentially explosive
atmospheres can constitute a safety hazard.
Your cellular terminal or mobile receives and transmits radio frequency
energy while switched on. Remember that interference can occur if it is used
close to TV sets, radios, computers or inadequately shielded equipment.
Follow any special regulations and always switch off the cellular terminal or
mobile wherever forbidden, or when you suspect that it may cause
interference or danger.
Road safety comes first! Do not use a hand-held cellular terminal or mobile
when driving a vehicle, unless it is securely mounted in a holder for handsfree
operation. Before making a call with a hand-held terminal or mobile, park the
vehicle.
Handsfree devices must be installed by qualified personnel. Faulty installation
or operation can constitute a safety hazard.
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IMPORTANT!
SOS
Cellular terminals or mobiles operate using radio signals and cellular
networks cannot be guaranteed to connect in all conditions. Therefore, you
should never rely solely upon any wireless device for essential
communications, for example emergency calls.
Remember, in order to make or receive calls, the cellular terminal or mobile
must be switched on and in a service area with adequate cellular signal
strength.
Some networks do not allow for emergency calls if certain network services
or phone features are in use (e.g. lock functions, fixed dialling etc.). You may
need to deactivate those features before you can make an emergency call.
Some networks require that a valid SIM card be properly inserted in the
cellular terminal or mobile.
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2 Product concept
Designed for use on any GSM network in the world, Siemens MC55 is a tri-band GSM/GPRS
engine that works on the three frequencies GSM 900 MHz, GSM 1800 MHz and GSM
1900 MHz. MC56 is a tri-band GSM/GPRS engine that works on the three frequencies GSM
850MHz, GSM 1800 MHz and GSM 1900 MHz. MC55/56 features GPRS multislot class 10
and supports the GPRS coding schemes CS-1, CS-2, CS-3 and CS-4.
To save space on the application platform, MC55/56 comes as an extremely slim and
compact module. This makes it ideally suited for a broad range of mobile computing devices,
and particularly offers easy integration with smart phones, PDAs, and other handhelds.
The tiny MC55/56 module incorporates all you need to create high-performance GSM/GPRS
solutions: baseband processor, power supply ASIC, complete radio frequency circuit
including a power amplifier and antenna interface. The power amplifier is directly fed from
the supply voltage BATT+. A compact “stacked FLASH / SRAM” device stores the MC55/56
software in the flash memory section, and static RAM section provides the additional storage
capacity required by GPRS connectivity.
The physical interface to the cellular application is made through a board-to-board
connector. It consists of 50 pins, required for controlling the unit, transferring data and audio
signals and providing power supply lines.
MC55/56 comprises two serial interfaces (ASC0 and ASC1) giving you maximum flexibility
for easy integration with the Man-Machine Interface (MMI).
An extremely versatile audio concept offers various audio interfaces, each available on the
board-to-board connector: a digital audio interface (DAI) and two analog audio interfaces.
Using AT commands you can easily switch back and forth and select different audio modes.
The external dual-band or triple-band antenna can be connected optionally to a connector on
the top side or to a pad on the bottom side.
The power saving technique minimizes current consumption to as low as 3mA. In SLEEP
mode, MC55/56 is able to wake up on demand and to resume power saving automatically if
no activity is required.
For battery powered applications, MC55/56 features a charging control which can be used to
charge a Li-Ion battery. The charging circuit must be implemented outside the module on the
application platform.
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2.1 MC55/56 key features at a glance
Table 1: MC55/56 key features
Feature Implementation
Power supply Single supply voltage 3.3V – 4.8V
Power saving Minimizes power consumption in SLEEP mode to 3mA
Charging Supports charging control for Li-Ion battery
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Frequency bands
GSM class Small MS
Transmit power
GPRS connectivity
Temperature range
Temperature control
and auto switch-off
DATA GPRS:
CSD:
WAP:
· MC55 Tri-band: EGSM 900, GSM 1800, GSM 1900
· MC56 Tri-band: GSM 850, GSM 1800, GSM 1900
· Compliant to GSM Phase 2/2+
· Class 4 (2W) at EGSM900 and GSM850
· Class 1 (1W) at GSM1800 and GSM 1900
· GPRS multi-slot class 10
· GPRS mobile station class B
· Normal operation: -20°C to +55°C
· Restricted operation: -25°C to -20°C and +55°C to +65°C
· Constant temperature control prevents damage to MC55/56 when the
specified temperature is exceeded. When an emergency call is in
progress the automatic temperature shutdown functionality is
deactivated.
· GPRS data downlink transfer: max. 85.6 kbps (see Table 2)
· GPRS data uplink transfer: max. 42.8 kbps (see Table 2)
· Coding scheme: CS-1, CS-2, CS-3 and CS-4
· MC55/56 supports the two protocols PAP (Password Authentication
Protocol) and CHAP (Challenge Handshake Authentication Protocol)
commonly used for PPP connections.
· Support of Packet Switched Broadcast Control Channel (PBCCH) allows
you to benefit from enhanced GPRS performance when offered by the
network operators.
· CSD transmission rates: 2.4, 4.8, 9.6, 14.4 kbps, non-transparent, V.110
· Unstructured Supplementary Services Data (USSD) support
· WAP compliant
SMS
MMS MMS compliant
FAX Group 3: Class 1, Class 2
SIM interface
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· MT, MO, CB, Text and PDU mode
· SMS storage: SIM card plus 25 SMS locations in the mobile equipment
· Transmission of SMS alternatively over CSD or GPRS. Preferred mode
can be user-defined.
· Supported SIM card: 3V
· External SIM card reader has to be connected via interface connector
(note that card reader is not part of MC55/56)
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Feature Implementation
External antenna Connected via 50 Ohm antenna connector or antenna pad
Audio interfaces Two analog audio interfaces, one digital audio interface (DAI)
Audio features Speech codec modes:
· Half Rate (ETS 06.20)
· Full Rate (ETS 06.10)
· Enhanced Full Rate (ETS 06.50 / 06.60 / 06.80)
· Adaptive Multi Rate (AMR)
Handsfree operation
· Echo cancellation
· Noise reduction
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Two serial interfaces:
ASC0, ASC1
Phonebook
management
SIM Application Toolkit Supports SAT class 3, GSM 11.14 Release 98
Ringing tones Offers a choice of 7 different ringing tones / melodies, easily selectable with
Real time clock Implemented
Timer function Programmable via AT command
Support of TTY/CTM To benefit from TTY communication via GSM, CTM equipment can be
Physical characteristics Size: 35+0.15 x 32.5+0.15 x 3.1+0.3 mm (including application
· 2.65V level, bi-directional bus for AT commands and data
· ASC0 – full-featured 8-wire serial interface. Supports RTS0/CTS0
hardware handshake and software XON/XOFF flow control. Multiplex
ability according to GSM 07.10 Multiplexer Protocol.
· ASC1 - 4-wire serial interface. Supports RTS1/CTS1 hardware
handshake and software XON/XOFF flow control.
· Baud rate: 300bps ... 230kbps on ASC0 and ASC1
· Autobauding (on ASC0 only) detects 1200, 2400, 4800, 9600, 19200,
38400, 57600, 115200, 230400 bps
Supported phonebook types: SM, FD, LD, MC, RC, ON, ME
AT command
connected to one of the three audio interfaces.
connector)
35+0.15 x 32.5+0.15 x 2.8+0.2 mm (excluding
application connector)
Weight: 5.5g
Firmware upgrade Firmware upgradable over serial interface and SIM interface
Evaluation kit The DSB45 Support Box is an evaluation kit designed to test and type
approve Siemens cellular engines and provide a sample configuration for
application engineering. See Chapter 8 for ordering information.
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Table 2: Coding schemes and maximum net data rates over air interface
Coding scheme 1 Timeslot 2 Timeslots 4 Timeslots
CS-1: 9.05 kbps 18.1 kbps 36.2 kbps
CS-2: 13.4 kbps 26.8 kbps 53.6 kbps
CS-3: 15.6 kbps 31.2 kbps 62.4 kbps
CS-4: 21.4 kbps 42.8 kbps 85.6 kbps
Please note that the values stated above are maximum ratings which, in practice, are influenced by a
great variety of factors, primarily, for example, traffic variations and network coverage.
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2.2 Circuit concept
Figure 1 shows a block diagram of the MC55/56 module and illustrates the major functional
components:
GSM / GPRS baseband block:
· Baseband controller operating at 26MHz
· Power supply ASIC
· Stacked Flash / SRAM
· Application interface (board-to-board connector)
GSM RF block:
· Skyworks RF transceiver
· Skyworks RF power amplifier / FEM
· RF front end (antenna connector)
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SKY77500 PA / FEM
RX PCS
RX GSM
SKY74963 Transceiver
26.0
MHz
BS2
SIM I/O
TX_RX
PAC_EN
RX DCS
TX GSM
TX DCS/PCS
RXI/Q
4
TXI/Q
4
RFCTRL
3
26MHz
PMB7850 Controller
6
4
4
ASC08
4ASC1
Network
Measuring
DAI5
EPP
MIC
BATTTEMP
CCVCC
CCIN
4
SIM
BATT-TEMP
Add. / Data / Control
Stacked FLASH / SRAM
Application Interface
VDD_LP
LOWVDD
/IGT
/EMERGOFF
DO767BA Power Supply ASIC
CHARGE
BATT+
POWERPOWER
BATT+
GND
Ext.
Charging
Circuit
NTC
Figure 1: MC55/56 block diagram
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3 Application Interface
MC55/56 is equipped with a 50-pin 0.5mm pitch board-to-board connector that connects to
the cellular application platform. The host interface incorporates several sub-interfaces
described in the following chapters:
· Power supply and charging control (see Chapters 3.2 and 3.3)
· Dual serial interface (see Chapter 3.9)
· Two analog audio interfaces and a digital audio interface (see Chapter 3.10)
· SIM interface (see Chapter 3.11)
Electrical and mechanical characteristics of the board-to-board connector are specified in
Chapter 6.3. Ordering information for mating connectors and cables are included.
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3.1 Operating modes
The table below briefly summarizes the various operating modes referred to in the following
chapters.
Table 3: Overview of operating modes
Mode Function
Normal operation
GSM / GPRS SLEEP Various powersave modes set with AT+CFUN
command.
Software is active to minimum extent. If the module was
registered to the GSM network in IDLE mode, it is
registered and paging with the BTS in SLEEP mode,
too. Power saving can be chosen at different levels: The
NON-CYCLIC SLEEP mode (AT+CFUN=0) disables the
AT interface. The CYCLIC SLEEP modes AT+CFUN=5,
6, 7 and 8 alternatively activate and deactivate the AT
interfaces to allow permanent access to all AT
commands.
GSM IDLE Software is active. Once registered to the GSM network,
paging with BTS is carried out. The module is ready to
send and receive.
GSM TALK Connection between two subscribers is in progress.
Power consumption depends on network coverage
individual settings, such as DTX off/on, FR/EFR/HR,
hopping sequences, antenna.
GPRS IDLE Module is ready for GPRS data transfer, but no data is
currently sent or received. Power consumption depends
on network settings and GPRS configuration (e.g.
multislot settings).
GPRS DATA GPRS data transfer in progress. Power consumption
depends on network settings (e.g. power control level),
uplink / downlink data rates and GPRS configuration
(e.g. used multislot settings).
POWER DOWN Normal shutdown after sending the AT^SMSO command.
The Power Supply ASIC (PSU-ASIC) disconnects the supply voltage from the
baseband part of the circuit. Only a voltage regulator in the PSU-ASIC is active
for powering the RTC. Software is not active. The serial interfaces are not
accessible.
Operating voltage (connected to BATT+) remains applied.
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Mode Function
Alarm mode Restricted operation launched by RTC alert function while the module is in
POWER DOWN mode. Module will not be registered to GSM network. Limited
number of AT commands is accessible.
If application is battery powered: No charging functionality in Alarm mode.
Charge-only mode Limited operation for battery powered applications. Enables charging while
module is detached from GSM network. Limited number of AT commands is
accessible. There are several ways to launch Charge-only mode:
· From POWER DOWN mode: Connect charger to the charger input pin of the
external charging circuit and the module’s POWER pin when MC55/56 was
powered down by AT^SMSO.
· From Normal mode: Connect charger to the charger input pin of the external
charging circuit and the module’s POWER pin, then enter AT^SMSO.
Charge mode
during normal
operation
Normal operation (SLEEP, IDLE, TALK, GPRS IDLE, GPRS DATA) and
charging running in parallel. Charge mode changes to Charge-only mode when
the module is powered down before charging has been completed.
See Table 11 and Table 12 for the various options of waking up MC55/56 and proceeding from one
mode to another.
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3.2 Power supply
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The power supply of MC55/56 has to be a single voltage source of V
= 3.3V...4.8V. It
BATT+
must be able to provide sufficient current in a transmit burst which typically rises to 2A.
Beyond that, the power supply must be able to account for increased current consumption if
the module is exposed to inappropriate conditions, for example antenna mismatch. For
further details see Chapters 3.2.2 and 5.4.1.
All the key functions for supplying power to the device are handled by an ASIC power
supply. The ASIC provides the following features:
· Stabilizes the supply voltages for the GSM baseband using low drop linear voltage
regulators.
· Controls the module's power up and power down procedures.
A watchdog logic implemented in the baseband processor periodically sends signals to
the ASIC, allowing it to maintain the supply voltage for all digital MC55/56 components.
Whenever the watchdog pulses fail to arrive constantly, the module is turned off.
· Delivers, across the VDD pin, a regulated voltage of 2.9V. The output voltage VDD may
be used to supply, for example, an external LED or a level shifter. However, the external
circuitry must not cause any spikes or glitches on voltage VDD. This voltage is not
available in POWER DOWN mode. Therefore, the VDD pin can be used to indicate
whether or not MC55/56 is in POWER DOWN mode.
· Provides power to the SIM interface.
The RF power amplifier is driven directly from BATT+.
3.2.1 Power supply pins on the board-to-board connector
Five BATT+ pins of the board-to-board connector are dedicated to connect the supply
voltage, five GND pins are recommended for grounding. The values stated below must be
measured directly at the reference points on the MC55/56 board (TP BATT+ and TP GND
illustrated in Figure 41).
The POWER and CHARGE pins serve as control signals for charging a Li-Ion battery.
VDDLP can be used to back up the RTC.
Table 4: Power supply pins of board-to-board connector
Signal name I/O Description Parameter
BATT+ I/O Positive operating voltage
Reference points are the
test points
GND - Ground 0 V
POWER I This line signals to the
processor that the charger
is connected.
CHARGE O Control signal for external
charging transistor
VDDLP I/O Can be used to back up the
RTC when V
applied.
See Chapter 3.8
BATT+
is not
3.3 V...4.8 V, I
The minimum operating voltage must not fall
below 3.3 V, not even in case of voltage drop.
U
UIN = 2.0 V...5.5 V
Ri = 1kW
I
in,max
OUT,max
= 30µA
< V
£ 2 A during transmit burst
typ
BATT+
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3.2.2 Minimizing power losses
When designing the power supply for your application please pay specific attention to power
losses. Ensure that the input voltage V
not even in a transmit burst where current consumption can rise to typical peaks of 2A. Any
voltage drops that may occur in a transmit burst should not exceed 400mV. It should be
noted that MC55/56 switches off when exceeding these limits. For further details see
Chapter 5.4.
The best approach to reducing voltage drops is to use a board-to-board connection as
recommended, and a low impedance power source. The resistance of the power supply lines
on the host board and of a battery pack should also be considered.
Note: If the application design requires an adapter cable between both board-to-board
connectors, use a flex cable as short as possible in order to minimize power
losses.
Example: If the length of the flex cable reaches the maximum length of 200mm, this
connection may cause, for example, a resistance of 50m! in the BATT+ line and
50m! in the GND line. As a result, a 2A transmit burst would add up to a total
voltage drop of 200mV. Plus, if a battery pack is involved, further losses may
occur due to the resistance across the battery lines and the internal resistance of
the battery.
never drops below 3.3 V on the MC55/56 board,
BATT+
Figure 2: Power supply limits during transmit burst
The input voltage V
(TP BATT+ and TP GND illustrated in Figure 41).
must be measured directly at the test points on the MC55/56 board
BATT+
3.2.3 Monitoring power supply
To help you monitor the supply voltage you can use the AT^SBV command which returns the
voltage measured at TP BATT+ and GND.
The voltage is continuously measured at intervals depending on the operating mode on the
RF interface. The duration of measuring ranges from 0.5s in TALK/DATA mode to 50s when
MC55/56 is deregistered. The displayed voltage (in mV) is averaged over the last measuring
period before the AT^SBV command was executed.
For details please refer to [1].
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3.3 Power up / down scenarios
In general, be sure not to turn on MC55/56 while it is out of the operating range of voltage
and temperature stated in Chapters 5.2 and 5.3. MC55/56 would immediately switch off after
having started and detected these inappropriate conditions.
3.3.1 Turn on MC55/56
MC55/56 can be activated in a variety of ways, which are described in the following chapters:
· via ignition line /IGT: starts normal operating state (see Chapters 3.3.1.1 and 3.3.1.2)
· via POWER line: starts charging algorithm (see Chapters 3.5.3 and 3.3.1.3)
· via RTC interrupt: starts Alarm mode (see Chapter 3.3.1.4)
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3.3.1.1 Turn on MC55/56 using the ignition line /IGT (Power on)
To switch on MC55/56 the /IGT (Ignition) signal needs to be driven to ground level for at
least 100ms and not earlier than 10ms after the last falling edge of VDD. This can be
accomplished using an open drain/collector driver in order to avoid current flowing into this
pin.
BATT+
min. 10ms
min.
/IGT
HiZ
ca. 60ms
100ms
HiZ
VDD
/TXD0
/TXD1
/DSR0
/EMERGOFF
Serial interfaces
ASC0 and ASC1
For details please see Chapter 3.3.1.2
Software
controlled
Undefined
ca. 300ms ca. 900ms
Inactive
Active
Figure 3: Power-on by ignition signal
If configured to a fix baud rate, MC55/56 will send the result code ^SYSSTART to indicate
that it is ready to operate. This result code does not appear when autobauding is active. See
Chapter AT+IPR in [1].
In a battery operated MC55/56 application, the duration of the /IGT signal must be 1s
minimum when the charger is connected and you may want to go from charging to Normal
mode.
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3.3.1.2 Timing of the ignition process
When designing your application platform take into account that powering up MC55/56
requires the following steps.
· The ignition line cannot be operated until V
· The ignition line shall not be operated earlier than 10ms after the last falling edge of VDD.
· 10ms after V
has reached 3.0V the ignition line can be switched low. The duration of
BATT+
the falling edge must not exceed 1ms.
· Another 100ms are required to power up the module.
· Ensure that V
does not fall below 3.0V while the ignition line is driven. Otherwise the
BATT+
module cannot be activated.
· If the VDDLP line is fed from an external power supply as explained in Chapter 3.8, the
/IGT line is HiZ before the rising edge of BATT+.
3.0V
passes the level of 3.0V.
BATT+
BATT+
/IGT
BATT+
/IGT
0V
HiZ
10ms
min. 100ms
max. 1ms
Figure 4: Timing of power-on process if VDDLP is not used
3.0V
0V
HiZ
HiZ
HiZ
10ms
min. 100ms
max. 1ms
Figure 5: Timing of power-on process if VDDLP is fed from external source
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3.3.1.3 Turn on MC55/56 using the POWER signal
As detailed in Chapter 3.5.3, the charging adapter can be connected regardless of the
module’s operating mode (except for Alarm mode).
If the charger is connected to the charger input of the external charging circuit and the
module’s POWER pin while MC55/56 is off, processor controlled fast charging starts (see
Chapter 3.5.2). MC55/56 enters a restricted mode, referred to as Charge-only mode where
only the charging algorithm will be launched.
During the Charge-only mode MC55/56 is neither logged on to the GSM network nor are the
serial interfaces fully accessible. To switch to normal operation and log on to the GSM
network, the /IGT line needs to be activated.
3.3.1.4 Turn on MC55/56 using the RTC (Alarm mode)
Another power-on approach is to use the RTC, which is constantly supplied with power from
a separate voltage regulator in the power supply ASIC. The RTC provides an alert function,
which allows the MC55/56 to wake up whilst the internal voltage regulators are off. To
prevent the engine from unintentionally logging into the GSM network, this procedure only
enables restricted operation, referred to as Alarm mode. It must not be confused with a
wake-up or alarm call that can be activated by using the same AT command, but without
switching off power.
Use the AT+CALA command to set the alarm time. The RTC retains the alarm time if
MC55/56 was powered down by AT^SMSO. Once the alarm is timed out and executed,
MC55/56 enters into the Alarm mode. This is indicated by an Unsolicited Result Code (URC)
which reads:
^SYSSTART ALARM MODE
Note that this URC is the only indication of the Alarm mode and will not appear when
autobauding was activated (due to the missing synchronization between DTE and DCE upon
start-up). Therefore, it is recommended to select a fixed baudrate before using the Alarm
mode. In Alarm mode only a limited number of AT commands is available. For further
instructions refer to the AT Command Set.
Table 5: AT commands available in Alarm mode
AT command Use
AT+CALA Set alarm time
AT+CCLK Set date and time of RTC
AT^SBC In Alarm mode, you can only query the present current consumption and check
whether or not a charger is connected. The battery capacity is returned as 0,
regardless of the actual voltage (since the values measured directly on the cell are
not delivered to the module).
AT^SCTM Query temperature range, enable/disable URCs to report critical temperature ranges
AT^SMSO Power down GSM engine
For the GSM engine to change from the Alarm mode to full operation (normal operating
mode) it is necessary to drive the ignition line to ground. This must be implemented in your
host application as described in Chapter 3.3.1.1.
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