Short Description

The IMODGSM-E3 is the first Bausch GSM/GPRS embedded I-module (56,4 x 56,4 mm), ment for all kinds of remote M2M alarm monitoring and utility applications.
Supporting FOTA (Firmware over the Air) as an option - the firmware is loaded onto the flash module - the IMODGSM-E3 integrates a quad band Enfora Enabler-IIIG-0308-11 cellular module, an AVR processor (with program and debug functionality) and a 3V3 serial TTL Interface.The module is FCC (Parts 15, 22 & 24), CE, IC and RoHS compliant and has GCF v3.27.0, PTCRB v3.12.0, AT&T, Rogers and other worldwide operator certifications.



Product Details

Product Code: IMODGSM-E3
Product Name: IMODGSM-E3

Technical Overview

Bausch Datacom is specialized in the design and development of telecom modules for embedded PSTN, ISDN and wireless (GSM, 2G, 3G...) applications. The company has a long experience (since 1990) designing modems and line interfaces for set top Boxes, cash registers, alarm systems, P.O.S, metering systems and many other applications. These modem designs are used world wide with approvals in many countries. The company can offer services from the very first idea, schematics, PCB designs, approval, compliance testing and even coordination of external production if necessary.

The latest designed embedded module is the IMODGSM-E3, a wireless GSM/GPRS (2G) I-Module - 56,4 x 56,4 mm - supporting all kind of remote M2M alarm monitoring and utility applications.

Next to this new IMODGSM-E3 the Silicon Labs based SMD24xx for example is a complete and proven product range of PSTN modem modules that meet global telephone line requirements. Available in a socket (64,5mm x 26,5mm) size footprint, the device is ideal for embedded modem applications due to its small board space, low power consumption and global compliance. The device is available in 5 different versions, ranging from V.92 down to V.22bis. The module allows you to reduce time to market by using a ready to use approved solution.
For a complete overview of I-modules, socket modules and V.24 RS-232 PSTN modem modules, please visit: and

The recently designed Conexant Harley 2 based SM_H2_3V3 Socketmodem is a V.92 (56K), 3.3V socketmodem (64,5 x 26,5 mm) with voice listen-in option (full duplex speakerphone). This module is ideal for embedded medical, metering and alarm applications since it offers very low operating power requirements, a small board space, a worldwide compliance and a 3 kV dielectric withstanding voltage. Specifically for alarm applications it supports the SIA alarm protocol and Contact ID.
(Please visit: .

Product Specifications

Dimensions and pin layout 

Length   56.4 ± 0.2 mm
Width     56.4 ± 0.2 mm
Mounting holes  D 2.8 mm

DTE Interface: TTL 3V3 Connector  - 24 pin connector

Power supply and interfaces

SIM interface:
•1.8/3-Volt SIM capability

Power supply:
•Voltage: 3V3 ±5%
•Maximum current: 600 mA Average ( GPRS full power), 2A peak
•Recommend: 2000 uF capacitor on VCC

Antenna interface:
•SMA female connector


LED D1  Blinks fast on start-up , wait for boot-loader enter command
              Blinks every 1 second in normal operation
LED D3  EIII Ring Indicator
LED D4  GSM power ON

Radio Performance

Embedded GSM/GPRS (2G) Enfora Enabler-IIIG-0308-11 cellular module
Radio frequency: 850/900/1800/1900 MHz
Sensitivity: -106 dB ( Typical)
Transmit Power: Class 4 ( 2W @ 850/900 MHz)
                          Class 1 ( 1W @ 1800/1900 MHz)

Modem operation

The modem module is build around an Enfora Enabler III GSM module and an Atmel AVR RISC processor.
All serial communication is passed transparent to the E3 module.
The AVR application listens to this communication from the host and acts on special command.
It also controls the power up sequences for the Enabler 3 module.
For the complete Enfora AT commands description guide, see under "Manuals" below.The AVR has also a boot loader on board which allows an application to be programmed via uart.

Firmware versions

Enabler 3: PKG51
AVR Application: V6.00
AVR Boot: V1

Serial interface format

Asynchronious 9600 bps, 8bits, No parity, 1 stopbit 

Application description

AVR application version V6.00
The AVR listens to the serial communication at 9600,8bits,N,1 and can act on some special commands.
These commands need to be preceded by a non-activity of approximately 1 second. This is to avoid unwanted activation in data mode. There is no command line editing possible on these commands.

Command format: <pause>AT&Gn<cr>
n=0 Reset E3 module
n=1 Recycle power on EIII module
n=2 Reset complete module, can be used to enter boot loader.
n=3 Read application firmware version
n=4 Read GSM power supply voltage

The GSM power up message (‘ AT-Command Interpreter ready’) will only be seen when the module was
configured with +IPR=9600&W. If the AT&F&W command is given, the module will be configured for
+IPR=0 and the message will not be send at 9600 baud. The host will probably receive nothing or some
garbage characters and should ignore this.

For more information: see the "Enfora Enabler 3 AT Command manual" and "Modem Manual"below.

Boot loader

The AVR bootloader section is programmed with a modified XBOOT AVR boot loader to allow the programming of a new application via the serial port.
Upon power up or reset, the bootloader will wait for approximately 5 seconds for the XBOOT sync character (0x1B).
The AVRDUDE program can be used to program a new application.
The sequence to program a new application is:
•give AT&G2 command.
•start avrdude within 5 seconds.
Example AVRDUDE command for programming imodgsm.hex via com5 from windows command line:
avrdude -p x128a1 -P com5 -c avr109 -b 9600 -U flash:w:imodgsm.hex


The module has a PDI header (JP2) connected directly to the program and debug interface of the AVR controller. This allows programming and debugging of AVR applications.

FOTA (firmware over the air)

See manual below or call us for more information.

Environmental parameters

Operating temperature: -20 °C to +60 °C
Storage: -40 °C to +85 °C
Humidity: up to 95% non-condensing

Operating temperature of Enfora Enabler-IIIG-0308-11 cellular module: –30ºC to +85ºC

(Operator) certifications

Certifications: FCC Parts 15, 22 & 24; CE Mark; IC; RoHS compliant.
Operator certifications: GCF v3.27.0; PTCRB v3.12.0; AT&T; Rogers plus other worldwide certifications.

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