Multitech SocketModem GSM, MTSMC-G1 Hardware Manual

SocketModem® GSM

MTSMC-G1

Hardware Guide for Developers

Copyright and Technical Support

Hardware Guide for Developers

SocketModem® GSM – MTSMC-G1

Copyright

This publication may not be reproduced, in whole or in part, without prior expressed written permission from Multi­Tech Systems, Inc. All rights reserved.

Copyright © 2008 by Multi-Tech Systems, Inc.
Multi-Tech Systems, Inc. makes no representations or warranties with respect to the contents hereof and specifically

disclaim any implied warranties of merchantability or fitness for any particular purpos e. F urthermore, Multi-Tech
Systems, Inc. reserves the right to revise this publication and to make changes from time to time in the content hereof
without obligation of Multi-Tech Systems, Inc. to notify any person or organization of such revisions or changes. See
the Multi-Tech Web site for current revisions of documentation.

Trademarks

Trademarks and Registered Trademarks of Multi-Tech Systems, Inc. are SocketModem and the Multi-Tech logo.

Record of Revisions
Revision Date Description

A 03/14/08 Initial release.
B 08/21/08 Updated the FCC statement on page 13.

World Headquarters

Multi-Tech Systems, Inc.
2205 Woodale Drive
Mounds View, Minnesota 55112
Phone: [phone] or 800-328-9717
Fax: [phone]
Internet Address: http://www.multitech.com

Technical Support
Country By Email By Phone

Europe, Middle East, Africa: [e-mail]

+(44) 118 959 7774

U.S., Canada, all others: [e-mail] 800-972-2439 or 763-717-5863

Multi-Tech Systems, Inc. SocketModem GSM Hardware Guide for Developers 2

Table of Contents

Table of Contents

Chapter 1 – SocketModem GSM................................................................................................................4

Introduction........................................................................................................................................... 4

Product Features..................................................................................................................................4

Product Ordering Information............................................................................................................. 4

Technical Specifications......................................................................................................................5

Mechanical Dimensions.......................................................................................................................6

SocketModem Configuration...............................................................................................................7

Serial Configuration..........................................................................................................................7

Electrical Characteristics and Power Consumption......................................................................... 9

Electrical Characteristics..................................................................................................................9

Power Consumption......................................................................................................................... 9

LED Indicators ....................................................................................................................................10

RF Interface......................................................................................................................................... 10

Upgrading Firmware........................................................................................................................... 11

Chapter 2 – The Antenna System............................................................................................................12

Antenna System for Embedded GSM Modems...............................................................................12

RF Specifications................................................................................................................................12

Chapter 3 – Design Considerations........................................................................................................14

Noise Suppression Design Considerations.....................................................................................14

PC Board Layout Guidelines............................................................................................................. 14

Electromagnetic Interference (EMI) Considerations....................................................................... 15

Electrostatic Discharge Control........................................................................................................ 15

Chapter 4 – Safety and Regulatory Compliance....................................................................................16

Safety Notices and Warnings............................................................................................................16

Telecom Safety Warning................................................................................................................16

Wireless Safety..............................................................................................................................16

Certifications, Approvals, Compliance, and Requirements...........................................................18

Wireless Approvals ........................................................................................................................18

Regulatory Compliance Statements ..............................................................................................19

Waste Electrical and Electronic Equipment Statement..................................................................20

Restriction of the Use of Hazardous Substances (RoHS).............................................................21

Information on HS/TS Substances According to Chinese Standards............................................ 22

Information on HS/TS Substances According to Chinese Standards (in Chinese).......................23

Chapter 5 – The SocketModem Developer Board.................................................................................. 24

SocketModem Developer Board Block Diagram ...........................................................................24

The Developer Board Components ..................................................................................................25

Board Components........................................................................................................................26

Pins and Corresponding Signals....................................................................................................26

Table of Switch Blocks...................................................................................................................27

Developer Board Schematics ........................................................................................................28

Chapter 6 – Multi-Tech Warranty Statement ..........................................................................................32

The Multi-Tech Systems, Inc. Warranty Policy................................................................................32

Index...........................................................................................................................................................34

Multi-Tech Systems, Inc. SocketModem GSM Hardware Guide for Developers 3

Chapter 1 – SocketModem GSM

Chapter 1 – SocketModem GSM

Introduction

The SocketModem® GSM wireless modem is a complete, ready-to-integrate communications device that
offers standards-based multi-band GSM/GPRS Class 10 performance. It is based on industry-standard
open interfaces and utilizes Multi-Tech’s universal socket design. This SocketModem includes an
embedded TCP/IP protocol stack to bring embedded Internet connectivity to any device.

Product Features

• Embedded TCP/IP stack with UDP and PING support

• Short Message Services (SMS) Features:

• Text and PDU, Point-to-Point, Cell broadcast

• AT command compatible

• Advanced management features include phone book management, fixed dialing number, real

time clock, and alarm management

• Large Memory SIM support to store/recall more than 127 text messages (SMS)

• Large Memory SIM support to store/recall more than 127 entries per phonebook

• Symstream multi-dimensional symbolic communication protocol

• Link Status (LS) LED and Signal Strength Indicator (SSI) LED on-board

Product Ordering Information

Product Description Region

MTSMC-G1 Quad-band GSM/GPRS SocketModem (850/1900 MHz Default) Global
MTSMC-G1-ED Quad-band GSM/GPRS SocketModem (900/1800 MHz Default) Global
MTSMC-G1-SS Quad-band GSM/GPRS SocketModem - Symstream Enabled

(850/1900 MHz Default)

MTSMC-G1-ED-SS Quad-band GSM/GPRS SocketModem - Symstream Enabled

(900/1800 MHz Default)

MTSMC-G1-XP-SS Quad-band GSM/GPRS SocketModem - Symstream Enabled -

External Power (850/1900 MHz Default)

MTSMC-G1-XP-ED-SS Quad-band GSM/GPRS SocketModem - Symstream Enabled -

External Power (900/1800 MHz Default)

How to Read the Table Above

Build Description

-G1 GSM/GPRS

-ED Euro Default, 900/1800 MHz

-SS Symstream Enabled

-XP External Power Source

Global

Global

Global

Global

Multi-Tech Systems, Inc. SocketModem GSM Hardware Guide for Developers 4

Technical Specifications

The SocketModem GSM meets the following specifications:

Category

Standards
Bandwidth
Serial/Data Speed

Data Format
Data Error Correction
Data Compression
Fax Compatibility
Fax Class
Dimensions

Weight
Operating

Temperature
Storage Temperature
Humidity
Operating Voltage
Power Requirements

Connectors

IP Protocols
Supported

Approvals

Warranty

Description

GPRS Class 10
Quad-band 850/1900 or 900/1800 MHz GSM/GPRS
Serial interface supports DTE speeds to 921600 baud

Packet data up to 85.6K bps
Circuit-switched data (GPRS) up to 14.4K bps transparent and non-transparent

Asynchronous, transparent and non-transparent
MNP2
V.42bis
GSM
Class 1 and Class 2 Group 3

2.541” L × 1.045” W × 0.542” H (6.45cm x 2.65cm x 1.38cm) with SIM retracted

2.974” L × 1.045” W × 0.542” H (7.55cm x 2.65cm x 1.38cm) with SIM ejected
To be determined

-30° to +70° C (FCC certified operating temperature range is -30° to +50° C )

-40° to +85° C
20% to 90% (non-condensing)
5VDC

5V: Typical: To be determined (minimum 400mA)

Maximum Peak Current 2.0A
(Note: The VCC supply does not have to provide a constant high current

but must accommodate the short current spikes of about 1154µs every

4.651ms.)
Antenna: UFL button-type with maximum cable length of TBD” (TBD cm)
SIM: Standard 1.8V and 3V SIM receptacle
VCC/GND: Extra connector for retrofit situations in case VCC pin is not provided

with enough current (must be same 5V source as VCC pin) and cable length must
not cause more than TBD volts drop.

FTP client, ICMP, POP3 (receive mail), HTTP, SMTP (send mail), TCP/UDP
socket: To be determined at a later date.

Safety Certifications

UL 60950
cUL 60950
EN 60950
AS/NZS 60950:2000

EMC Approvals

FCC Part 22, 24
ETSI EN 301 489-7

Network

PTCRB

Two years

Chapter 1 – SocketModem GSM

Multi-Tech Systems, Inc. SocketModem GSM Hardware Guide for Developers 5

Mechanical Dimensions

Chapter 1 – SocketModem GSM

SocketModem GSM Mechanical Drawing

Multi-Tech Systems, Inc. SocketModem GSM Hardware Guide for Developers 6

SocketModem Configuration

Serial Configuration

Note: The bolded, shaded pins are the SocketModem GSM active pins.

Chapter 1 – SocketModem GSM

Multi-Tech Systems, Inc. SocketModem GSM Hardware Guide for Developers 7

Top View

SocketModem Pinout

Chapter 1 – SocketModem GSM

Pinout Descriptions

Pin Signal In/Out Description

-Reset I Device Reset (with pull-up). The active low -RESET input resets the device logic

24

and returns the configuration of the device to the original factory default values or
"stored values" in the NVRAM. -RESET is tied to VCC through a time-constant
circuit for "Power-on-Reset" functionality. The module is ready to accept commands
after about 6 seconds after power-on or reset.
This signal is used to force a reset procedure by providing low level during reset of
at least 500µs. The signal is considered an emergency reset only. A reset
procedure is already driven by internal hardware during the power-up sequence. If
no external reset is necessary, this input can be left open. If used (emergency
reset), it has to be driven by an open collector or an open drain.

GND I

26

-RTS I Request to Sent (Active Low). -RTS signal is used for hardware flow control. -RTS

33

-RXD O Received Data. The module uses the RXD line to send data to the DTE and to

34

-TXD I Transmitted Data. The DTE uses the -TXD line to send data to the module for

35

-RI O RING (Active Low). Incoming ring signal from phone.

36

-DSR O Data Set Ready (Active Low). -DSR indicates module status to the DTE. -DSR

37

-CTS O Clear to Send (Active Low). -CTS is controlled by the module to indicate whether

38

-DCD O Data Carrier Detect (Active Low). -DCD output is ON (low) when a data

39

-DTR I Data Terminal Ready (Active Low). The -DTR input is turned ON (low) when the

40

GND I

41

VCC I DC Input Power. 5V DC power.

61

GND I Analog Ground. Analog ground is tied common with DGND on the SocketModem.

63

Logic Ground.

input ON (low) indicates that the DTE is ready to send data to the modem. In the
command state, the modem ignores -RTS.
Note: When the -RTS pin is not in use, it should be tied low.

send module responses to the DTE. In command mode, -RXD data presents the
module responses to the DTE. Module responses take priority over incoming data
when the two signals are in competition for -RXD. When no data is transmitted, the
signal is held in mark condition.

transmission or to transmit commands to the module. The DTE holds this circuit in
mark state when no data is being transmitted or during intervals between
characters.

Ring Indicate. -RI output ON (low) indicates the presence of an ON segment of a
ring signal on the telephone line. The modem will not go off-hook when -RI is active;
the modem waits for -RI to go inactive before going off-hook.

OFF (high) indicates that the DTE is to disregard all signals appearing on the
interchange circuits except Ring Indicator (-RI). It reflects the status of the local data
set and does not indicate an actual link with any remote data equipment.

or not the module is ready to transmit data. -CTS ON indicates to the DTE that
signals on TXD will be transmitted. -CTS OFF indicates to the DTE that it should not
transfer data on TXD.

connection is established and the module is ready to send/receive data.

DTE is ready to communicate. -DTR ON prepares the modem to be connected, and,
once connected, maintains the connection. -DTR OFF places the modem in the
disconnect state under control of the &Dn and &Qn commands.

Note: When the -DTR pin is not in use, it should be tied low.
Logic Ground.

To minimize potential ground noise issues, connect audio circuit return to AGND.

Multi-Tech Systems, Inc. SocketModem GSM Hardware Guide for Developers 8

Chapter 1 – SocketModem GSM

Electrical Characteristics and Power
Consumption

Note: These are preliminary measurements.

Electrical Characteristics

5V DC Characteristics (VDD = 5V ± 0.25V)

Digital Inputs
–DTR (40), –TXD (35), –RTS (33)
–RESET Input High

Digital Outputs
–DCD (39), –CTS (38), –DSR (37), –RI (36), –RXD (34)

VDDMAX

= 5.25V

Input High
Min 2.0V

Min 2.0V
Output High
Min 4V

Input Low
Max 0.8V
Input Low
Max 0.5V
Output Low
Max 0.4V

Current
Drive: 2mA

Digital Input Capacitance 5 pF

Power Consumption

Power Consumption in EGSM900 and GSM850 @ 25 degrees C

Conditions I

+5V
+5V
+5V
+5V

During TX bursts @ 2W 1.2 A 1.3 A
Average @ 2W 250mA 320mA
Average @ 0.5W 180mA 200mA
Average idle mode 15mA 25mA

Power Consumption in GSM1800 & 1900 MHz @ 25 degrees C

Conditions I

+5V During TX bursts @1W 1.1 A 1.2 A
+5V Average @1W 210mA 235mA
+5V Average @ 0.25W 165mA 185mA
+5V Average idle mode 15mA 25mA

Power Consumption in EGSM/GPRS 900 MHz and GSM/GRPS 850 MHz Mode Class 10

Conditions I

+5V
+5V
+5V
+5V

During TX bursts @ 2W 1.2 A 1.3 A
Average @ 2W 420mA 470mA
Average @ 0.5W 280mA 320mA
Average idle mode 15mA 25mA

I

NOM

I

NOM

I

NOM

MAX

MAX

MAX

Power Consumption in GSM/GRPS 1800 MHz and GSM/GRPS 1900 MHz Class 10

Conditions I

+5V
+5V
+5V
+5V

Multi-Tech Systems, Inc. SocketModem GSM Hardware Guide for Developers 9

During TX bursts @ 1W 1.1 A peak 1.2 A peak
Average @ 1W 350mA 400mA
Average @ 0.25W 180mA 210mA
Average idle mode 15mA 25mA

I

NOM

MAX

Chapter 1 – SocketModem GSM

LED Indicators

The LEDs are used to indicate the working mode of the SocketModem. The LS LED indicates
Network Link Status and Network Strength

Network – defined by WMP100

Signal What Is Indicated

Off Processor Off
On Processor On – Not registered on the network
Slow Flash (on 200ms, off 2s) Registered on network
Quick flash (on 200ms, off 600ms) Registered on the network – Communication in

progress

Very quick flash (on 100ms, off 200ms) Bad software; software is bad or not compatible

Signal Strength

Signal What Is Indicated

Off Processor off or modem not registered on network
On Good GSM signal (RSSI >= 12)
Quick flash (on 200ms, off 600ms) Weak GSM signal (7 <= RSSI < 12)
Very quick flash (on 100ms, off 200ms) Very weak or no GSM signal (RSSI < 7)

RF Interface

Radio Characteristics

GSM 850 EGSM 900 GSM 1800 GSM 1900

Frequency RX 869 to 894 MHz 925 to 960 MHz 1805 to 1880 MHz 1930 to 1990 MHz
Frequency TX 824 to 849 MHz 880 to 915 MHz 1710 to 1785 MHz 1850 to 1910 MHz
RF Power
Stand

2W at 12.5% duty
cycle

2W at 12.5% duty
cycle

1W at 12.5% duty
cycle

1W at 12.5% duty

cycle
Impedance 50 ohms
VSWR <2
Typical Radiated Gain 0 dBi on azimuth plane

RF Performances

RF performances are compliant with the ETSI recommendation 05.05 and 11.10.
The main parameters are:

Receiver Features

• EGSM Sensitivity : < -104 dBm

• GSM 1800/GSM 1900 Sensitivity : < -102 dBm

• Selectivity @ 200 kHz : > +9 dBc

• Selectivity @ 400 kHz : > +41 dBc

• Dynamic range : 62 dB

• Intermodulation : > -43 dBm

• Co-channel rejection : + 9 dBc

Transmitter Features

• Maximum output power (EGSM) : 33 dBm ± 2 dB

• Maximum output power (DCS/PCS) : 30 dBm ± 2 dB

• Minimum output power (EGSM): 5 dBm ± 5 dB

• Minimum output power (DCS/PCS): 0 dBm ± 5 dB

• H2 level : < -30 dBm

• H3 level : < -30 dBm

• Noise in 925 - 935 MHz : < -67 dBm

• Noise in 935 - 960 MHz : < -79 dBm

• Noise in 1805 - 1880 MHz : < -71 dBm

• Phase error at peak power : < 5 ° RMS

• Frequency error : ± 0.1 ppm max

RF Connection

The RF connector on the SocketModem GSM is a UFL standard type. An antenna can be directly
connected through a mating UFL to SMA adapter.

Multi-Tech Systems, Inc. SocketModem GSM Hardware Guide for Developers 10

Upgrading Firmware

Upgrading the Firmware will be addressed in a later revision of thi s document.

Chapter 1 – SocketModem GSM

Multi-Tech Systems, Inc. SocketModem GSM Hardware Guide for Developers 11