SIM Tech SimCom SIM340, Проектирование аппаратного обеспечения

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SIM340 Hardware Design
Debug port Serial Port can be used for CSD FAX, GPRS service and send AT
command of controlling module.
Serial Port can use multiplexing function.
Autobauding supports baud rate from 4800 bps to 115200bps.
Debug Port: Two lines on Serial Port Interface /TXD and /RXD
Debug Port only used for debugging
Phonebook management Support phonebook types: SM, FD, LD, RC, ON, MC.
SIM Application Toolkit Support SAT class 3, GSM 11.14 Release 99
Real time clock Implemented
Timer function Programmable via AT command
Physical characteristics Size: 40±0.15 x 33±0.15 x 3.3±0.3mm (including application
connector)
40±0.15 x 33±0.15 x 2.9±0.3mm (excluding application
connector)
Weight: 8g
Firmware upgrade Firmware upgrade by serial port.
The SIM340 does works, but deviations from the GSM specification may occur, For example,
both the frequency error and the phase error will be large.
Table
4
: Coding schemes and maximum net data rates over air interface
Coding scheme 1 Timeslot 2 Timeslot 4 Timeslot
CS-1: 9.05kbps 18.1kbps 36.2kbps
CS-2: 13.4kbps 26.8kbps 53.6kbps
CS-3: 15.6kbps 31.2kbps 62.4kbps
CS-4: 21.4kbps 42.8kbps 85.6kbps
2.2 SIM340 functional diagram
The following figure shows a functional diagram of the SIM340 and illustrates the mainly
functional part:
The GSM baseband engine
Flash and SRAM
The GSM radio frequency part
The antenna interface
The board-to-board interface
SIM340_HD_V3.09 18.03.2009
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