Sim900D Functional Diagram - SIM Tech SIM900D HD Manual

SIM900D Hardware Design
Phonebook management
SIM Application Toolkit
Real time clock
Timer function
Physical characteristics
Firmware upgrade
Note: The SIM900D does work, but deviations from the GSM specification may occur.
Table4: Coding schemes and maximum net data rates over air interface
Coding scheme
CS-1:
CS-2:
CS-3:
CS-4:

2.2 SIM900D Functional Diagram

The following figure shows a functional diagram of the SIM900D and illustrates the mainly functional part:
The GSM baseband engine
Flash and SRAM
The GSM radio frequency part
The antenna interface
The Other interfaces
SIM900D_HD_V1.02
Debug port:
2-wire null modem interface DBG_TXD and DBG_RXD.
Can be used for debugging and upgrading firmware.
Support phonebook types: SM, FD, LD, RC, ON, MC.
Support SAT class 3, GSM 11.14 Release 99
Implemented
Programmable via AT command
Size: 33x 33 x 3 mm
Weight: 6.2g
Firmware upgrade by debug port.
1 Timeslot 2 Timeslot
9.05kbps 18.1kbps
13.4kbps 26.8kbps
15.6kbps 31.2kbps
21.4kbps 42.8kbps
4 Timeslot
36.2kbps
53.6kbps
62.4kbps
85.6kbps
15
09.04.2010