Copyright © Matrix Multimedia Ltd.
4
Board Layout
1.
Downstream 9-way D type connector.
2.
Patch System
3.
Logic level voltage shifter IC
4.
Screw terminals
5.
Switch mode inductor
6.
3V8 Switch mode regulator
7.
Headphones socket
8.
Microphone socket
9.
2V8 GSM Supply Reference
10.
GSM/GPRS network status LED
11.
SIM socket
12.
GSM/GPRS module
13.
GSM/GPRS module firmware upgrade port
14.
PCB antenna
1
2
3
2
2
6
5
4
7
8
9
10
11
12
13
14
Signal Connections using the Patch System
Signal
A (16F88)
B (16F877A)
Patch
Transmit Data (TXD)
Bit 5
Bit 6
Patch
Receive Data (RXD)
Bit 2
Bit 7
Patch
Request to send (RTS)
Bit 6
Bit 2
Patch
Clear to send (CTS)
Bit 7
Bit 5
Patch
Signal
1
Patch
Reset
Bit 1
Patch
Ring
Bit 3
Patch
