| Pin
| Description
| Comments |
|---|
| 1 | Audio Out | |
| 2 | Audio In | |
| 3 | Accessory Sense. GND to enable External Mic and Speaker (Analog) | |
| 4 | Audio Signal GND | |
| 5 | Portable handsfree In. | Internal/external mic and ear (0=External - open=Internal) |
| 6 | Music Mute Out, High when phone is used. | |
| 7 | In Flash Memory Voltage and Service Voltage,
In 0V=normal,+5V=test, +12V=test+flash | Test. Switch phone off and provide +5V and switch back on. (set comms at 9600, n,8,1) |
| 8 | Logic Out, Status On. Sources over 100mA. | +3.3V output |
| 9 | TX (Data Out) from Mobile Station. Debug messages appear here at 112KBaud when in debug mode. | TTL |
| 10 | Digital Ground and DC return | |
| 11 | Rx (Data in) | TTL |
| 12 | DC in for battery charging, DC out for accessory power | + external power supply 7.2Volt - 600mA |
