RIM 1902G Integrator Manual page 56

Chapter 6: Interface specification
Pin Label
20 TX Transmitted data
This is an input to the radio modem. Its idle (no serial transmit activity) state is high.
This line is an asynchronous serial input to the radio modem, and should be connected to the
host terminal's transmit data output. This line carries data at a maximum of 115 200 bps.
Parameters are 8 bits, No parity, 1 stop bit. This baud rate can be changed using the
AT+IPR=<rate> AT command.
21 RX Received data
This line is an output from the radio modem. Its idle (no serial receive activity) state is high.
This line is an asynchronous serial output from the radio modem, and should be connected to
the host terminal's receive data input. This line carries data at at a maximum of 115 200 bps.
Parameters are 8 bits, No parity, 1 stop bit. The baud rate can be changed using the
AT+IPR=<rate> AT command.
22 RX2 Secondary Receive
This line is an output from the radio modem (for RIM internal use only).
Warning: All unused inputs to the radio should be tied to ground, and any unused outputs from the radio
should be left disconnected.
56
Description
RIM OEM Radio Modem for GSM/GPRS Wireless Networks