This document contains assorted troubleshooting tips for resolving RCI over serial problems.
1) RCI over serial uses the following serial port settings (regardless of previous "data" mode connection settings):
9600 baud, 8 data bits, 1 stop bit, no parity, no flow control
2) You will know the modules serial port will be in "RCI" mode upon receiving the following string:
on the other hand, there is no string indicating that the module is back in "data" mode.
3) The RCI over Serial option is available only on serial port 1,
4) Verify that the serial port is not in a configuration which is dependent on DSR state changes (i.e. for autconnect, etc).
5) Don''''t use DSR/DTR hardware flow control.
6) In order to go into RCI mode DSR must be active. At the TTL level, the signals are active low approaching Ground, example: 0v). At the RS-232 level, the voltage for the active condition is a positive voltage referenced from the signal ground (example: 3.3v or greater).
7) The device is sensitive to DSR only when the serial port is idle.
Jun 13, 2019