I am using two XBEE S1 devices and want to communicate using an mbed microcontroller. I set both PAN IDs to 3332 using the XCTU app. For first XBEE: MY=1, DH=0, DL = 2 and second XBEE: MY=2, DH=0, DL=1 – all else is default. My simple initial test is to use a single mbed to send/receive bytes to/from the first XBEE and use the second XBEE + XCTU to receive and transmit bytes.
The mbed rx/tx port is set to 9600baud, 1 stop bit, no parity, no flow control. I also use a terminal program to see the bytes transmitted & received via the mbed.
I am using a XBEE breakout/USB device that is here:
http://www.epictinker.com/FT232RL-Tiny-Breakout-FOCA-v2-1-p/focav21.htm
When I use the two XBEEs with the breakout boards and both connected to the PC, The byte communication works as expected. I can communicate both ways.
The mbed and its XBEE are set up using a protoboard and the second XBEE is connected to the PC via its USB/breakout device – for this initial attempt.
What I see is that I can receive bytes at the mbed sent via the XCTU with its XBEE. However, I cannot seem to send bytes from the mbed to the second XBEE. Oddly, it seems that the mbed bytes are sent to its XBEE but immediately they are received back at the mbed from where they were transmitted. Its working like a tx-to-rx loopback.
The mbed serial rx/tx lines are connected to breakout board: rx-to-rx and tx-to-tx.