I am currently working with Xbee series 2 Zigbee modules for my application. For the initial test and setup of the application, I tried to do a point to point between two of these modules. I configured one Xbee as Router AT, set the PAN ID, set destination ID as 0x0 (to communicate to the coordinator). I then connected this router to a mbed microcontroller over UART and wrote a simple program to transmit characters. I then took the other Xbee, connected to X-CTU and setup as Coordinator AT with same PAN ID. Following this I switch X-CTU to console window (to monitor messages from router) and then switch on my microcontroller+Xbee router. This arrangement works perfectly with me receving messages in console.
Following this, I look to switch off my router, and update function set of coordinator to Coordinator API. I make no changes to router config and let it remain in AT mode. After updating to API, I follow the same process, i.e., switch to console window on X-CTU and power on the router. However, in this case, I seem to be getting no data transmissions from the router at all.
Having observed this, I decided to revert back my coordinator to the AT mode. However, surprisingly now, even with the coordinator switched back to AT mode, I see no messages from the router at all. I was very confused because of this, and decided to do re update the firmware on the router to change to router AT(no real reason, just trying to get back to some working mode). Things started working now, which makes no sense at all. I am certain about the functioning of the UART interface on microcontroller, and so I assume this is something to do with the Xbee config.
What is the issue that I am missing here? Is it even possible to have router in AT mode and coordinator in API mode?(I assume it should be)
I am really stuck here people. Really appreciate any inputs.
P.S. One more piece of info, I ensure whenever I update the function set, I uncheck the "Force the module to maintain its current configuration" checkbox. Not sure if this info is useful.