I configured xbee pro s2c-A as router and xbee-B as a coordinator but in API mode the only router can transfer packets to coordinator but coordinator transmit data packets to self what is the problem?
Check the 64 bit address you are using in your API TX request frame. From the Router to the Coordinator it can be either the SH and SL of the coordinator or the address 0. From the Coordinator out, it needs to be either the broadcast address of 0xFFFF or the destination nodes SL and SH values.
Are you using DigiMesh xbees modules, right? If you really are, DigiMesh doesn’t work with the idea of coordenator/router/enddevice, they’re all digimeshs, so they work at the same level.
take a look at this link:
https://www.digi.com/blog/networking/what-are-the-differences-between-digimesh-and-zigbee-mesh/
see if it helps.
cheers