Xigbee Problem Please Help

Hello,

   I am working on two zigbee RCM4510 module and wanting to use one as coordinator and one as end device without the use of any Dongle or OC intevention. How can i do that please help. I have downloaded the Coordinator F/W in one device and the End Device firmware in another device still it is not working i am not able to debug the situation. The end device givers error on running program :timer expires (error code -62) and at other time it shows network discovery done even if the coordinator is not active or powered on. 

    Please help

With Regards

Aravind Singh