I have 2 XBees S1 Pro, one is transmitter in API mode, the other one is reciever in transparent mode. I am sending data packets via MCU PIC30F5011. If I try to send the packet from transmitter via uart the packet is not sent. However if i connect the xbee into a computer and try to send the same packet with XCTU or LabView the packet is fine and the Xbee have no problem sending it, so the packet must be correct. I also tried connecting the uart into computer and check the output in Teraterm and the packet looks exactly the same as the one from XCTU.