ZigBee XB24CZ7WIT-004 s2c 802.15.4 firmware loaded 1 coordinator on the tx side 2 end devices on the leds. I am trying to control multiple leds with one transmitter from arduinos at the same time. I checked serial communications of the arduino by using wires. TX and rx works by wire and codes are correct. I connected xbees tx to rx and rx to tx 3.3v and gnd. I choosed AT mode and broadcast mode. (on coordinator pan id=2017 DL,DH=0, MY=FFFF ce=enabled on end devices I copied SL,SH of the coord. to DH,DL values of end devices pan id=2017. Is that correct? By the way Thank you very much mvut.