Modem seems to be asleep

I’m using API mode with the xbee pro 2.4. I send out a transmit request ( frame 0x10 ), but I need to send the request out twice to get a response. It’s like the first time I send it out, the modem seems to be asleep. On the second second, I get a response. If I keep sending out requests after that, I get back responses. Any idea what could be going on? Thanks.

Has your problem solved?I am having the same trouble.Didn’t get any results yet so far.

Are you really using DigiMesh 2.4, or ZigBee 2.4?

(I understand this is the DM 24. forum, but people often post on the wrong ones if they arrived here via a google search.)

If you’re using an XBee module that sleeps, you need to check it’s status pins (-CTS on pin 12 and -SLEEP on pin 13) to confirm that it’s awake before trying to send serial data to it.