Channel DIO5 Dropping out


I have set my xbee to broadcast high/low signals over channels AD0-AD5. All of them work as expected, except for AD5. When the transmitter is broadcasting a high signal, after exactly 25 seconds the signal drops to low. All transmission channels are set to ATDn3, all receiver channels are set to ATDn4, where n=0 to 5.

I’m not sure if the problem is with the transmitter or receiver. Any ideas on why this would be or ideas for troubleshooting this problem?

Thanks in advance!

Your words are very confusing. Broadcast? How does one broadcast digital levels?

ATDn3 makes the pin an input/receiver, not output/transmitter.

ATDn4 makes the pin an output/transmitter, grounding the pin to 0v, not input/receiver.

What kind of hardware do you have? Internal or external pull-ups? Note that the XBee it self cannot raise a pin to ‘high’ without an internal or external pull-up.


Thanks for the response. I should have been more clear, but let me explain. We have 6 different transmitters connected to 1 receiver. Each transmitter takes in a digital signal from another sensor, and then the receiver then turns on LEDs depending if the channel is high or low.

All transmitters except for #5 (channel 5) work (light up the receiver LEDs when they should), and all have identical hardware. So I am thinking it must be due to the fact that channel 5 also serves as the “Associated indicator”, even though I believe I have disabled this function. I have hacked the hardware to use channel 6 instead of 5 and this works, but I would like to apply a software fix as this will save a considerable amount of time.

That makes more sense - but this is a bug if the XBee is intefering with DIO5 which <> 1.

What firmware are you running? Are your modules PRO or normal? To confirm, you have S1/802.15.4, right, not ZigBee.

Yes that is correct, it is an Xbee device, running on 802.15.4. We are running the latest firmware.

This does seem like a bug, I’ve gone over the settings many times and there is nothing that I can tell would cause this to happen.

An ‘expert’ mentioned to me that you should look at settings T0 to T7.

When Line Passing is enabled on any pins, by default any ‘non-default’ output will return to ‘default’ after 25.5 seconds. So you need to keep ‘refreshing’ the non-default output ot set T5 to 0.

Oh great. Thanks for the help!