Passing DIO lines and serial
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Passing DIO lines and serial

by thefatmoop on Tue Jan 29, 2013 7:12 pm

When doing the digital line passing I noticed that there was a bunch of garbage going across the xbee's serial. I assumed those were the xbees talking about the DIO line. Is this correct?

we're controlling some large robotics with an xbee and need a wireless kill switch that bypasses any microcontrollers, and i'd like to keep it to 1 xbee instead of having to add a second just for the kill switch.
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Re: Passing DIO lines and serial

by adafruit_support_bill on Wed Jan 30, 2013 6:05 am

When doing the digital line passing I noticed that there was a bunch of garbage going across the xbee's serial. I assumed those were the xbees talking about the DIO line. Is this correct?

Yes. That is the line-passing protocol you are seeing.
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Re: Passing DIO lines and serial

by thefatmoop on Wed Jan 30, 2013 3:20 pm

Thanks a ton adafruit!
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Re: Passing DIO lines and serial

by thefatmoop on Tue Feb 05, 2013 2:41 am

For the wireless programming arduino with xbee guide on the adafruit site - there's a DIO line being used to reset the arduino. Do you think that this reset is the reason why wirelessly programming with the xbee is so unreliable? It's occasionally sending junk down the serial while the arduino is programming.

I remember someone at adagfruit said that it's probably because the xbees can't send and recieve data simultaneously with 0 latency.
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Re: Passing DIO lines and serial

by adafruit_support_bill on Tue Feb 05, 2013 6:52 am

I believe that the pin-passing protocol is strictly between XBees and does not get passed through to the Rx/Tx pins. I may have misunderstood your original post. I thought you were referring to communication activity on the modules, not actual signals out the serial port.

It is probably worth posting this question over at the Digi forums. They should be able to give you a more definitive answer.
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Re: Passing DIO lines and serial

by thefatmoop on Tue Feb 05, 2013 4:27 pm

When I stuck a logic analyzer on the serial I did see chatter when it was only passing DIO. I did change timeout settings on the modems though. Anyway here's a video showing how I got the wireless programming working VERY well, but it is buggy at 10+ feet.

anyway a video demo here showing the setup if anyone's interested
http://youtu.be/eHcDzwCFV5E

I'm not going to look into it too much - just need to get this project done.
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