Communicating with Mote over serial port


#1

Hi,
I’ve been hitting a weird problem controlling the mote directly via a serial port rather than via the python library and I’m wondering if I’m maybe missing something in how the protocol works.

I’ve got mote sticks attached to all 4 channels and send the following to set the pixels on the first channel.

  • Configure channel 1 with 16 pixels and no gamma correction
    m, o, t, e, c, 1, 16, 0
  • Set the pixels on channel 1 to red
    m, o, t, e, o, 0, 0, 255, 0, 0, 255 … and so on (0, 0, 255 for all 16 pixels)
  • I then close the port

Now this is the weird bit, if I open the port again and send the same sequence again the first stick illuminates as before (all red), but the first 2 pixels on the second channel also light up with what looks like white (0,0,0) and blue(0,0,255).

I’m at a bit of a loss as to why this is happening.

You can try this out by running the rgb.go example twice from https://github.com/johnmccabe/mote (I’m porting the python library to go).

Any suggestions?
/John


#2

hmm, it does it as well when you use the python library (edit the rgb.py example to only configure a single channel)


#3

This could be a firmware bug with Mote, or possibly even just noise coupling in from one channel to another. It’s not something I’ve observed though, but I’ve grabbed a Mote to try it out.


#4

Thanks, would be nice to see if its just me.

Just pushing up the last missing methods to the library at the moment.


#5

Not just you. I’m seeing exactly the same thing!

Edit: I only have one working Mote stick 'cos I accidentally grabbed one that I had for diagnosis. D’oh! But if I plug just a stick into the second port, I see the same white and blue pixels.


#6

Cool, thanks for checking :D