Dagu ComMotion Confusion

I purchased a Dagu Scamper to enter the OddBot art contest. Mechanical assemply completed without problems. Trying to get started with the software. Found the ComMotion instruction manual and a package called "ComMotion_Redboard_Demo" which contains four .ino files which compile and load into a Sparkfun redboard.

  • ComMotion_Commands.ino
  • ComMotion_Redboard_Demo.ino
  • IRdecode.ino
  • StatusUpdate.ino

This is where I am stalled. The demo code appears to expect the firmware on the ComMotion board to continuously transmit I2C messages approx twice per second. I see no I2C trafic after the initialization completes. Next step for me is to wire a scope/analyzer on the I2C lines.


  • Should I continue down this path?
  • Does anyone have a ComMotion code to share?
  • Do I need to load code into the 2 ComMotion controllers?

Update 8/1/2015

Got it moving in a sort of a straight line. Could not have been simpler. Just followed the user's guide. Trashed the original loop() function in the redbot demo and added function call to activate motion (used a function supplied in the demo package). OddBot suggested use of a compass and he obviously was speaking from experience.

One quirk I found with mine…

I got a commotion board a few weeks back and used that red board example as a starting point for my current project. One thing I noticed (after much head scratching) was the default i2c channel was actually 1 for the shield. I had to flip some dips to get rid of the conflict as my uno clone was also addressed 1. I googled an i2c scanner sketch which helped me identify the problem.

ComMotion Usage
Thanks for the status. I currently have only the shield but plan on adding an I2C compass soon.

Can’t get out of demo mode, please help

I’m using an Uno so I noticed I needed to insulate the shield from shorting on the usb housing.  I can scan the I2C bus and find the MCUs on 30/31 which I understand to be default.  I set the configuration, or have tried many, with demo bit set to 0.  The thing doesn’t seem to want to come out of demo mode, it plays it’s little song on reset and M3/M4 speed up and down no matter what I do.  The endTransmission function also returns 0 when I see them on the bus.  I have Vin jumper disconnected and a 12V 10A power supply connected.  I’m finding Dagu’s stock samples but I can’t see the “ComMotion_Redboard_Demo” stuff anywhere on the net.  I ultimately need to run a 4 wheel omni config and currently don’t have encoders so I also tried that mode as 18 (for 2 + 16 no encoders) and 19 (for 3 individual and no encoders).  Won’t seem to config through I2C.

Ideas for I2C would be much appreciated, or does anyone know if the default will actually support serial commands?