Dual MC33926 Motor Driver Shield | Motor slow in reverse

Hi there :wink:

we are using the Dual MC33926 Motor Driver Shield in conjunction with Arduino Uno and a 12V/~1A DC motor.

When using positive speed values everything works fine - with the same negative values we get a lot less power and speed.
Also it seems to us that it gets hot much faster when spinning with negative values.

We have the same problem with all other motors we tested.

We use the http://github.com/pololu/dual-mc33926-motor-shield library.
md.setM1Speed(400) works perfectly - md.setM1Speed(-400) not…

Thank you very much in advance and please let us know if you need any more info.

All the best,

Hello, Johannes.

What kind of mechanical load are you using with the motors? Do you have a datasheet or any more details about your motors? Do you have any pictures of your setup including any connections you are making to the motor driver shield you could post here? Are you using both channels of the shield and do they both exhibit the same behavior? Have you tried anything like swapping the leads of the motor on the shield and inverting the direction logic in your code to see if the problem switches to only positive values?