Follow up to this (see link) topic regarding motor speed control issues. I ran into the same issue with the Auto pHat motor controller where low speeds (below 230 setting) wont drive all motors. I think the issue is either that the Hbridge is in phase/enable mode, or it’s the PWM signal frequency.
Can the SCMD setting be changed via the SCMD control registers? For examaple I see SCMD_UPDATE_RATE. Does that change the PWM frequency?
Is there a way to change the DRV8835 HBridge mode from what I assume is phase/enable mode to IN/IN mode? I’m using python by the way.
Some TLDR details:
I noticed that this controller is essentially braking or applying power to the motor at all times unles I call disable(). For example when setting speed to 0, the driver is 50% positive direciton, 50% negative direction. Or for example setting the speed to 225, you would expect a 90% +positive duty cycle to the motor + terminal and 10% off. In reality it’s 90% positive, and 10% negative.
This is a pictures of the motor control M+ and M- signals with no motor attached.
Speed set to ~225
Thanks!
