Yes I noticed the same thing with my robot. The speed at 100 or below is significantly lower than what is possible for my DC motors. I generally run with a value of 128, but I have heard from RoboticsConnection (RC) that the specified maximum is a value of 100, and that the command should really return an error when using a value of 128.
Perhaps RC can comment on why values higher than 100 are not supported, and why the motor speed is not maxed when using a value of 100 as intended.
James Y. Wilson http://www.learningce.com Fortudine Vincimus!
Hey Patrick, Jim,
The DifferentialMotorController class uses the same underlying 'pwm' command to control the DC motors as does the PWMDCMotorController class, it's just that it sends a command for both motors at the same time to the Serializer (so they start at the same time). Thus, the 'pwm' command in the Serializer firmware is supposed to only support speeds from 0 to 100. However, as you both have pointed out, you can obtain an increase in motor speed using values higher than 100.
This is not "as designed", and we'll look into this. Ringo might have an idea why this is the case.
Nontheless, the bug isn't in the Serializer .NET lib, but rather in the firmware. Of course, once we figure this out, I will still add some range checking to both the firmware and Serializer .NET lib in the next release. :)
We'll let you know later this afternoon what we find. :)
Thanks!
Yep, there's definitely a bug in the firmware for 'pwm'. Depending on the timing of the onboard interrupts, etc. the max value of pwm can change. At some point, we changed some timing parameters somewhere, and basically introduced this bug. We will fix it tonight, and post a new firmware release on the Serializer Page, and I'll post a link in a new topic in this forum.
If you can wait until tonight for the fix, I'm pretty sure you'll be able to go up to 127/128 for max pwm values, and get the results you desire for max motor speeds.
Good catch guys! :)
There is definitely a scaler missing. I'll figure it out tonight and get it fixed and can post a new FW version on the Website.
Ringo