More than 4 motors?

[cbradburne]

Correct me if I'm wrong, but I believe TS4 will only cover 4 synchronous motors, and that there was mention of re-writing the code to allow for more. I fully appreciate this is not a small task, but I wondered if this is something you were still looking in to?
As always, your time working on TeensyStep is very much appreciated.

[maxitech]

Hi! I encountered the same issue when trying to control more than 4 motors simultaneously. After some research and testing, I found a solution that worked for me: adding additional timer modules to the TimerFactory.
By adding more timer modules to the TimerFactory, you can extend the capacity.

How it works

The Teensy 4.x uses TMR timers, and each TMR module has 4 timer channels available. By default, the library registers one module (typically TMRModule<3>) in teensystep4.cpp, which provides enough timers for 4 motors. However, if you need to control more motors, you can add additional timer modules manually. For example:

TimerFactory::attachModule(new TMRModule<0>());

This allows up to 8 motors by combining TMRModule<0> and the default TMRModule<3>.

Note: I’ve successfully tested this setup with 6 motors, as I don’t currently have the hardware for more. Based on the architecture of the TMR modules, this approach should theoretically work with up to 8 motors when using 2 TMR modules. If anyone tests it with more motors, feel free to share your results!

Useful Resource for Timer Modules on Teensy Boards

For more detailed information about TMR modules, including how the Teensy 4.x uses these timers, check out this excellent resource:
luni64/TeensyTimerTool GitHub Wiki

I hope this helps you or others that come along!

...M