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WiFire 200Mhz AccelStepper max stepper speed test

Created Tue, 25 Aug 2015 14:44:13 +0000 by EmbeddedMan


EmbeddedMan

Tue, 25 Aug 2015 14:44:13 +0000

In answering a great question on the AccelStepper e-mail list, I did a quick test of the WiFire board and how many AccelStepper objects it could handle at what speed.

My results are as follows : we can do 10 AccelStepper stepper motor objects at up to 10Ksteps/second, or 20 objects at up to 4Ksteps/second before we load the CPU down enough to cause the steppers to not turn at the expected speed. This is with the just released MPIDE version and the latest AccelStepper library. I verified my results by looking at the STEP outputs of each stepper with a logic analyzer and measuring the time between step pulses.

Note that the WiFire board has just barely enough I/O pins for 20 stepper motors (STEP and DIRECTION for each motor driver) - you have to use all of the analog I/O as stepper control, but it does work.

I did not try to run less than 10 stepper motors at the same time - I'm certain that you could get north of 20K or 30K steps/second if you cut down the number of stepper motors.

Anyway, for anybody looking to run a lot of simultaneous AccelStepper stepper motors from an Arduino compatible board, I'm pretty sure you can't beat WiFire at this point in time.

*Brian