AccelStepper on Teensy++ 2.0 with 3 Pololu A4988 Drivers

[hopetech]

Howdy y'all,

I looked around on the forum but couldn't find any additional info on the hardware setup that appears on this page:

http://www.pjrc.com/teensy/td_libs_AccelStepper.html

Doesn't seem to be listed as a tutorial either. I'm interested in building something akin. Instructions / tutorial / BOM would be super. Links or such? Thanks.

More generally, my project requires driving 3 motors where the speed of each affects the others. If you increase one, the other two decrease. Or if you increase two, the other one slows... etc and so on. Any advice greatly appreciated.

 

[Wozzy]

Hopetech,

Here are links showing a similar stepper motor controller wired to a teensy 3.x along with some discussion on voltage settings:
https://plus.google.com/+RobertWozniak/posts/i2k3vbeMAvR
https://forum.pjrc.com/threads/23947-AccelStepper-Library-with-multiple-stepper-motors?p=33444&viewfull=1#post33444

Here's a link to the Panucatt Suresteppr SD8825 used in the above examples. (Note that the motor connections are reversed relative to the Pololu driver):
http://www.panucatt.com/product_p/sd8825.htm
And the documentation is here: http://files.panucatt.com/datasheets/sd8825_user_guide.pdf
The Panucatt driver has a slightly higher current capacity and 1/32 micro-step capability.

Here's a link with wiring information on the Pololu A4988 Stepper Motor Driver Board:
https://www.pololu.com/product/1182
I see that Pololu now also has an SD8825 driver board.

Here's a direct link to Mike McCauley's excellent accelstepper library:
http://www.airspayce.com/mikem/arduino/AccelStepper/index.html

WARNING! Double check your wiring!
Do not let the Motor Voltage touch the Teensy or it will instantly vaporize it!
(Lesson learned at 2:00 am one night)

The resistors are to limit the current on the micro-step programing pins, they can be anything from 0 to 1K... 470 ohms is a good value.
The decoupling capacitor is used reduce noise on the motor power supply. A 47µF to 1000µF electrolytic capacitor is acceptable.
Motor Power is from 12 to 35V.

Note: This info was originally from a PM, but I posted it here for the benefit of others.