Posted on 39 Comments

Stepstuck revisited… DRV8825

In April 2012 Nophead from HydraRaptor fame, brought us the micro-current hack for the pololu 4988 stepper motor driver carrier. http://hydraraptor.blogspot.com/2012/04/stepstuck.html

Now, it is my turn…

The amazing DRV8825 driver carrier has a similar flaw, strange jumping of steps in 32th micro-stepping mode.

After doing a bit of research, it seems that we need to put the chip in FAST decay mode, by pulling the DECAY line of the chip to 5V.  Luckily the DRV has exposed pins, so I carefully soldered the DECAY pin (19) to the M2 pin on the board (will be 5V when 32th uStepping is enabled.)

Decay mode modification - FAST mode
Decay mode modification – FAST mode

Movement as smooth as butter!

Posted on 39 Comments
Posted on Leave a comment

Irony

After giving up on getting any reprap related spares anywhere in South Africa, and after commissioning the making of the circuit-boards for my RAMPS and stepstick boards, I found a little computer store RIGHT ON MY DOORSTEP that stocks amongst other things, Pololu stepper drivers, Arduino, Sparkfun stuff, the elusive headers etc.

http://robotics.org.za/

They are situated in the shopping center behind the Centurion Macro, close to the Gym.

What Irony! At least I will save a few bucks in the looooong run by doing what I did 😉

Posted on Leave a comment