I change my laser all the time to test various motor driver and controller setups. I recently had an strange issue with the DSP. On some speed and stepover values, I was getting angled or skewed engravings. Here is a picture on the problem. The square was done in cut mode then the same square was done in engrave mode.
- angle.JPG (23.83 KiB) Viewed 19847 times
The problem turned out to be the way I attached the steppers. The DSP has + and - terminals for the step and drive signals. I tried a few drivers in including opto isolated types and was able to repeat and solve the problem by wiring.
My guess is it has to do with timing of the direction and step signals. If you don't have the right connection, at one end of the raster it is either losing a step or stepping before the direction changes. Whatever it is it slowly walks in one direction an extra step or two per raster.
If you see the problem try changing your wiring scheme.