Code for AS5600

[sanchosk]

I had to slightly adjust the code for AS5600.
It's still dirty (e.g. no protection, the overturn is VERY rough, ...) but it works already and could be a good starting point for others.
For now I removed the step/dir code as I am still testing it.
I'm not looking to merge it with your codebase, I'm more interested in your comments to be honest ;)

[sanchosk]

Well, I finalized my fixes for the code of ATtiny85. It works great now on all 3 axes. And is tested with TB6612 and A4953, works OK with both.
I added the minSearch code. What this does is it searches for the minimum position therefore eliminating the need of min switch. I tested it on all 3 axes, works OK. I added a "safety zone" - as the minPoint is found, the code sets it as -75 - to avoid push to the axis wall or end whenever there is Gcode pointing to 0 value on the axis. On my printer this means the real 0 position will be ~2mm from the actual minimum, which works OK for me.
Another add-on is the introduction of stepKoef - as my Z axis has VERY high resolution, it was painful for both RAMPS and the Tiny to process so many steps - so I divided the steps in RAMPS config and introduced the multiplier here.
I used your hint for DIRECT/REVERSE pid calculation to avoid unnecessary calculations.
So now everything works:

• determining the motor direction and compensating for it
• finding minimum movement speed
• using the minimum speed to find the minimum value of the axis

All the variables now use LONG instead of INT, so no more problems with overflow :)
Hope at least parts of this code will help you.