Stepstick MAX is fully assembled now. STM32 is running fine, but I haven’t gotten the driver to run yet. The charge pump pin shows a 100KHz square wave, so it is awake, but fault pin reads 0 despite the pullup resistor, so it’s not happy about something. According to the datasheet, the fault conditions are thermal (above 165C), undervoltage (VM below 4V) and overcurrent. But everything is cool, VM is 7.5V from my usual 2S lipo, and I can’t measure any shorts between the output pins and VM or ground or eachother. I also double checked that fault isn’t shorted to ground. No clue what’s wrong.
While testing on a Gooser4 the other day, I made a dirt cheap magnetic encoder for my NEMA23 steppers using a 3x4mm cylindrical magnet, two 49E linear halls and some 3D printed bits. It only clicks into some holes in the motor by friction, but stays on surprisingly well, and I’ll give it some hot glue for extra security. These motors run cool, so no worries about it melting.
So far I’ve gotten it to hold within ±1/800 of a revolution while harassing it, using some fancy lookup table calibration and direct angle PID without cascaded velocity PID. That’s ±5 micrometers with the 4mm ballscrews on my CNC, so maybe good enough, but hopefully I can improve it further.