Not being one to just stick a wet finger in the air, I want to set my driver current ‘correctly’ – that being to measure the motor driver vref and adjust the pot in line with the stepper and TI’s recommendations.
Normally I would stick one probe in gnd and one on the top of the pot, but these are plastic pots, so non-conductive. Is there a vref pin or via somewhere I can read off? (I checked the driver power schematic – couldn’t find it… but then, I couldn’t find the pot, either 🙁 )
P1 and P2 are the pots for, I think, motors 1 and 2.
I think the wipers of the pots are what you are looking for as they connect to the driver Vref, pin 8.
There is no layout diagram that I am aware of, likely finding a via, etc would just be luck.
If you are read good at soldering, you could add small wires for clip leads, I suppose.
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