#PCB to interface the CYD to the digital calipers
The calipers operate at 1.5v so this is required to convert this to the 3.3v of the CYD. It is a very simple circuit which uses a single transistor per data pin, I used my CNC router to cut a PCB but you could easily just build this on some strip board etc. I have seen others use the level shifters from eBay but I could not get mine to operate with the 1.5volts.
I think if I were building another one I would seriously consider using a AA battery to provide the 1.5v for the calipers rather than using the 5v power rail, this would get round a lot of potential issues with noise on the power line upsetting the calipers and issues of them not starting up correctly when the power is first applied.
The calipers are linked to the CYD via a ribon cable soldered directly to the ESP32 module (the 3 colour led needs to be removed).
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