Read out of HW v0.1

A project log for DIY Digital Caliper

I design my own digital caliper based on STM32F103 blue pill.

dimitarDimitar 04/11/2024 at 13:530 Comments

Hello all,

I have cut the trace going from the sense pad to the ADC pin of the STM32F103 to be able to get a good reading with a scope. 

When I aligned the T scale with the "positive" pads I get the following signal on the scope.  

If I move to one side I get this

and when I move it to the other I get this

So the sine wave is being shifted from one side to the other, signals are being generated the way they are supposed to.

This is great news! This means that we have successfully validated the footprints for our caliper. 

Next step that (I have overlooked on HW v0.1) is signal conditioning. We will need to shift this signal up since is going to -300mV and also would be nice to add a splash of amplification. 

On that note if someone has any suggestion how to do that, please write me a comment or drop me a message!