Reading Digital caliper with Arduino

[EdK]

(08-28-2015, 02:36 PM)arvidj Wrote:

(08-28-2015, 11:07 AM)EdK Wrote: Clever solution. He's using the A/D inputs thus not needing the level shifter circuitry.

Ed

I would think that having a level shifter at the scale end might offer an enhanced level of noise resistance. But careful placement and shielding might take care of that issue when taken off the electronics bench and put in the shop.

I agree and I would never connect directly from the caliper to the Arduino like he did. Any ESD is going to blow out the Atmel chip rather than a 35 cent transistor. Ideally, opto-isolators should be used but transistors are cheaper and easier to replace.  

Ed