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Firmware Quirks

A project log for ShortyPen (by Jiri Dobry)

An ultra-low resistance 3-wire Kelvin portable ohm meter

criptastichackerCriptasticHacker 09/23/2024 at 00:400 Comments

When I first powered this up, the screen came on for a couple of seconds, and then shut off.

Only after translating the manual and picking my brain did I discover that this is by design!

The unit doesn't give any indication of this, but it needs to be calibrated before first use.  So the person has to hold down the Button 1 for a few seconds to go into the calibration mode.

Then the probes need to be attached to for resistor values (ideally at 0.1%) - 0 ohm, 1 ohm, 2 ohm, and 8.2 ohm.   You'll need to assemble a test rig for this.

That's as far as I've gotten so far.  The unit is working now, so I passed it onto my friend. He said he would let me know later of the updates on using the firmware and squashing any software bugs!  Personally, I would like to see some text added to the screen on boot that says "need calibration" or something like that.  I thought I had broken the power circuit!

I also tried to download most of the documentation that is stored in the cloud on EasyEDA - which is not in the original Git repository from the author.  Gerbers, board layout PDFs, etc.  I'll try to upload those later.

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