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Old 01-21-2017, 03:48 PM   #3013 (permalink)
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OK, here are the DIFF-files for my reverse function hack.
I used source code from Jan-06-2017.
Paul, may i attach that version of source code here?

It uses the ICSP header for input and the LED output as an indicator.
No settings for reverse-amps, so you get full power backwards.
Use this at your own risk!!

I forgot to add the resistance...
Put resistor values as suggested here, it worked good for me:
Originally Posted by thingstodo View Post
I would add a couple of resistors on the board, and one in series with the switch, to limit the max current into the micro.

Perhaps a 22K from Vcc (whether that is 5V or 3.3V) or your top trace on the board to the PIC pin or middle trace on the board. A 10K resistor from the PIC pin, or middle trace on your board, to Gnd, the bottom trace on your board. This one is shown as 'some resistor. That sets up a voltage divider for about 1/3 of Vcc on the input pin, which should read as 0 or OFF.

The switch would go in series with a 2K2 resistor - top trace to your switch .. green wire ... which is now wired in parallel with the 22K resistor. That sets up the PIC pin for about 85% of Vcc and should read as 1 or ON.

These resistor values are ones that I typically use. They limit current under 3 mA and are easy to buy. I didn't look up the specs on the PIC, but I don't expect any issues with low current into the PIC pin.
This was a comment to this:

Making it:

Last edited by motorulf; 01-21-2017 at 03:56 PM.. Reason: adding more stuff
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