Happy to hear the Arduino is not dead.
I tested it again on my bench and it functions properly.
I put the code in github
https://github.com/Boris4K/FastArduinoKeyboard

Look at my build in the show off corner. I added instructions for save state and load state.

Try reading this forum post
sparkfun

I modified the code after you saw my comment. Please use the new code.

I edited the code to include all the pins on the Arduino pro micro. I don't know if the extra unused keys might degrade the performance. I use the same code with a smaller arrays of 12 keys only. #include <Keyboard.h> #define BUTTONS 20 int keycode_arr[] = { 118, // PIN0 'v' 119, // PIN1 'w' 120, //...

Why didn't you get a 5 pin pot? It can be found on ebay.

I connected mine to a sony camera. Looks ok.

Thanks.
Can you make a review about your 3D printer?

You can buy an Arduino pro micro, it is cheaper.
I made a sketch for it, here.

Someone else has the same issue with OS X Sierra.
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