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amminadabz / Synharmonium

A new kind of musical instrument.
GNU General Public License v3.0
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Firmware: no keypress recognition #2

Open amminadabz opened 1 year ago

amminadabz commented 1 year ago

When the prototype keyboard is connected, the serial monitor shows output from the loop counter function, but none from any keypresses. Connectivity has been thoroughly checked once, and I'm liable to do it again, but it's safe to assume there's an issue in the firmware considering that I wrote it.

amminadabz commented 1 year ago

I just found something strange.

I connected an LED to one of the column pins to see whether the MCU was sending scanning voltage, and it was. Then I put it in parallel to a row pin to see if the switches were returning that scanning voltage when pressed, and they were. Then I noticed that whenever I added the led to a row pin, the serial monitor showed keypresses for all the keys on that row, and the inverse when I removed the LED.

So, apparently, this whole time the key matrix library has been designed to work with a pull down resistor rather than reading return voltage. The bass keyboard circuit is modeled after mechanical keyboards, so it was not designed for pull down resistors.

Now, either parts of the library will have to be rewritten or one meant for a keyboard-style circuit will have to be found.