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CHAPTER
FIVE
THE KEYBOARD
The keyboard is a row/column matrix scanner with anti-ghosting diodes on each switch. Each row and column
is connected to one pin of the ATMega32U4 8-bit microcontroller. This microcontroller runs a firmware based
on LUFA. This converts the scanned out keycodes to the USB HID protocol.
5.1 Firmware
You can find the Reform keyboard firmware in the source folder "reform-keyboard-fw".
To modify the scancodes of the keyboard matrix, edit the file Keyboard.c and rebuild the firmware by typing
the following command in a terminal:
make
To be able to flash the firmware to the keyboard, the ATMega has to be in a special mode where it identifies
as an "Atmega DFU bootloader" USB device. This is achieved by shorting the pins HWB and GND with a
jumper and then briefly shorting the RESET pin to ground.
The RESET pin is pin 2 of J1, pin 1 is GND.
HWB and GND are pins 3 and 4 of J3, respectively. Start counting at the "J3" label.
The keyboard will reappear as a Atmel DFU bootloader USB device. You can then upload your new firmware
by executing:
./flash.sh
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