Last month, I described the numerous features of Keyboardio's Model 01 (Figure 1) [1]. The keyboard's ergonomics, customizations, and aesthetics are joy enough for many users, but these features are just the most obvious. The Model 01 is open hardware, which means that you can program everything in the firmware to your liking, rearranging the keymap and the LED backlights and adding plugins; you are limited only by the memory of the keyboard's two ATmega32U4 Arduino microcontrollers. In the process, you can learn some of the basics of programming Arduino C for use with other devices [2], as well as some of the logic behind other open source keyboards that use some of the same code, such as those offered by Input Club.

Before you can reprogram the firmware, you need to set up the Arduino IDE and the Model 01 firmware [3]. Begin by downloading, uncompressing, and installing the Arduino IDE, following the instructions on the Keyboardio wiki. These instructions are lengthy, but each step is simple in itself. Note, though, that there are some special instructions for some distributions. In particular, the ones for Ubuntu also apply to Debian, and, I'm guessing, most Debian-derivatives as well.

Next, follow the instructions to download and install the source code for the Model 01 firmware [4]. The procedure places a copy of the firmware in $HOME/Arduino/Model01-Firmware called Model01-Firmware.ino – a sketch, in Arduino jargon. This file can be edited in the Arduino IDE or any other text editor. When you are finished editing, the file must be flashed on to the keyboard, just as a firmware update from Keyboardio would be. A Keyboardio firmware update would overwrite your edited file, so either change its name or back up a copy of your changes as a reference. If you run into difficulties, you can restore the default firmware and try your customizations again.

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