[Evan] was perusing his local thrift store when he found a beautiful IBM Model M 122-key keyboard made in 1987.
“This is my keyboard, there are many like it, but this one is mine.”
~The Typist’s Creed
In [Evan's] case, this might actually be the only one like it still in use today. An idea formed in his head. What if he took this ancient keyboard, gave it a USB driver, and customized the keys on a hardware level to do exactly what he wanted.
The first step was converting it to USB. He’s using a Teensy 2.0 mostly because it is super inexpensive, and its able to act as a USB HID device. In addition to wiring up the keyboard to the Teensy he’s also added foot pedals that connect via 1/8″ stereo plugs — these kind of act like extra mouse buttons, allowing him to scroll through galleries left to right, add page breaks, and other macros to increase efficiency.