A graphical text editor in uLisp


Hello all,

I’ve been having a lot of fun with uLisp lately, using it as the “operating system” of my homebrew computer (I previously shared a link to this project in Adafruit nRF52840 Express + Sharp memory display).

I have now created a text editor in uLisp which I’ve named “Typo” - this is actually the second version. It is still very bare-bones, but I think it is now in a state where it could be useful to someone else - although perhaps mostly as inspiration or a starting point, as key codes, number of displayed lines, etc. must be adapted for another input mechanism / display.

Link to the code is below, but first I thought I’d post a short demo video, showing me adding a very simple feature to the editor while using it. In the name of honesty (and laziness) I have not edited this video so please be patient with me as I correct my typos and forget the key code I just checked!

Demo video: https://youtu.be/W_9N8apYEjc

Source code: https://github.com/andreer/PotatoP/blob/main/lisp/typo2.lisp


Nice! How did you interface the keyboard to the nRF52840 board?


I changed the board out for a Sparkfun Artemis ATP, which has a lot of GPIO pins, desoldered the connectors for the keyboard matrix and hooked them up. So I am scanning the matrix directly. It’s less complicated than interfacing with the existing USB controller, lower latency and is vastly more power efficient. Which is a focus of the project, the whole system only uses 1-2 mA while running ulisp code and updating the display.