Looks a bit like the Datahand, been using those for the past 20 years.
One difference is that the Datahand also has keys on the left and right of each finger for a total of 5 keys on each.
One difference is that the Datahand also has keys on the left and right of each finger for a total of 5 keys on each.
One funny consequence of using IR switches is that direct sunlight can trigger them. I've had a few occasions when I was greeted by a screenful of repeated characters when I returned to my desk.
Those Hall effect switches and design are amazing.
This post inspired me to modify my own in a very similar fashion: https://geekhack.org/index.php?topic=12212.0
Teensy++: https://www.pjrc.com/store/teensypp.html
And this is the firmware I wrote and still use: https://github.com/imarko/dhteensy
I think there might be some better versions out there but I wrote this to work just the way I wanted so never bothered with anything else.
I don't have one to sell unfortunately, my spares may need to last me a lifetime :)