My First Charlieplexed Display

Published on 2018-08-13 in PewPew Standalone.

Once I got my matrix-driving code working on the PewPew 8.0, it was just a question of hacking a tri-state gpio pin switching function and some trivial modifications to get it to work with a charlieplexed display. At least it seems so, because it looks like it’s working:

There is a slight problem with brightness — they are way too bright now to distinguish individual shades. Of course my phone camera got overloaded and did something funny with the colors, to the naked eye they are all blindingly red. I will need to tune the PWM somewhat.

I’m powering it with a bench power supply for testing, because the poor little coin cell only lasts a few minutes with the display on at full power — even though the bench supply claims it’s only drawing 20mA total.

We will see what I can do with it, but it definitely looks promising.