The Stubborn Strobe

Well. That have been interesting 10 hours or so. I came to my studio today to have a bit of nonsense fun. Recently I started to fiddle around with some ESP microcontrollers, namely the ESP8266 and the ESP32, both fun and cheap devices (with pretty cheap devkits available at your typical electronics tinker stores) that have built in wifi capabilities.

To do something “useful-not-useful” with them, I started to look around for the most useless project I could do with them. And then, during a bit of cleanup at home, I stumbled over (not literally, luckily) my old 24 pin printer I used with my AMIGA in the 1990's. I thought to myself “how hard can it be to drive an old centronics interface from a modern microcontroller” and thought it would be a fun project to add a web api (as I have no interest in implementing one of the standard network printer interfaces) to an old 1990's printer.

So here's more or less what I did today:

(Images, schematics etc. will hopefully appear on a more upbeat post I will write after this project is “done”)

Update

I now replaced the level shifters I used with a simpler component – The ones I used are based on a TXS0108E by TI and are probably a bit too clever for their own good, or rather, built for a different purpose. I've now replaced them with a simple, transistor based level shifter and this now seems to work without any pull down.

Now I need to get back to the software :)