Before HDMI and DVI there was VGA, and before that? TTL RGB, in which instead of analogue voltages, the connector carried TTL logic voltages. TTL monitors used to be ten a penny because nobody wanted them in the VGA era, but the decades have not been kind to the TTL video aficionado. Stuck with a TTL card and no compatible monitor? Never fear, for [Charlysan] has your back with a TTL-to-DVI converter using an RP2350. The PIOs are used to sample the TTL input to a framebuffer, and the rest of the 2350 does the DVI magic using PicoDVI.
It requires a bit of level shifting hardware, which at minimum can be a set of resistors, and it targets the Waveshare RP2350-PiZero which comes with a handy ready-made HDMI socket. There’s a USB serial terminal to manage the thing, for which there’s even a TK GUI script.
This is the type of project which may never be center stage, yet performs such a vital function that it becomes indispensable. It’s not the first such project we’ve seen, a previous one did the same for VGA.
