68kMLA Classic Interface
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| Click here to select a new forum. | | MacDVI - OSS Pico 2 based TTL to DVI video converter! | Posted by: arroz on 2026-05-10 09:58:02
Hi everyone!
Just announcing that a few days ago I published MacDVI, the source and documentation for a small project I've worked on on my free time as part of moving my Mac Plus to an LCD instead of the CRT: https://codeberg.org/arroz/MacDVI This is a DIY project, that anyone can build with a Pico 2 and a level shifter (or a few resistors if you're lucky).
It uses a single Pico 2 to sample the video and outputs it to a 1024x768 DVI (HDMI compatible) screen. Since that resolution is twice the Mac's one (with black bars on top and bottom to compensate for the 384-342 height difference) the scaling is pixel perfect. It works on the 128k, 512k and the Plus. Other B&W compact Macs can probably be made to work as well with a few adjustments in the software, but I don't have any of them to test, unfortunately.
I have written extensive documentation since I would love it to be used as learning material for people getting into electronics and/or restoring these wonderful machines.
As far as I know this is the only converter out there that outputs a digital signal (not VGA), aside from RGBtoHDMI and variants. The motivation was developing something that could be built on a much less expensive, and readily available hardware. Since DispHSTX could do the HDMI part at the resolution I needed, and I knew the Pico could sample signals fast enough (as I have sampled them using the Pico-based Dr. Gusman logic analyzers) it was just a matter of putting all the software together. 😃 It's my first project with a Pico, I loved working on this and almost screamed the first time I saw those PIO state machines sampling the image of my old Plus perfectly.
I hope you find it useful! 🙂
Regards,
Miguel Arroz | Posted by: Byrd on 2026-05-11 02:58:07
Thanks Miguel, nice project! Also excellent for testing these boards | | 1 |
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