ZX Spectrum Projects – HD Video output

October 28, 2019

I’ve neglected my retro computer collection for a while now, so recently I’ve been dusting off my collection, starting with the ZX Spectrum to start some new projects with them. Whilst I have a few that need repairing I quickly got distracted into wanting to make a cool project for them.

Getting the Speccy to work with modern TV’s is becoming more of a problem. I’ve made composite video modifications to my Speccys in the past, I even made a small PCB that fits into space where the existing video modulator sits. But I want to see if HD / High Definition video was possible. By HD video I mean either VGA, DVI, DisplayPort or HDMI.

A quick web search found me Victor Trucco’s TK Pie. This is an interesting way of using a Raspberry Pi Zero to provide a High Definition (HDMI) video interface to the Speccy. It uses a mix of external hardware (CPLD) and the processing power of a Raspberry Pi Zero to capture writes to the Speccy’s video RAM and convert the pixel data into HD video via the Pi’s HDMI. There’s a similar project for the BBC Micro called RGDtoHDMI.

Here’s a link Victor’s web site and TK-Pie source code files

There are couple of useful reviews of TK Pie by GozdniJezek, Building TK-Pie by Victor Trucco

and martin@8bity, HDMI output for Sinclair ZX Spectrum – TK-Pie

Some more searching found me the next two devices. They don’t seem to be DIY projects but I thought they looked interesting.
Ben Versteeg at ByteDelight has ZX-HD: The story of the ZX-HD

and also Goran Radan with his ZX-VGA-JOY