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I got a ZX Spectrum emulator working on my ESP32-TV board (along with a bunch of other ESP32 boards). And using the QWIIC connector I was able to hook up a Wii Nunchuk.

ZX Spectrum Emulator

It was pretty cool - and I was all set to do a video on it - but then PCBWay announced their new full color silk screen service and I just had to give it go.

The good old ZX Spectrum keyboard seemed like the perfect thing to recreate.

The ZX Spectrum

Using the same layout as the original ZX Spectrum in a matrix arrangement we need 8 rows, each with 5 columns.

ZX Spectrum Keyboard Membrane

For a touch matrix that means we need 13 touch pins. Initially I thought this wouldn’t be possible as the ESP32 only has 10 touch pins. But the S3 has 14 pins - so it was all systems go and I’ve ended up with a PCB that looked something like this:


And with the full color silk screen printing we ended up with this thing of beaty!

A thing of beauty

The display that I designed for is pretty small - as you can see from the tiny picture! But I left an expansion header on the board to hook up a bigger screen.

The big screen

It works really well - and I think a lot of people are going to want this. It’s not quite ready yet, so I’ve set up another newsletter (you can’t have too many newsletters!) for people who are interested in buying one to sign up for. I’ll put regular updates out on this as I don’t want to spam people who aren’t interested…

So, if you think you’d like your very own ZX Spectrum - sign up to the newsletter above!

I’ll continue to work on the project - and I’ll post videos to the channel and posts here as I make progress. But there will be more fine grained updates on the other newsletter for people who are really interested.


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ESP32-S3 ZX Spectrum - Full Color Silk Screen is really cool! - Super stoked to share this creation – an ESP32 ZX Spectrum emulator! Although it's still very much a proof-of-concept, it's looking pretty rad. I've got the classic games like Manic Miner, and yes, you can program in basic too! In perfect Sinclair fashion, I'm planning on selling this key piece of nostalgia for just £99. Work still needs to be done before the production phase, but rest assured, I'm meticulously working out the kinks, including tweaking the keyboard to ensure even better user experience. And on the technical side - a single ESP32S3 runs the show and we’ve multiplexed the keys exactly like the OG Spectrum. It's been great fun designing this piece of kit with the new full color silk screen printing from PCB way. Stay tuned for further updates!
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HELP SUPPORT MY WORK: If you're feeling flush then please stop by Patreon Or you can make a one off donation via ko-fi
Want to keep up to date with the latest posts and videos? Subscribe to the newsletter
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Chris Greening


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A collection of slightly mad projects, instructive/educational videos, and generally interesting stuff. Building projects around the Arduino and ESP32 platforms - we'll be exploring AI, Computer Vision, Audio, 3D Printing - it may get a bit eclectic...

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