No, not really a Harry Potter spell. :)

Actually, I claim little originality for this design - it's a blatant rip-off of Peter's new Pico Computer 3 but done in my style. :) At this stage it's just a mental exercise to see if it's possible. I wouldn't call it complete or even likely to work! Certainly don't bother with this version if you want GPIOs - there wasn't room.

Designed to fit into a £1.30 case from AliExpress. It may fit, I don't know because I've not tried it. :) The PCB is my first real 4-layer design and JLCPCB are quoting $7 for five so it doesn't seem to be straining their resources much.

AliExpress case

Just for fun it uses a sub-miniature relay for the USB switching. Hold down BOOT and plug the USB-C into the side to install the firmware. Plug the USB-C into the rear for normal operation. I like clicky relays.

No SMD smaller than 1206 apart from the micro SD card (sorry about that, there wasn't enough room for a full size socket).

Nice. A bit hard for me to follow totally. What is FE11SX4?

No PSRAM? That's a must-have for me for a do-it-all PCB.

It's a 4-port USB hub module. No trimmings like indicator lights or overcurrent protection though. Info here. It uses 2mm pitch headers on weird centres.

The PGA2350 includes 16MB flash and 8MB PSRAM on GP47. Info here. You have to solder your own headers on though!

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It's a 4-port USB hub module. No trimmings like indicator lights or overcurrent protection though. Info here. It uses 2mm pitch headers on weird centres

Wow, that's almost wacko enough to make me never want to use it.

It took me a bit of careful measuring to put together a usable SL6 macro. :)  I couldn't find an official drawing, but IIRC there is a KCAD drawing for it. There aren't many choices.