Hmm actually, FAK could be extended to CH582. It would have to be a complete rewrite on the hardware code, but I could keep the Nickel config mostly compatible between CH55x and CH58x.

You just gave me an idea. Sounds like I can make a FAK spec and then there’d be compliant hardware-specific implementation for different chips 🤯

Yep, and I think they’re even working on dongle mode. They call it “triple 2.4G” on the readme.

Looking good! DM’d you

Thanks! No CH55x chip supports Bluetooth so it’s USB only. I thought of possibly adding a Bluetooth module, but that’s almost always a SoC and you’re much better off using that as the main (and only) microcontroller instead.

There’s this: https://forum.arduino.cc/t/jdy-23-bluetooth-module/672581 Could work as a “dumb” BT module but even so, it can’t do HID over BT directly so have to translate that to HID with another chip. Not so power efficient too.

Basically, I’ve been through this path and it always led me to: just use one MCU with BT. Fortunately, CH582 is a cheap one. RISC-V with BLE. And it’s been recently ported to QMK as well: https://github.com/O-H-M2/qmk_port_ch582

Cool! Though CH58/9x series might be better for efficiency because it’s Bluetooth 5. CH57x is BT 4.

And QMK has already been ported to CH582 but personally haven’t tried it yet. https://github.com/O-H-M2/qmk_port_ch582

Go for it! I have a schematic in mind but too lazy to learn KiCad. Would love to help out :)

Also, there’s a commercially available CH552T dev board for about a dollar. I actually use this for development: https://www.aliexpress.com/item/1005004141926425.html

Even cheaper if you buy just the chip. Just add a USB connector and two capacitors then that’s it. No crystal, flash, etc. needed. A CH552G goes for about 30 cents: https://www.aliexpress.com/item/1005003402478164.html

Thanks! Plate is aluminum. I brushed it with sandpaper and applied some metal polish for a shiny brushed look.

I got the case from JLCPCB with their cheapest resin (8111X). Got it for only one dollar including shipping lol thanks to the $7 coupon you can get from sharing 3D models. Out of the box, fairly sturdy. It was semi-translucent white but a bit yellowish and ugly, so I spray painted it.