Keybytes Puts a RISC-V Microcontroller in Every Single Key, Then Snaps the Keys Together With Magnets and Pogo Pins

The idea started with a complaint. “I had always wanted to make a keyboard but I didnt want to be locked into just one design,” the maker, GitHub user notaroomba, wrote in the project journal in March. “I searched online and couldnt find it anywhere so I decided to make it myself.” The Register identifies him as Nathan Alspaugh, a first-year aerospace engineering student at MIT, and says he’s put about 100 hours into it.

There are two kinds of board, and both are the size of one key. The “Keybit” is “a single key with a Cherry MX switch and a CH32V003,” the README says. “Every side has pogo pins for 3.3V, GND and I2C so it can connect to the keyword or to other keybits.” The “Keyword” is the brain, two PCBs stacked into the same footprint, carrying the STM32WB55, a ceramic Bluetooth antenna, USB-C, a charger for a single-cell LiPo and 2 MB of flash to hold the keys’ firmware.

That flash is there because the main board is designed to program the keys itself, over three pogo pins on its top edge. In the repo today, that part is still a plan: the Keyword’s firmware “just cycles the status RGB LED,” and there’s no key firmware posted yet.

Getting the hardware right took most of the year. On October 21 the magnets turned out too weak to hold against the spring of the pogo pins. The case went through twelve versions, which he calls “the most overengineered thing ive done.” On the night of October 24: “And then I put it all together and it finally works!!!”

The parts list is where the idea gets expensive. The prototype order on the repo’s BOM comes to $472.77. A Keybit board costs a couple of dollars, The Register reports, a Keyword about $30, and factory assembly added $69 and $203. For a full-size board, “2 keywords and like 110 keybits,” he priced it “around $900 assembled, almost half of that being the pogo pins lol.” If he ever builds one, he told The Register, he’ll buy the parts separately and solder them himself.

He’s thinking past the prototype. “I am thinking about selling them in the future once the designs are improved and finalized,” he told The Register, and “I’d probably make more key varieties, like ones that have a fingerprint sensor.” Whether a key with a fingerprint reader still snaps into the same 19.05 mm square, he hasn’t said.

Modular keyboards keep coming back because people’s hands, desks and jobs keep changing faster than their keyboards do. What’s new here is how cheap a whole computer per key has become; the cost that’s left is the connectors, and that’s where the next version has the most to win. Expect the pogo pins to be the first thing a future revision trims.