Don Kiser's HX-2023 Packs a Raspberry Pi 4 Into the Shell of a Classic Epson HX-20 Notebook Computer
Using spares gathered over years of refurbishing HX-20 units, this stealth cyberdeck packs in the power.
Controls engineer Don Kiser has taken a classic Epson HX-20, one of the first truly portable notebook computers, and turned it into something a little more modern — powered by a Raspberry Pi 4 single-board computer (SBC).
"It started with just one Epson HX-20 won at auction," Kiser explains of the project's roots. "After purchasing several and refurbing them I had a few spare parts. Why not do something interesting with it? This is my project to re-imagine the Epson HX-20 into a sort of retro cyberdeck for 2023."
The Epson HX-20 launched in 1982 as the first commercial battery-powered notebook-form-factor computer. Built around a pair of Hitachi 6301 CPUs running at 614kHz and with 16kB of RAM expandable to a generous 32kB, the device proved popular with those who wanted to work on the go — particular thanks to a built-in receipt-style printer and full-size keyboard.
Those specifications are a little tame by modern standards, though, which is where Kiser's sleeper build comes in. The chassis' internals have been entirely replaced, now boasting a Raspberry Pi 4 Model B with 8GB of RAM — a mere 524,288 times more than the original stock HX-20 — and a 500GB SSD for storage. There's a dedicated soundcard, a PiSugar S battery pack, and an Adafruit KB2040 Kee Boar — the latter using a Raspberry Pi RP2040 microcontroller to adapt the HX-20's original keyboard for USB use.
Not all the modifications are purely internal, either. The HX-20's original single-colour 120×32 display, capable of showing the user four lines of just 20 columns width, has gone, replaced by a Waveshare 4.3" color touchscreen display connected to the Raspberry Pi's MIPI Display Serial Interface (DSI).
"There's no 3D printing here," Kiser notes of the case modifications. "Everything was done by hand using various Dremel tools, 'Xacto' knife, and lots of sand paper. [The] LCD bezel was custom made from expanded PVC plastic board. The rear and side plates are made from acrylic sheet."
Kiser's project isn't quite complete yet, though: he's also looking to get the HX-20's original printer up and running with the Raspberry Pi. "The printer is currently on [a] breadboard," he explains.
"I've got a small Arduino to handle printing. Right now I've got it working up to the point to put dots on the paper. It runs the motor, counts the pushes, goes to stability and sends the signals to print but the solenoids to fire. Once I get the printer working I'll think I'll set it up on the Pi as a serial printer."
Kiser's full project write-up is available on his Hackaday.io page.