Customized laptop keyboards are available all sizes and styles. At their core, they’re a matrix of switches related in a matrix {that a} microcontroller scans. The TypeBoy is an ergonomic mechanical keyboard packing a singular microcontroller design. The mission creator, Stu (AKA FlatFootFox), designed an nRF52 module referred to as the TypePak to suit right into a Sport Boy Advance cartridge that plugs into the keyboard!
“Your eyes do not deceive you: This can be a keyboard that wants a Sport Boy Advance cartridge to operate.” — FlatFootFox
Naked TypeBoy keyboard with TypePak plugged in (📷: FlatFootFox)
This mission has a number of items: the keyboards and the microcontrollers. The cut up keyboard known as TypeBoy. Every has 29 keys wired in a matrix, which means the whole ergonomic keyboard has 58 keys. TypeBoy doesn’t have any intelligence. As an alternative, it has a socket that mates with a Sport Boy Advance-style cartridge. The socket’s routing makes it reversible, so a single PCB works for the keyboard’s left or proper half.
TypePak comprises the microcontroller and appears like a Sport Boy Advance cartridge. Inside is a customized PCB with a Seeed Studio’s XIAO nRF52840 board. The Nordic Semiconductor nRF52840 helps Bluetooth Low-energy (BLE) and 5.0. A Sharp LS011B7DH03 Reminiscence-In-Pixel (MIP) LCD shows standing info like Bluetooth sign power and battery life. The enclosure has sufficient house to accommodate an 80 mAh LiPo battery.
Left and proper keyboard with TypePaks (📷: FlatFootFox)
The XIAO’s type issue has restricted GPIO pins. So FlatFootFox added a 74HC595 shift register for extra IOs. The result’s that TypePak’s 32-pin edge connector has all the XIAO’s pins damaged out and sufficient IOs to scan the keyboard matrix.
The TypePak runs an open supply firmware for keyboards referred to as ZMK. It’s a Zephyr-based RTOS with vital keyboard options. For instance, it has built-in assist for low-latency BLE, cut up boards, macros, and far more. You’ll be able to see the intensive ZMK function checklist right here.
Whereas the microcontroller runs the inventory ZMK firmware, transferring TypePak from one keyboard to a different isn’t a straight plug-and-play swap. If the keyboard matrix differs, it’s essential to re-flash the firmware first. Regardless, TypePak is a compact answer for including logic to a customized keyboard design.
TypePak PCB with XIAO nRF52840 (📷: FlatFootFox)
The boards and elements wanted to construct one are comparatively cheap. The KiCad design recordsdata, gerbers, and ZMK configurations are within the Typeboy and Typepak GitHub repository. FlatFootFox has supplied intensive construct notes in this weblog put up.