CharaChorder Engine

Welcome to the Official CharaChorder Engine guide. You can select the links below to navigate to the topics that you find most relevant.

CharaChorder Engine

CharaChorder Engine is a multichip module that enables you to build your own CCOS powered text entry device. If you are interested in learning how to utilize CharaChorder Engine, please visit the CharaChorder Engine Discord channel and ping Riley Keen or Matt Swarts.

Pinout Diagram

CharaChorder Engine pinout table


The Engine is designed primarily to work with a MCU to receive inputs (through UART and later I2C or SPI), process the chording logic, query the onboard chordmap library, and output the results back to the MCU (again over UART and later I2C or SPI). However, the layout of the Engine exposes USB pins, which could have a future capability for direct USB HID output. This could be limiting for some developers, as they may want to control their HID reports themselves through their MCU.

Physical footprint

Here is a zip file that contains a step file as well as KiCad files for the CharaChorder Engine that can be used to aid you in the design of your CCOS powered keyboard.

Communicating with Engine Devices

Like other CCOS powered devices, any device with CharaChorder Engine can use the full power of the Serial API.