Implements an input driver utilising the MPR121 Touch IC and is compatible with common MPR121 keypad PCB's.
- Implements a "candybar" phone style 12-key keypad
- multiple taps to rotate through the character set
- longpress for navigation keys
- keymap to allow arbitrary routing of MPR121 pin to button configuration
- extendable to other key functions
- Integrates with the existing kbI2cBase implementation
- Works with CannedMessageModule Freetext mode
- Can be used with common MPR121 boards, such as https://www.amazon.com/MPR121-Capacitive-Keyboard-Buttons-Sensitive/dp/B083R89CHB/ref=sr_1_6
- Of use for PCB based radios, where some form of low surface area low component freetext input is required, but also without consuming too many IO pins.
- Tested on a T3S3 connected to Wire1 (Second) interface.
- Demonstration of functionality: https://youtu.be/UI6QP6nGvhY
