Theoretically supports all nRF51 series MCUs, built-in 3 micro-snow 4.2 inch e-ink screen drivers (switchable), also supports custom e-ink screen to MCU pin mapping, supports sleep wake-up (NFC / wireless charger).

Supported Devices

The hardware is hacked from a 4.2 inch e-ink price tag available on e-commerce platforms, you can click here to buy, supports both black and white dual-color and black, white, and red tri-color versions.

Black and White Dual-Color Version

MCU: nRF51822
RAM: 16K
ROM: 128K

Driver: UC8176 (EPD_4in2)
Screen Pins: 0508090A0B0C0D
Coil Pins: 07

Black, White, and Red Tri-Color Version

MCU: nRF51802
RAM: 16K
ROM: 256K

Driver: UC8276C (EPD_4in2b_V2)
Screen Pins: 0A0B0C0D0E0F10
Coil Pins: 09
LED Pins: 03/04/05 (three LEDs, any one can be used)

The default driver and pin mapping are for the black and white dual-color version, other versions need to switch drivers and modify pin mapping.

Upper Computer

Address: https://pengwon.github.io/epd42/

Scan the QR code above to join the WeChat group for more information.

Compilation Targets

nRF51822_xxAB: Used to compile nRF51822 firmware, with built-in black and white dual-color version configuration
nRF51802_xxAA: Used to compile nRF51802 firmware, with built-in black, white, and red tri-color version configuration
flash_softdevice Target: Used to flash the Bluetooth protocol stack (only needs to be flashed once)

You can use J-Link or DAPLink as the programmer (you can use RTTView to view RTT logs).

Flashing Process:

If you do not modify the code, it is recommended to download the binary firmware from Releases for immediate use.

Erase all (if Keil cannot erase, try using the programmer's upper computer software to erase)
Switch to the flash_softdevice Target corresponding to the MCU, do not compile, just download (only needs to be flashed once)
Switch to the Target corresponding to the MCU, compile first, then download

Acknowledgements

This project is forked from EPD-nRF51, thanks to the original author for sharing and contributing.