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WSAL20051 – Pico-CapTouch-ePaper-2.9/en

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Documentation notice: This technical documentation was independently rewritten from an archived supplier source. Check technical details and commands against the product version and manufacturer documentation before use.

Summary

Technical guide for the Waveshare 2.9-inch e-paper touch module for Raspberry Pi Pico.

Related products at JW Tech

Technical overview

  • Resolution 296 × 128 pixels; black/white with four-grayscale support on full refresh.
  • Interface: SPI (CPHL=0, CPOL=0, SPI0); touch via I2C at address 0x48.
  • Operating voltage 3.3 V / 5 V; standby current below 0.01 µA.
  • Full refresh takes about 3 s; partial refresh about 0.6 s; refresh power typically 26.4 mW.
  • Capacitive touch with up to 5 touch points on a toughened glass panel.
  • Pico pinout: DIN→GP11, CLK→GP10, CS→GP9, DC→GP16? No—DC→GP8, RST→GP12, BUSY→GP13; touch: TRST→GP16, INT→GP17, SDA→GP6, SCL→GP7.
  • Pixel encoding: 1 bit per pixel (0 = black, 1 = white); 1 byte represents 8 pixels.
  • Four grayscale is implemented using two image layers; register values 0x24 and 0x26 together define each pixel's gray level.

Commands and examples – verify before use:  

cd ~ && wget https://files.waveshare.com/upload/5/5a/Pico_CapTouch_ePaper.zip && unzip Pico_ePaper_CapTouch.zip -d Pico_ePaper_CapTouch
git clone https://github.com/waveshare/Pico_CapTouch_ePaper
mkdir build && cd build && export PICO_SDK_PATH=../../pico-sdk && cmake -DPICO_BOARD=pico -DPICO_PLATFORM=rp2040 .. && make -j6
cp epd.uf2 /media/pi/RPI-RP2/
sudo apt upgrade thonny

Notes and version constraints

  • The listed refresh times and power figures are experimental measurements; actual values may vary.
  • A brief flicker can occur during a full refresh – this is normal.
  • After waking from deep-sleep mode, the display must be re-initialized and the screen cleared first to minimize afterimages.
  • Four-grayscale functionality works only on full refresh; partial refresh does not support grayscale.
  • E-paper reflects ambient light and needs no backlight; direct sunlight is not supported.
  • If the program stalls on “busy”: check wiring, SPI baud rate and mode settings.
  • The provided GitHub link references a repository named Pico_CapTouch_ePaper; verify the exact repository name in a browser before cloning.

Source and revision record

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