The Adafruit 2.13in Monochrome E-Ink Bonnet is a high-contrast, low-power display module designed for use with the Raspberry Pi. This E-Ink or electronic paper display (EPD) is ideal for applications where a simple, clear display is needed without the power consumption of a traditional LCD. Common applications include e-readers, signage, shelf labels, and any project where the display content changes infrequently.

• Display Type: E-Ink monochrome display
• Resolution: 212 x 104 pixels
• Display Size: 2.13 inches diagonal
• Interface: SPI
• Operating Voltage: 3.3V
• Dimensions: 65mm x 30.5mm x 6.8mm

1. Hardware Setup:

   • Align the Bonnet's GPIO connector with the Raspberry Pi's GPIO header and press down to connect.
   • Ensure the Pi is powered off before connecting the Bonnet to prevent any electrical damage.

2. Software Configuration:

   • Install the necessary libraries for the E-Ink display by running the following commands in the terminal:

     sudo pip3 install adafruit-circuitpython-epd
     sudo apt-get install python3-pil
     

   • Enable SPI using raspi-config:

     sudo raspi-config
     

     Navigate to Interfacing Options > SPI and enable it.

3. Displaying Content:

   • Use the Adafruit CircuitPython EPD library to control the display.
   • Create a Python script to initialize the display and draw text or images.

import digitalio
import board
from PIL import Image, ImageDraw, ImageFont
import adafruit_epd.epd as epd

spi = board.SPI() ecs = digitalio.DigitalInOut(board.CE0) dc = digitalio.DigitalInOut(board.D22) rst = digitalio.DigitalInOut(board.D27) busy = digitalio.DigitalInOut(board.D17)

display = epd.EPD(spi, ecs, dc, rst, busy) display.begin()

display.clear_buffer()

width = display.width height = display.height image = Image.new('1', (width, height), 255) draw = ImageDraw.Draw(image)

font = ImageFont.load_default() draw.text((10, 10), 'Hello, E-Ink!', font=font, fill=0)

display.image(image) display.display()

• Power Consumption: The E-Ink display consumes power only when updating the display content. To conserve power, update the display only when necessary.
• Partial Refresh: The display supports partial refresh, which can be used to update only a portion of the screen.
• Image Preparation: When preparing images for the display, ensure they are monochrome (1-bit) and match the display's resolution.

• Display Not Updating:

  • Ensure the SPI interface is enabled on the Raspberry Pi.
  • Check the wiring and pin connections.
  • Verify that the correct GPIO pins are being used in the script.

• Image Quality Issues:

  • Confirm that images are in the correct format (monochrome) and resolution.
  • Use dithering to improve the appearance of grayscale images.

• SPI Communication Errors:

  • Run ls /dev/spi* to check if SPI devices are available.
  • If not, reconfigure SPI settings using raspi-config.

• Display is Blank:

  • Ensure the display is properly initialized in the script.
  • Check that the power supply is adequate and stable.

Q: Can the display show grayscale images? A: No, the display is monochrome and can only show black and white pixels.

Q: How do I update only part of the display? A: Use the partial update functions provided by the Adafruit CircuitPython EPD library.

Q: Is the E-Ink Bonnet compatible with all Raspberry Pi models? A: It is compatible with any Raspberry Pi model that has a 40-pin GPIO header.

Q: How long does the display content remain visible after power is removed? A: The E-Ink display will retain the last image shown indefinitely without power.

For further assistance, consult the Adafruit support forums or the CircuitPython EPD library documentation.