1. Introduction
This document provides detailed instructions for the Waveshare 2.9-inch E-Ink Display Module. This module features a 296x128 resolution, an embedded controller, and communicates via an SPI interface. It supports partial refresh functionality.
E-Ink technology offers several advantages, including ultra-low power consumption, a wide viewing angle, and clear display visibility without requiring electricity. The display retains its content even when power is removed. These characteristics make it suitable for various applications such as electronic shelf labels, industrial instrumentation, and other low-power display solutions.
2. Features
- Display Type: 2.9-inch E-Ink (e-Paper) display module.
- Resolution: 296x128 pixels.
- Interface: SPI (Serial Peripheral Interface) for communication with various controller boards.
- Refresh Capability: Supports both full and partial refresh modes.
- Power Consumption: Ultra-low power, primarily consuming power only during display refresh cycles.
- Display Retention: Retains the last displayed content indefinitely without power.
- Viewing Angle: Wide viewing angle, offering clear visibility from nearly 180 degrees.
- Backlight: No backlight required; utilizes ambient light for visibility, similar to paper.
- Voltage Compatibility: Onboard voltage translator ensures compatibility with both 3.3V and 5V microcontrollers (MCUs).
- Development Resources: Online user manuals and example code are available for platforms such as Raspberry Pi, Jetson Nano, Arduino, and STM32.
3. Package Contents
The standard package for the Waveshare 2.9-inch E-Ink Display Module includes the following items:
- 1x Waveshare 2.9-inch E-Ink Display Module
- 1x Connection Cable (typically a 8-pin ribbon cable with female-to-female connectors)
Image 3.1: Package contents showing the 2.9-inch E-Ink module and its accompanying connection cable.
4. Specifications
Image 4.1: Detailed technical specifications of the 2.9-inch E-Ink module.
| Specification | Value |
|---|---|
| Display Size | 2.9 Inches |
| Resolution | 296 x 128 pixels |
| Display Color | Black and White |
| Grey Scale | 4 levels |
| Interface | 3-wire SPI, 4-wire SPI |
| Operating Voltage | 3.3V / 5V (compatible) |
| Full Refresh Time | Approximately 3 seconds |
| Partial Refresh Time | Approximately 0.6 seconds |
| Refresh Power | 26.4mW (typical) |
| Standby Current | <0.01uA (almost none) |
| Dot Pitch | 0.226 x 0.227 mm |
| Viewing Angle | >170° |
| Outline Dimensions | 89.50 x 38.00 mm |
| Display Area Dimensions | 66.89 x 29.05 mm |
| Item Weight | 0.352 ounces |
| Product Dimensions (LxWxH) | 7.09 x 3.94 x 3.54 inches |
Image 4.2: Outline dimensions of the 2.9-inch E-Ink module.
5. Setup and Connection
The Waveshare 2.9-inch E-Ink Display Module connects to a host microcontroller via an SPI interface. It features an onboard voltage translator for compatibility with both 3.3V and 5V logic levels.
5.1 Pinout and SPI Interface
The module uses a standard SPI interface. Refer to the pinout diagram below for connection details. Ensure correct wiring to your controller board (e.g., Raspberry Pi, Arduino, Jetson Nano, STM32).
Image 5.1: Onboard SPI Control Interface and Pin Descriptions.
- VCC: Power supply (3.3V/5V)
- GND: Ground
- DIN (MOSI): SPI Master Out Slave In pin
- CLK (SCK): SPI Serial Clock pin
- CS: SPI Chip Select, active low
- DC: Data/Command selection (High for data, Low for command)
- RST: External Reset, active low
- BUSY: Busy status output (High when busy)
5.2 Voltage Translator
The module includes an onboard voltage translator, making it compatible with both 3.3V and 5V logic levels from your microcontroller. This simplifies integration by eliminating the need for external level shifters.
Image 5.2: Onboard Voltage Translator for 3.3V/5V compatibility.
5.3 Initial Connection Steps
- Identify Pins: Locate the corresponding SPI, DC, RST, BUSY, VCC, and GND pins on your microcontroller.
- Wire Connections: Connect the module to your microcontroller using the provided cable or appropriate jumper wires, matching each pin as described above.
- Power Supply: Ensure your microcontroller provides a stable 3.3V or 5V power supply to the module's VCC pin.
- Software Setup: Download the relevant example code and libraries for your specific microcontroller platform from the Waveshare official website.
6. Operating Instructions
Operating the E-Ink display module involves programming your microcontroller to send display data and commands via the SPI interface.
6.1 Display Refresh Modes
- Full Refresh: Clears the entire screen and redraws all pixels. This provides the highest display quality but takes longer (approx. 3 seconds) and consumes more power.
- Partial Refresh: Updates only a specific area of the screen. This is faster (approx. 0.6 seconds) and consumes less power, making it suitable for dynamic content updates without redrawing the entire display.
6.2 Programming and Examples
Waveshare provides extensive online documentation and example code for various development platforms. These resources typically include:
- Driver board circuit diagrams.
- Sample code for initializing the display.
- Functions for drawing text, images, and shapes.
- Examples demonstrating full and partial refresh.
It is highly recommended to consult these official resources for detailed programming guidance specific to your chosen microcontroller.
7. Maintenance
E-Ink displays are generally low-maintenance. Follow these guidelines to ensure longevity:
- Handling: Handle the module carefully. Avoid applying excessive pressure or bending the display panel, as this can cause damage.
- Cleaning: Use a soft, dry, lint-free cloth to gently wipe the display surface if necessary. Do not use liquid cleaners or abrasive materials.
- Storage: Store the module in a dry, dust-free environment within its specified operating temperature range.
- Power Cycling: While E-Ink retains content without power, regular power cycling (e.g., once a day or week) can help maintain display health, especially if the same static image is displayed for very long periods.
8. Troubleshooting
If you encounter issues with your Waveshare 2.9-inch E-Ink Display Module, consider the following troubleshooting steps:
- Display is Blank or Erratic:
- Power Supply: Verify that the module is receiving a stable 3.3V or 5V power supply. Some microcontrollers may provide slightly lower voltage under load, which can affect E-Ink operation.
- Connections: Double-check all SPI, DC, RST, BUSY, VCC, and GND connections. Ensure they are secure and correctly wired according to the pinout.
- Reset Pin: Ensure the RST pin is correctly toggled during initialization as per the example code.
- Busy Pin: Confirm that your code correctly monitors the BUSY pin before sending new commands or data.
- Display Shows Blobs or Artifacts:
- Manufacturing Defect: If blobs or persistent artifacts are present from the first use and cannot be cleared with a full refresh, the display may have a manufacturing defect. Contact Waveshare support for assistance.
- Incomplete Refresh: Ensure your refresh cycles are complete. Sometimes, partial refreshes can leave ghosting if not implemented correctly or if the display is not fully cleared periodically.
- Slow Refresh Rate:
- E-Ink displays inherently have slower refresh rates compared to LCDs. A full refresh takes approximately 3 seconds, and a partial refresh takes about 0.6 seconds. This is normal behavior for the technology.
- Code Issues:
- Libraries: Ensure you are using the correct and up-to-date libraries for your specific module and microcontroller.
- Example Code: Test with the official Waveshare example code first to rule out custom code issues.
9. Warranty and Support
Waveshare products typically come with a standard manufacturer's warranty. For specific warranty terms and conditions, please refer to the official Waveshare website or your purchase documentation.
For technical support, detailed documentation, and additional resources, please visit the official Waveshare support portal. If you encounter any issues that cannot be resolved using the troubleshooting guide, contacting Waveshare customer support directly is recommended.
Waveshare Official Website: www.waveshare.com
