gdey029T94 176x264 4 gray

• Size: 176 * 264, inches: 2.9
• Buffer size: 4736 bytes (2x additional buffers in 4 gray mode)
• Controller: SSD1680 (Solomon)
• Status: Working 4 grays mode is working
• Partial update: Works

Buy this 2.9" epaper here

Tech specs

IC Driver SSD1680 (pdf)

There is also a model with front light, model nr. gdey029T94-FL. Tried it for this model with 7.4 Volts battery and a resistance of 430 Ohm (I always try LEDs with a resistance). Do not feed this from any MCU pin directly because they are white LEDs in serie so 3.3 or 5V won't make it emit light and also usually there are 3 or 4 leds which consume more than what an ESP32 can deliver so you burn the GPIO. Use always some transistor or FET and switch it from an IO so you can also have PWM.

Implementation example

Without touch:

#include "goodisplay/gdey029T94.h"
EpdSpi io;
Gdey029T94 display(io);

void app_main() {
  display.init();
  display.setMonoMode(true);       // Use monochorome mode
  display.print("Hello black");
  display.update();

  display.setMonoMode(false);      // Use 4 gray mode (Which uses 2 different buffers)
  display.setCursor(10,20);        // Move text cursor to x:10 y:20
  display.setTextColor(EPD_LGRAY); // Tint color to Light gray
  display.print("Hello GRAY");
  display.update();

  // Now if you want to switch to mono mode again, that layer has still the old buffer, so doing this:
  display.setMonoMode(true);       // Switch to mono again which uses mono buffer that is still there
  display.update();                // Should print again "Hello black"
}