Issue with e-ink display contrast fading after refresh - GxEPD2, XiaoESP32-S3, GDEY075T7

[davidyangarduino]

I'm working with a 7.5" e-Paper display (GDEY075T7) connected to a XIAO ESP32 S3 using the GxEPD2 library. After refreshing the display, I'm experiencing contrast fade-out where the previously clear black image gradually lose clarity.

My code, with the help of Claude 3.7, downloads BMP images via WiFi and displays them on the e-ink screen. I use GxEPD2 Library to program the display. The text and drawing function works properly as intended.

Current implementation includes:

• GxEPD2_BW library with GDEY075T7 panel
• WiFi downloading of bitmap images
• Standard refresh cycle with display.refresh()
• Anti-ghosting attempt with clearScreen()

I’m trying various ways to debug the code, but I’d love to know if anyone here:

1. Has experience loading BMP images over Wi-Fi to an e-ink display and getting them to render properly without fadeout
2. Can help determine whether this is a hardware or software issue that’s causing the display to behave this way.

Thank you so much!

Below is a sequence of screenshots showing what happens when the image loads:

• The image briefly appears with proper contrast (less than a second)
• It immediately enters a refresh sequence
• Then the image fades out, with a horizontal line appearing across it

[silentobserver]

Your connection module has no RESE switch, and afaik a RESE value of 2.2 Ohms, which is ok for SSD controllers, but should be 0.47 Ohms for your panel.
This may be the reason for your issue.