This is the accompanying repository for my article "Create a digital clock in a Domino style on an ESP32 Cheap Yellow Display ("CYD")" available here: https://medium.com/@androidcrypto/create-a-colorful-digital-clock-on-an-esp32-cheap-yellow-display-cyd-641db4642e47
For short - what is a "Cheap Yellow Display" ? This device was introduced some years ago and allowed for very fast development of projects where an ESP32, a TFT (optional Touch surface), an SD Card Reader and an RGB LED is included. The first version was equipped with a 2.8 inch large TFT display with ILI9341 driver chip and XPT2046 resistive Touch driver chip. Newer versions are sold with a ST7789 display driver chip. Nowadays, the device is available with different display sizes (1.28 up to 7 inches) and driver chips, but I'm focusing on the 2.8 inch variants. The display has a size of 320 x 240 pixels in Landscape orientation. Most of the devices are driven by an ESP32 WROOM microcontroller, but I saw some others with an ESP32-S3 chip.
I'm using the Domino style images provided by judge2005 in the GitHub repository https://github.com/judge2005/EleksTubeIPS. You will find the originals in the path "more_faces | dom2". The original images are BMP encoded images with a size of 135 x 240 pixels, but this is far to much for our display, as I want to display the current time and date with 6 digits each. The second issue would be: how do I load the images into the sketch (SD-Card, LittleFS). I decided to use the "inline" style by converting the files in C-style header files.
For both the image size reducing and converting I used an internet service: https://mischianti.org/rgb-image-to-byte-array-converter-for-arduino-tft-displays/
Simply open each of the ten digit BMP files, set the new image size (here 50 x 88 pixels), convert the file and download it as *h file.
The are the default settings I used:
Settings (default):
Code format Hex 0x00
Palette mod 16bit RRRRRGGGGGGBBBBB (2byte/pixel)
Resize: use both parameters to match exact size, e.g. 50 x 88
Multi line yes
Endianness Little Endian
static yes
const yes
Data type uint16_t
PROGMEM yes
TFT_eSPI Version: 2.4.3 *1) (https://github.com/Bodmer/TFT_eSPI)
*1) In case you encounter any problems with the TFT_eSPI library you should consider to use my forked TFT_eSPI library that solved some problems, see link below
Forked TFT_eSPI library by AndroidCrypto: https://github.com/AndroidCrypto/TFT_eSPI
Please don't forget to copy the files "Setup801_ESP32_CYD_ILI9341_240x320.h" and "Setup805_ESP32_CYD_ST7789_240x320.h" in the "User_Setups" folder of the TFT_eSPI library and edit the "User_Setup_Select.h" to include the set up, depending on your CYD board type (ILI9341 or ST7789).
If you own an older version (one Micro-USB port) your display is driven by an ILI9341 driver chip, newer boards (one Micro-USB and one USB-C port) are using an ST7789 driver chip. Both of them should use a resistive touch controller of type XPT2046.
ILI9341: Setup801_ESP32_CYD_ILI9341_240x320.h
ST7789: Setup805_ESP32_CYD_ST7789_240x320.h
Arduino IDE Version 2.3.6 (Windows)
arduino-esp32 boards Version 3.2.0 (https://github.com/espressif/arduino-esp32)