Cheap Yellow Display simulator, an ESP32 with a touch screen
The Cheap Yellow Display, Sunton’s ESP32-2432S028R, is a classic ESP32, of which one Xtensa LX6 core runs here, behind a 2.8 inch 240x320 ILI9341 screen with an XPT2046 touch film. Both are wired inside the board as on the real one, so TFT_eSPI needs no setup file and you touch the screen by pressing it. WiFi joins a simulated network.
- 7peripheral areas modeled
- 2projects ready to run
- Real timeon your own machine
What is modeled
Taken from the board's own contract document and put in plain words, with what is missing beside it.
Modeled
- Core
- One Xtensa LX6 core, the DevKit V1 model whole
- The screen
- The ILI9341 part on HSPI: MOSI 13, MISO 12, SCK 14, CS 15, DC 2, backlight on GPIO 21
- The touch film
- The XPT2046 on its own lines: CLK 25, DIN 32, DO 39, CS 33, IRQ 36. Press the screen to touch it
- TFT_eSPI
- The board’s User_Setup.h built in, so a sketch that names no pins draws on the screen
- The RGB LED
- GPIO 4, 16 and 17, each color lit when its pin is LOW
- The connectors
- P1, P3 and CN1, by the names Wokwi’s drawing gives them
- WiFi, simulated
- WiFi.h over a network written in software: no radio, no 802.11, no real internet
Not modeled
- The light sensor on GPIO 34, the speaker amplifier on GPIO 26 and its connector, and the microSD slot on VSPI.
- CN1’s second IO22: here IO22 is only on P3, as in Wokwi’s drawing.
- Reading the panel back over MISO: it gives black.
- The second core, ADC2, Bluetooth and a real radio.
Open one and press Run
Each of these opens in the editor exactly as it is drawn here.
Every built-in project on the Cheap Yellow Display
Each has its own page with the circuit running, the code and a parts list.
Tutorials that use this board
Each one ends in a running circuit, on this same board.
Questions
Is it free?
Yes. Every board and every part is on the free plan, with no account needed.
Do I need a User_Setup.h?
Not here. If your sketch names no TFT pins, TFT_eSPI gets the board’s setup: ILI9341_2_DRIVER, MISO 12, MOSI 13, SCLK 14, CS 15, DC 2, RST -1, backlight 21. On a real board you install that setup in the TFT_eSPI library folder, as the tutorials say.
How do I touch the screen?
Press on it while the circuit runs, and drag to move your finger. The sketch reads the XPT2046 with XPT2046_Touchscreen on its own SPIClass(VSPI), on CLK 25, MISO 39, MOSI 32 and CS 33, with IRQ on 36.
Why is the board drawn upright?
So it fits beside a breadboard. The real board lies landscape. Rotate the part to lay it the same way; setRotation(1) in the sketch turns the picture to landscape too.
The other boards
Every one of these runs today, and every one is free.
A RISC-V chip at 160 MHz, on the real memory map.
The classic Arduino, with an ATmega328P running at 16 MHz.
The Uno’s chip on a small board that fits a breadboard.
The big Arduino, with 54 digital pins and four serial ports.
An Uno-shaped board whose chip does its own USB serial.
A second RISC-V board, with 31 pins and simulated WiFi.
The classic ESP32 at 240 MHz, with simulated WiFi.
The ESP32-S3 at 240 MHz, with USB serial and an RGB LED.
Try it on your own firmware
What you build here runs on the board on your desk, unchanged. Nothing to install and no account needed.