Notes on ESP32 displays, tested on real boards
Fixes for the problems we run into, comparisons built from our board data, and projects you can open in the editor. Where a number matters, we measure it on hardware.
Which Cheap Yellow Display Do You Have? A Two-Minute Check
Boards sold as the ESP32-2432S028 come with an ILI9341, an inverted ILI9341 or an ST7789, with resistive or capacitive touch. How to tell which one is on your desk before you lose an evening to the wrong driver.
ProjectsHow to Add a Relay to a Cheap Yellow Display Without Running Out of GPIOs
Switching a relay from the ESP32-2432S028: which pin to use, why most 5 V relay modules need care on a 3.3 V board, what one relay costs you in sensors, and when to move to an MCP23017 expander instead.
3 min read
LVGLHow to Design an ESP32 Display UI That Doesn't Look Like a Default Demo
Why so many ESP32 and LVGL screens look the same, and the handful of changes that fix it: one font scale, a real colour palette, fewer widgets, grouping and contrast that survives a cheap panel. With notes on doing it in LCD Ultra Pro.
3 min read
Boards & hardwareSensors on the Cheap Yellow Display: BME280, DHT22, Soil Moisture and Light
Which pin each common sensor needs on the ESP32-2432S028, why the order you pick them in matters, and the light sensor that is already on the board. With wiring notes for BME280, DHT22, a capacitive soil probe and an LDR.
4 min read
LVGLShowing Live Sensor Data on an ESP32 Display: Labels, Gauges and Charts
Which LVGL widget fits which kind of value, how often to update each one, and how to wire sensor readings to labels, bars, arcs, meters and charts in LCD Ultra Pro without writing the update code.
3 min read
ProjectsBuild a Weather Station on the Cheap Yellow Display
A desk weather display on the ESP32-2432S028: live forecast from Open-Meteo with no API key, indoor temperature from a BME280 on the CN1 connector, built in LCD Ultra Pro and exported as an Arduino project.
3 min read
FixesCheap Yellow Display Touch Not Working? XPT2046 Fixes That Actually Help
No touch at all, taps landing in the wrong place, phantom presses, or touch that dies the moment you add an SD card. What causes each one on the ESP32-2432S028 and how to fix it.
3 min read
FixesCheap Yellow Display Won't Upload? Fixing "Failed to Connect" and Missing COM Ports
No port in the Arduino IDE, "Failed to connect to ESP32", "Wrong boot mode detected (0x13)" or a sketch that is too big. The usual causes on the ESP32-2432S028 and what to do about each.
3 min read
FixesWhy Is My ESP32 or Cheap Yellow Display Screen White? 8 Causes and Fixes
A white ESP32 or CYD display almost always means the backlight works and the display controller never got set up. The eight usual reasons, in the order worth checking them, from wrong pins to a missing PSRAM setting.
5 min read
Boards & hardwareGT911, CST816, FT6336, XPT2046: ESP32 Touch Controllers Compared
Which touch controllers show up on ESP32 display boards, how they differ, and the quirks that actually cause trouble: GT911 address selection, CST816 sleeping through an I2C scan, and XPT2046 calibration.
4 min read
Boards & hardwareWhich GPIO Pins Are Actually Free on the Cheap Yellow Display?
On the original ESP32-2432S028R only GPIO 22, 27 and 35 reach a header unused, and 35 is input-only. Where the other pins went, what each connector carries, and how to fit your sensors anyway.
4 min read
LVGLLVGL on the Cheap Yellow Display: A Setup That Works Without PSRAM
Getting LVGL running on the ESP32-2432S028: choosing between LVGL 8 and 9, where lv_conf.h goes, how big the draw buffers should be on a board with no PSRAM, and the display and touch glue that ties it together.
4 min read
Boards & hardwareSPI, QSPI, RGB and MIPI Displays on ESP32: What the Interface Means for Your Project
How an ESP32 talks to its screen decides how big the screen can be, how smooth it feels, how many pins you have left and whether you need PSRAM. A practical comparison based on the 101 boards in our catalog.
4 min read
Inside the editorSee Your UI on the Real Board Before You Compile: USB Live Explained
USB Live mirrors the LCD Ultra Pro canvas onto a real ESP32 display over USB while you edit, with no compiling. What it is good for, what it deliberately doesn't do, and how to set it up.
3 min read