Waveshare · ESP32-S3 · 2.1" · 480×480
Waveshare ESP32-S3 Touch LCD 2.1" round specifications
The ESP32-S3-Touch-LCD-2.1 is a round 2.1-inch display with 480×480 pixels — four times the pixel count of the popular 1.28-inch round boards — driven by an ST7701 over a 16-bit RGB interface. Touch comes from a CST820 capacitive controller on I2C.
Waveshare packs the 75 mm round board with extras: a PCF85063 real-time clock with backup battery header, a QMI8658 6-axis IMU, a buzzer, a lithium battery charger with power button, and a TCA9554 I/O expander. The ESP32-S3R8 provides 8 MB of PSRAM and 16 MB of flash for smooth full-screen graphics.
Two USB-C ports — native USB and a CH343P USB-to-UART — plus an IPEX connector for an external antenna make it a well-equipped base for a smart thermostat or a round control panel.
- Screen
- 2.1" · 480×480
- Chip
- ESP32-S3
- Memory
- 16 MB flash, 8 MB PSRAM
- Input
- capacitive touch
Key features
- Round 2.1-inch, 480×480, ST7701 over RGB
- Capacitive touch (CST820)
- ESP32-S3R8: 8 MB PSRAM, 16 MB flash
- PCF85063 RTC, QMI8658 IMU, buzzer
- LiPo charging with power button
- Two USB-C ports, TF slot, IPEX antenna option
Specifications
| Manufacturer | Waveshare |
|---|---|
| Screen size | 2.1" |
| Resolution | 480×480 px |
| Colour depth | 16-bit |
| Display controller | ST7701 (RGB Parallel + 3-wire SPI init) |
| Display interface | RGB565 Parallel (DPI) + SPI init sequence |
| Touch | CST820 (I2C) |
| Microcontroller | ESP32-S3 |
| Module | ESP32-S3R8 |
| CPU clock | 240 MHz |
| Internal SRAM | 512 KB |
| PSRAM | 8 MB |
| Flash | 16 MB |
| Wi-Fi | Yes |
| Bluetooth | Yes |
| Display type | TFT, round, RGB interface (RGB565 in practice) |
| Touch | Capacitive, CST820 (I2C), single touch |
| RTC | PCF85063 with backup battery header |
| IMU | QMI8658 6-axis |
| Audio | On-board buzzer |
| Battery | 3.7 V lithium via MX1.25, charge manager, power button |
| USB | USB-C native + USB-C CH343P USB-to-UART |
| Diameter | 75 mm |
| Development platforms (manufacturer) | Arduino IDE, ESP-IDF 5.3.1+ |
GPIO pinout
The GPIOs the board itself uses — display, touch and on-board peripherals — as published in the manufacturer’s documentation.
| GPIO | Function |
|---|---|
| GPIO 1 | LCD_MOSI (init SPI) |
| GPIO 2 | LCD_CLK (init SPI) |
| GPIO 3 | LCD_DATA12 (RGB) |
| GPIO 4 | BAT_ADC (battery voltage) |
| GPIO 5 | LCD_DATA0 (RGB) |
| GPIO 6 | Backlight (LCD_Backlight_PIN) |
| GPIO 7 | I2C_SCL (touch / RTC / IMU / IO expander) |
| GPIO 8 | LCD_DATA13 (RGB) |
| GPIO 9 | LCD_DATA10 (RGB) |
| GPIO 10 | LCD_DATA9 (RGB) |
| GPIO 11 | LCD_DATA8 (RGB) |
| GPIO 12 | LCD_DATA7 (RGB) |
| GPIO 13 | LCD_DATA6 (RGB) |
| GPIO 14 | LCD_DATA5 (RGB) |
| GPIO 15 | I2C_SDA (touch / RTC / IMU / IO expander) |
| GPIO 16 | TOUCH_INT (CST820) |
| GPIO 17 | LCD_DATA15 (RGB) |
| GPIO 18 | LCD_DATA14 (RGB) |
| GPIO 19 | USB D- (on the header, usable as GPIO only without native USB) |
| GPIO 20 | USB D+ (on the header, usable as GPIO only without native USB) |
| GPIO 21 | LCD_DATA4 (RGB) |
| GPIO 38 | LCD_HSYNC |
| GPIO 39 | LCD_VSYNC |
| GPIO 40 | LCD_DE |
| GPIO 41 | LCD_PCLK |
| GPIO 42 | SD_MISO (microSD; MOSI / SCK share GPIO 1 / 2 with the LCD init bus, CS on EXIO4) |
| GPIO 45 | LCD_DATA1 (RGB) |
| GPIO 46 | LCD_DATA11 (RGB) |
| GPIO 47 | LCD_DATA3 (RGB) |
| GPIO 48 | LCD_DATA2 (RGB) |
Source: www.waveshare.com. Always check against your board revision before wiring.
Free GPIOs and connectors
These GPIOs are not used by the display, touch or on-board peripherals, so you can wire your own sensors, buttons or relays to them.
| Pin | Capabilities | Note |
|---|---|---|
| GPIO 0 | GPIO, BOOT | BOOT button — also on the 12-pin header |
| GPIO 43/TX | GPIO, UART_TX | UART0 TX — on the UART connector and the 12-pin header (only when the USB-to-UART Type-C port is not connected) |
| GPIO 44/RX | GPIO, UART_RX | UART0 RX — on the UART connector and the 12-pin header (only when the USB-to-UART Type-C port is not connected) |
- 12-pin header — GPIO 0, 43, 44 (IO0, TX, RX)
The header also carries USB D- / D+ (GPIO 19 / 20) and the I2C bus (GPIO 15 / 7) — GPIO 0 is the BOOT button (keep it high at power-up)
- UART connector — GPIO 43, 44 (TX, RX)
Only when the USB-to-UART Type-C port is not connected
- I2C connector — GPIO 15, 7 (SDA, SCL)
Same I2C bus as the touch controller, the IO expander, the RTC and the IMU (addresses 0x15/0x5D, 0x20, 0x51, 0x6B, 0x7E taken)
Good to know before you start
- The I2C bus is busy: addresses 0x15, 0x20, 0x51, 0x6B and 0x7E are taken by touch, expander, RTC and IMU — choose sensors with other addresses.
- The TCA9554 expander is fully used internally and not exposed.
- UART0 on the header only works when the USB-to-UART port is not connected.
- Free GPIOs are scarce: plan expansion over I2C.
What it is good for
- •Smart thermostats with a clock
- •Round smart home controllers
- •Instrument-style gauges at high resolution
- •Alarm clocks using the RTC and buzzer
LVGL support in LCD Ultra Pro
| Driver status | Matched to the manufacturer’s official demo, compile-tested |
|---|---|
| Arduino export | Complete LVGL 8.4 project with the display driver |
| USB Live preview | No |
| Orientations | 0° |
| Brightness control | Hardware backlight dimming |
Pick this board in the editor and the canvas matches its exact resolution and shape. Build the interface with widgets, add events without code, try it in Live Preview, then export it as a ready-to-compile Arduino project. See the documentation for the workflow.
Frequently asked questions
What resolution is the Waveshare 2.1-inch round display?
480×480 pixels, driven by an ST7701 over a 16-bit RGB interface.
Does it have a real-time clock?
Yes, a PCF85063 RTC with a header for a backup battery.
Which I2C addresses are already used?
0x15, 0x20, 0x51, 0x6B and 0x7E (touch, I/O expander, RTC and IMU).
Does it support multi-touch?
No. The CST820 controller reports a single touch point.
Sources
Specifications cross-checked against the manufacturer’s documentation (last checked 2026-10-27):
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