Waveshare RPi LCD (Rev C)

Models~

The Waveshare RPi LCD (Rev C) display comes in 3.5" and 4.0" sizes:

Model	3.5inch (Rev C)	4.0inch (Rev C)
SKU	15811	16099
Resolution	480x320	480x320
TFT controller	ILI9486	ST7796
Interface	SPI	SPI
Touchscreen	Resistive	Resistive
Touch controller	XPT2046	XPT2046
Screen dimming	yes	yes
	Buy Amazon US Amazon UK Amazon DE Amazon FR Amazon ES Amazon NL AliExpress Waveshare.com	Buy AliExpress Waveshare.com

Backlight Control~

By default the display is always on. To enable backlight dimming, you can connect the pads marked by the red arrow using a 0R resistor or a direct solder connection:

Attention (*)

The WaveShare 3.5" RPi LCD Revision C (SKU 15811) and WaveShare 4.0" RPi LCD Revision C (SKU 16099) have the solder jumper on the back to enable PWM backlight dimming. Most revisions of this board do not have this feature!

Development Boards~

ESP32 One~

The Waveshare ESP32 One development board has the same form factor as the Raspberry Pi Zero, inluding a 40 pin GPIO header. The ESP32 One is plug-and-play compatible with the Waveshare RPi LCD (Rev C) 3.5" and 4".

This board has 4 MB flash and 8 MB PSRAM.

Schematics

Gallery~

Pin Configuration~

LCD Pin	Function	ESP32 Pin	Config Name	Display Pin
1	Module Power 3.3V	3.3V		3.3V
2	Module Power 5v	5V		5V
3	Not connected			NC
4				5V
5-10	Not connected			NC
11	Touch Interrupt	NC		TP_IRQ
12 (*)	LED Backlight PWM	GPIO26	TFT_BCKL	LCD_LED
13	Not connected			NC
14	Module Ground	GND		GND
15-16	Not connected			NC
17	Module Power	3.3V		3.3V
18	Data Command control pin	GPIO4	TFT_DC	LCD_RS
19	SPI Master Out Slave In	GPIO13	TFT_MOSI	LCD/SI/TP_SI
20	Not connected			NC
21	Touch Panel Slave Out	GPIO12	TFT_MISO	TP_SO
22	LCD Reset pin	GPIO32	TFT_RST	RST
23	SPI Clock	GPIO14	TFT_SCLK	LCD_SCK/TP_SCK
24	Chip select control pin	GPIO5	TFT_CS	LCD_CS
25	Module Ground	GND		GND
26	Touch Chip Select	GPIO22	TOUCH_CS	TP_CS

SPI MISO, MOSI and SCLK are shared between the touch controller and the LCD controller.

You can also use jumper wires to connect the display to any ESP32 development board:

6 GPIOs are required to drive the SPI display. One additional GPIO is needed for the XPT2046 touch sensor and one extra GPIO for backlight dimming. Including the VCC and GND pins, a total of 13 connections need to be made to the MCU.

LCD Configuration~

The lcd_config.ini file specifies the different properties of the display, except for the actual pin configuration:

raspberrypi =
    -D RPI_DISPLAY_TYPE=1
    -D ST7796_DRIVER=1
    -D TFT_WIDTH=320
    -D TFT_HEIGHT=480
    -D TFT_ROTATION=0 ; 0=0, 1=90, 2=180 or 3=270 degree
    -D SPI_FREQUENCY=80000000
    -D SPI_TOUCH_FREQUENCY=2500000
    -D USER_SETUP_LOADED=1
    -D TOUCH_DRIVER=2046 ; XPT2046 Resistive touch panel driver
    -D SUPPORT_TRANSACTIONS

HASP build_flags~

Specify the LCD Configuration to use and define the GPIOs in the environment build flags:

build_flags =
    ${env.build_flags}
    ${esp32.build_flags}
    -DBOARD_HAS_PSRAM               ; uses 78kB

; -- TFT_eSPI build options ------------------------
    ${lcd.raspberrypi}
    ${esp32.hspi}        ; Use HSPI hardware SPI bus
    -D TFT_CS=5
    -D TFT_DC=4
    -D TFT_RST=32
    -D TFT_BCKL=26       ; Default, configurable via web UI
    -D TOUCH_CS=22
    -D SD_CS=15          ; Currently not supported

Last update: 2023-12-09