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ILI9341 TFT Panel~

Display image

Models:

The "red" 240x320 TFT displays with an ILI9341 controller and XPT2046 touch controller are very common.

Make sure to select the touch version when ordering these screens online. The U2 touch chip needs to be populated on the board.

Pin Configuration~

Pin Function ESP32 Pin Config Name Display Pin
1 5V/3.3V power input 5V/3.3V VCC
2 Module Ground GND GND
3 Chip Select GPIO26 TFT_CS CS
4 LCD Reset line GPIO15 TFT_RST RESET
5 Data Command control GPIO5 TFT_DC DC
6 Data Input GPIO23 TFT_MOSI SDI(MOSI)
7 SPI Clock GPIO18 TFT_SCLK SCK
8 Backlight GPIO21 TFT_BCKL LED
9 Data Output (not used) GPIO19 or N/C TFT_MISO SDO(MISO)
10 Touch SPI Clock GPIO18 TFT_SCLK T_CLK
11 Touch Select GPIO17 TOUCH_CS T_CS
12 Touch Data Input GPIO23 TFT_MOSI T_DIN
13 Touch Data Output GPIO19 TFT_MISO T_DO
14 Touch Interrupt N/C T_IRQ

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

In some cases the pin 9 MISO of the LCD can prevent proper display initialization. This pin is not used by openHASP, so it can be left disconnected in case of issues.

LCD Configuration~

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

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lolin24 =
    -D ILI9341_DRIVER=1
    -D TFT_WIDTH=240
    -D TFT_HEIGHT=320
    -D TFT_ROTATION=0 ; Use default, see TFT_ROTATION values
    -D SPI_FREQUENCY=40000000
    -D SPI_TOUCH_FREQUENCY=2500000
    -D SPI_READ_FREQUENCY=20000000
    -D USER_SETUP_LOADED=1
    -D TOUCH_DRIVER=2046     ; XPT2046 Resistive SPI touch panel driver
    -D SUPPORT_TRANSACTIONS

HASP build_flags~

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

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build_flags =
    ${env.build_flags}
    ${esp32.build_flags}

;region -- TFT_eSPI build options ------------------------
    ${lcd.lolin24}
    ${esp32.vspi}        ; Use VSPI hardware SPI bus
    -D TFT_DC=5
    -D TFT_CS=26 
    -D TFT_RST=-1        ; RST
    -D TFT_BCKL=-1       ; None, configurable via web UI (e.g. 21)
    -D TOUCH_CS=17       ; (can also be 22 or 16)
;endregion