Error in LCD library

Libraries
1

I’m trying to run several different examples of using an ESP32 with an LCD IC2 display and keep getting this error

In file included from src/main.cpp:4:
.pio/libdeps/lilygo-t-display/LiquidCrystal/LiquidCrystal_I2C.h:122:17: note: candidate: 'virtual void LiquidCrystal_I2C::begin(uint8_t, uint8_t, uint8_t)'
    virtual void begin(uint8_t cols, uint8_t rows, uint8_t charsize = LCD_5x8DOTS);
                 ^~~~~
.pio/libdeps/lilygo-t-display/LiquidCrystal/LiquidCrystal_I2C.h:122:17: note:   candidate expects 3 arguments, 0 provided 
*** [.pio\build\lilygo-t-display\src\main.cpp.o] Error 1

I’ve tried including several different LiquidCrystal.h files but seem to get the same problem.

Any pointers would help

2

Do you really want to talk to an externally connected I2C LCD screen?

61YEYlAhMzL.AC_UF894,1000_QL80
61YEYlAhMzL.AC_UF894,1000_QL80894×725 70.8 KB

Or the on-board **1.14 inch ST7789V IPS LCD of the board?

grafik
grafik711×445 94.3 KB

3

Looks good but doesn’t solve my problem

4

Well you really didn’t answer my question.

In any case, if you really are wanting to talk to an external I2C LCD even though you have an on-board LCD (???) the lcd.begin() function takes as said above the number of columns and rows, so e.g. lcd.begin(16, 2); for 16x2 LCD.

You usually specify those paramters in the constructor though and just call the parameterless lcd.init().

See https://www.makerguides.com/character-i2c-lcd-arduino-tutorial/

#include "Wire.h" // Library for I2C communication
#include "LiquidCrystal_I2C.h" // Library for LCD

LiquidCrystal_I2C lcd = LiquidCrystal_I2C(0x27, 16, 2); // Change to (0x27,20,4) for 20x4 LCD.

void setup() {
  // Initiate the LCD:
  lcd.init();
  lcd.backlight();
}

void loop() {
  // Print 'Hello World!' on the first line of the LCD:
  lcd.setCursor(2, 0); // Set the cursor on the third column and first row.
  lcd.print("Hello World!"); // Print the string "Hello World!"
  lcd.setCursor(2, 1); //Set the cursor on the third column and the second row (counting starts at 0!).
  lcd.print("LCD tutorial");
}
5

Thanks, but the error is coming from the LCD header file (LIQUIDCRYSTAL_i2c.h) not my code.

Regards
Pete

6

Yes it comes from your code. Your src/main.cpp calls the library.

In file included from src/main.cpp:4: