lcd.h File Reference

Header file for I2C 20x4 LCD control functions. More...

#include "stm32f4xx_hal.h"

Go to the source code of this file.

Macros
#define	LCD_I2C_ADDR   (0x27 << 1)
	Adjust to match your LCD I2C address (typically 0x27 or 0x3F)

Functions
void	lcd_init (void)
	Initializes the LCD in 4-bit I2C mode.
void	lcd_clear (void)
	Clears the LCD display.
void	lcd_set_cursor (uint8_t row, uint8_t col)
	Sets the LCD cursor to a specific row and column.
void	lcd_print (char *str)
	Prints a null-terminated string to the LCD.
void	lcd_send_command (uint8_t cmd)
	Sends a command byte to the LCD.
void	lcd_send_data (uint8_t data)
	Sends a data byte (character) to the LCD.
void	lcd_force_backlight_on (void)
	Forces the LCD backlight to remain on.

Variables
I2C_HandleTypeDef	hi2c1
	External handle to use your I2C peripheral.

Detailed Description

Header file for I2C 20x4 LCD control functions.

Author

Andrew Carr and Kai De La Cruz

Created on: May 22, 2025

Function Documentation

lcd_force_backlight_on()

void lcd_force_backlight_on

(

void

)

Forces the LCD backlight to remain on.

Forces the LCD backlight to remain on.

lcd_init()

void lcd_init

(

void

)

Initializes the LCD in 4-bit I2C mode.

Initializes the LCD in 4-bit I2C mode.

lcd_print()

void lcd_print

(

char *

str

)

Prints a null-terminated string to the LCD.

Parameters

str	Pointer to the string to print

Prints a null-terminated string to the LCD.

Parameters

str	Null-terminated character string

lcd_send_command()

void lcd_send_command

(

uint8_t

cmd

)

Sends a command byte to the LCD.

Parameters

cmd	Command to send
cmd	Command byte

lcd_send_data()

void lcd_send_data

(

uint8_t

data

)

Sends a data byte (character) to the LCD.

Parameters

data	Character to display
data	Data byte

lcd_set_cursor()

void lcd_set_cursor	(	uint8_t	row,
		uint8_t	col )

Sets the LCD cursor to a specific row and column.

Parameters

row	Row index (0–3)
col	Column index (0–19)

Sets the LCD cursor to a specific row and column.

Parameters

row	Row index (0–3)
col	Column index (0–19)