avr_piano/lcd.c

#include <avr/io.h>

#define F_CPU	16000000UL
#include <util/delay.h>

// Define LCD control pin connections
#define LCD_RS_PIN	PB0
#define LCD_RW_PIN	PB1
#define LCD_E_PIN	PB2
#define LCD_RS_PORT	PORTB
#define LCD_RW_PORT	PORTB
#define LCD_E_PORT	PORTB
// Define LCD data pin connections
#define LCD_DATA_PORT	PORTD
#define LCD_DATA_DDR	DDRD

// Function prototypes
void LCD_init();
void LCD_command(uint8_t cmd);
void LCD_write(uint8_t data);
void LCD_send(char* str);

int
main()
{
	// Set control pins as outputs
	DDRB |= (1 << LCD_RS_PIN) | (1 << LCD_RW_PIN) | (1 << LCD_E_PIN);
	// Set data pins as outputs
	LCD_DATA_DDR = 0xFF;

	// Initialize LCD
	LCD_init();

	// Display "Hello, World!"
	LCD_send("Hello, World!");

	for (;;) {
		// Your main code here
	}

	return 0;
}

// Initialize LCD
void
LCD_init()
{
	_delay_ms(15);		// Delay for power-on
	LCD_command(0x38);	// Function Set: 8-bit data, 2-line display, 5x8 font
	LCD_command(0x0C);	// Display ON, Cursor OFF, Blink OFF
	LCD_command(0x01);	// Clear display
	_delay_ms(2);		// Delay for Clear Display command
	LCD_command(0x06);	// Entry Mode Set: Increment cursor, No display shift
}

// Send command to LCD
void
LCD_command(uint8_t cmd)
{
	LCD_RS_PORT &= ~(1 << LCD_RS_PIN);	// Set RS low for command mode
	LCD_RW_PORT &= ~(1 << LCD_RW_PIN);	// Set RW low for write mode
	LCD_DATA_PORT = cmd;			// Send command to data port
	LCD_E_PORT |= (1 << LCD_E_PIN);		// Enable LCD
	_delay_us(1);				// Short delay
	LCD_E_PORT &= ~(1 << LCD_E_PIN);	// Disable LCD
	_delay_us(100);				// Delay for command execution
}

// Write data to LCD
void
LCD_write(uint8_t data)
{
	LCD_RS_PORT |= (1 << LCD_RS_PIN);	// Set RS high for data mode
	LCD_RW_PORT &= ~(1 << LCD_RW_PIN);	// Set RW low for write mode
	LCD_DATA_PORT = data;			// Send data to data port
	LCD_E_PORT |= (1 << LCD_E_PIN);		// Enable LCD
	_delay_us(1);				// Short delay
	LCD_E_PORT &= ~(1 << LCD_E_PIN);	// Disable LCD
	_delay_us(100);				// Delay for data execution
}

// Send string to LCD
void
LCD_send(char *str)
{
	while (*str)
		LCD_write(*str++);
}