lcd1602.c

用AVR单片机做的一些程序,包括跑马灯显示,PWM产生,ADC转换等

/*
	LCD1602液晶屏驱动模块
	1、可直接嵌入到项目中使用
	2、晶振频率：1M
	3、如晶振提高低层驱动延时要作相应修改

	AVR_AFA
	www.iccavr.com
	程序编写过程中参照了peak的4线显示程序
	peak：AVR论坛技术版版主
*/

#include <iom128v.h>

#define RS_CLR	PORTC &= ~(1 << PC2)
#define RS_SET	PORTC |= (1 << PC2)

#define RW_CLR	PORTC &= ~(1 << PC3)
#define RW_SET	PORTC |= (1 << PC3)

#define EN_CLR	PORTC &= ~(1 << PC4)
#define EN_SET	PORTC |= (1 << PC4)

/*延时函数*/
void delay_us(unsigned int n) {

	if (n == 0) {
		return ;
		}
	while (--n);
}

/*延时函数*/
void delay_ms(unsigned char i) {

	unsigned char a, b;
	for (a = 1; a < i; a++) {
		for (b = 1; b; b++) {
			;
			}
		}
}

/*显示屏命令写入函数*/
void LCD_write_com(unsigned char com) {
	
	RS_CLR;
	RW_CLR;
	EN_SET;
	PORTA = com;
	delay_us(5);
	EN_CLR;
}

/*显示屏命令写入函数*/
void LCD_write_data(unsigned char data) {

	RS_SET;
	RW_CLR;
	EN_SET;
	PORTA = data;
	delay_us(5);
	EN_CLR;
}

/*显示屏清空显示*/
void LCD_clear(void) {

	LCD_write_com(0x01);
	delay_ms(5);
}

/*显示屏字符串写入函数*/
void LCD_write_str(unsigned char x,unsigned char y,unsigned char *s) {
	
    if (y == 0) {
    	LCD_write_com(0x80 + x);
    	}
    else {
    	LCD_write_com(0xC0 + x);
    	}
    
    while (*s) {
    	LCD_write_data( *s);
    	s ++;
    	}
}

/*显示屏单字符写入函数*/
void LCD_write_char(unsigned char x,unsigned char y,unsigned char data) {
	
    if (y == 0) {
    	LCD_write_com(0x80 + x);
    	}
    else {
    	LCD_write_com(0xC0 + x);
    	}
    
    LCD_write_data( data);  
}

/*显示屏初始化函数*/
void LCD_init(void) {
	
	DDRA = 0xFF;						/*I/O口方向设置*/
	DDRC = 0xFF;
	LCD_write_com(0x38);				/*显示模式设置*/
	delay_ms(5);
	LCD_write_com(0x38);
	delay_ms(5);
	LCD_write_com(0x38);
	delay_ms(5);
	LCD_write_com(0x38);
	
	LCD_write_com(0x08);				/*显示关闭*/
	LCD_write_com(0x01);				/*显示清屏*/
	LCD_write_com(0x06);				/*显示光标移动设置*/
	delay_ms(5);
	LCD_write_com(0x0C);				/*显示开及光标设置*/
}