我感觉我这个最简单。
#include <avr/io.h>
#include <util/delay_basic.h>
#include <avr/eeprom.h>
#include <avr/wdt.h>
#define freq 11.0592
#define uint unsigned int
#define uchar unsigned char
#define lcd_en_port portd
#define lcd_rw_port portd
#define lcd_rs_port portd
#define lcd_data_port portc
#define lcd_data_ddr ddrc
#define lcd_data_pin pinc
#define lcd_en pd7 //portd7 out
#define lcd_rs pd5 //portd5 out
#define lcd_data 0x0f //portc 0/1/2/3 out
#define lcd_rw pd6 //portd 6 out
/*--------------------------------------------------------------------------------------------------
public function prototypes
--------------------------------------------------------------------------------------------------*/
void lcd_init (void); //初始化
void delay_nus (unsigned int n);
void delay_nms (unsigned int n);
void wrc (unsigned char x); //设定地址
void wrd (unsigned char x);//写字符
void dis (unsigned char x);//写100以内的两位数
void lcd_init(void) //液晶初始化
{
delay_nms(15);
ddrc |= lcd_data; // 数据为输出
ddrd |= (1<<lcd_rs); //置位rs.en
ddrd |= (1<<lcd_en);
ddrd |= (1<<lcd_rw);
lcd_rw_port &= ~(1<<lcd_rw);
wrc(0x28); //4位显示
wrc(0x0c); //显示开
wrc(0x01); //清屏
delay_nms(60); //>40us
}
void wrd(uchar x)
{
uchar i;
lcd_rs_port |= (1<<lcd_rs); //rs=1
i = x>>4;
lcd_data_port &= 0xf0;
lcd_data_port |= i & 0x0f; //写高四位
lcd_en_write();
i = x;
lcd_data_port &= 0xf0;
lcd_data_port |= i & 0x0f; //写低四位
lcd_en_write();
delay_nus(50); //>40us
}
void wrc(uchar x)
{
uchar i;
lcd_rs_port &= ~(1<<lcd_rs); //rs=0
i = x>>4;
lcd_data_port &= 0xf0;
lcd_data_port |= i & 0x0f; //写高四位
lcd_en_write();
i = x;
lcd_data_port &= 0xf0;
lcd_data_port |= i & 0x0f; //写低四位
lcd_en_write();
delay_nus(50); //>40us
}
void lcd_en_write(void) //液晶使能
{
lcd_en_port |= (1<<lcd_en);
delay_nus(1);
lcd_en_port &= ~(1<<lcd_en);
delay_nus(1); //这里1us足够了
}
void dis(uchar x)
{
uchar i,j;
i=(x/10)|0x30;
wrd(i);
j=(x%10)|0x30;
wrd(j);
}
void delay_nms(unsigned int ms)
{
unsigned int i;
for(i=0;i<ms;i++ )
{
_delay_loop_2(250*freq); //16-bit count, 4 cycles/loop
}
}
void delay_nus(unsigned int us)
{
unsigned int i;
for(i=0;i<us;i++ )
{
_delay_loop_2(freq/4);
}
}
int main(void)
{
uchar u=3456;
delay_nms(1000);
lcd_init();
//以下在液晶上第一行写字符
wrc(0x80);
wrd('.');wrd('.');wrd('.');wrd('.');wrd('.');wrd('.');wrd('.');wrd('.');
wrd('.');wrd('.');wrd('.');wrd('.');wrd('.');wrd('.');wrd('.');wrd('.');
//以下在第二行显示3456
wrc(0xc0);
dis(u/100);dis(u%100);
while(1);
}
