lcd1602.c

Keil C 写的51单片机LCD1602的驱动程序

#include<reg51.h>
#include"inc/define.h"
#include"inc/lcd1602.h"

#define BUSY 0x80 		//用于检测LCD状态字中的Busy标识

u8 BusyCheck()	//忙检测  LCD正操作忙则返回1；不忙则返回0
{
	u8 flag;

	LCD_Data = 0xFF; 
	LCD_RS = 0;
	LCD_RW = 1;
	LCD_E = 1;
	flag = LCD_Data & BUSY;
	LCD_E = 0;

	return flag;
}
void BusyWait()	//忙等待  一直等到LCD不忙时再返回
{
	while(1 == BusyCheck())
		;
}

void WriteCMD(u8 CData) 
{
	BusyWait();
	LCD_Data = CData;
	LCD_RS = 0;
	LCD_RW = 0; 
	LCD_E = 1;	
	LCD_E = 0; 
}

void WriteData(u8 DData)
{
	BusyWait();
	LCD_Data = DData;
	LCD_RS = 1;
	LCD_RW = 0;
	LCD_E = 1;		 
	LCD_E = 0;		 
}

u8 ReadData()
{
	u8 DData;
	LCD_RS = 1; 
	LCD_RW = 1;
	LCD_E = 1;
	DData=LCD_Data;
	LCD_E = 0;

	return DData;
}

/**********在指定位置显示一个字符*************/
void DisplayChar(u8 x,u8 y,uchar DData)
{
	x &= 0xF; 			
	y &= 0x1;			//限制x不能大于15，y不能大于1
	if (1 == y) 
		x |= 0x40;   	//当要显示第二行时地址码 0x40;
	x |= 0x80; 			//算出指令码
	WriteCMD(x);		//这里不检测忙信号，发送地址码
	WriteData(DData);
}

/*********按指定位置显示一串字符**************/
void DisplayStr(u8 x,u8 y,uchar *DData)
{
	u8 char_posi = 0;
	x &= 0xF;
	y &= 0x1; 			//限制x不能大于15，y不能大于1
	while ((DData[char_posi] != '\0') && (x <= 0x0F)) //若到达字串尾则退出并且位置不在末尾
	{
		DisplayChar(x,y,DData[char_posi]);  //显示单个字符
	    char_posi++;
	    x++;
	}
}