使用1602液晶显示的实验例子

SMC1602A(16*2)模拟口线接线方式
连接线图:

|LCM-----51 　| LCM-----51　　|　LCM------51 |
|
|DB0-----P1.0 | DB4-----P1.4 | RW-------P2.0 |
|DB1-----P1.1 | DB5-----P1.5 | RS-------P2.1 |
|DB2-----P1.2 | DB6-----P1.6 | E--------P2.2 |
|DB3-----P1.3 | DB7-----P1.7 | VLCD接1K电阻到GND|

[注:AT89S51使用12M晶振]

#define LCM_RW P2_0 //定义引脚
#define LCM_RS P2_1
#define LCM_E P2_2
#define LCM_Data P1
#define Busy 0x80 //用于检测LCM状态字中的Busy标识

#include <at89x51.h>

void WriteDataLCM(unsigned char WDLCM);
void WriteCommandLCM(unsigned char WCLCM,BuysC);
unsigned char ReadDataLCM(void);
unsigned char ReadStatusLCM(void);
void LCMInit(void);
void DisplayOneChar(unsigned char X, unsigned char Y, unsigned char DData);
void DisplayListChar(unsigned char X, unsigned char Y, unsigned char code *DData);
void Delay5Ms(void);
void Delay400Ms(void);

unsigned char code cdle_net[] = {"www.cdle.net"};
unsigned char code email[] = {"pnzwzw@cdle.net"};

void main(void)
{
Delay400Ms(); //启动等待，等LCM讲入工作状态
LCMInit(); //LCM初始化
Delay5Ms(); //延时片刻(可不要)

DisplayListChar(0, 0, cdle_net);
DisplayListChar(0, 1, email);
ReadDataLCM();//测试用句无意义
while(1);
}

//写数据
void WriteDataLCM(unsigned char WDLCM)
{
ReadStatusLCM(); //检测忙
LCM_Data = WDLCM;
LCM_RS = 1;
LCM_RW = 0;
LCM_E = 0; //若晶振速度太高可以在这后加小的延时
LCM_E = 0; //延时
LCM_E = 1;
}

//写指令
void WriteCommandLCM(unsigned char WCLCM,BuysC) //BuysC为0时忽略忙检测
{
if (BuysC) ReadStatusLCM(); //根据需要检测忙
LCM_Data = WCLCM;
LCM_RS = 0;
LCM_RW = 0;
LCM_E = 0;
LCM_E = 0;
LCM_E = 1;
}

//读数据
unsigned char ReadDataLCM(void)
{
LCM_RS = 1;
LCM_RW = 1;
LCM_E = 0;
LCM_E = 0;
LCM_E = 1;
return(LCM_Data);
}