lcd_1602.c

基于AVR的数字频率计

#include "def.h"
#include "LCD_1602.h"
unsigned char uctech[] = {"Happy every day"};
unsigned char net[] = {"<LHJ>"};

void TEST_LCD(void)
{
 delay_nms(400); //启动等待，等LCD讲入工作状态
 LCDInit(); //LCM初始化
 delay_nms(5); //延时片刻(可不要)

 DisplayListChar(0, 0, uctech);
 DisplayListChar(5, 5, net);

 while(1);
}

WriteDataTo595(unsigned char WDLCD)
{
	unsigned char i;
	CLR_74LS595_SHIFT;
	for(i=0;i<8;i++)
		{
			CLR_74LS595_CLK;
			if(WDLCD&0x01)
				SET_74LS595_DI;
			else
				CLR_74LS595_DI;
			WDLCD>>1;
			SET_74LS595_CLK;	
		}
	SET_74LS595_SHIFT;	
}

//写数据
void WriteDataLCD(unsigned char WDLCD)
{
 WriteDataTo595(WDLCD);
 SET_LCD_RS;
 CLR_LCD_RW;
 CLR_LCD_E; //若晶振速度太高可以在这后加小的延时
 _delay_loop_2(1);
 SET_LCD_E;
}

//写指令
void WriteCommandLCD(unsigned char WCLCD) //BuysC为0时忽略忙检测
{
 WriteDataTo595(WCLCD);
 CLR_LCD_RS;
 CLR_LCD_RW; 
 CLR_LCD_E;
 _delay_loop_2(1);
 SET_LCD_E; 
}


void LCDInit(void) //LCM初始化
{
 WriteDataTo595(0);
 WriteCommandLCD(0x38,0); //三次显示模式设置，不检测忙信号
 delay_nms(5);
 WriteCommandLCD(0x38,0);
 delay_nms(5);
 WriteCommandLCD(0x38,0);
 delay_nms(5);

 WriteCommandLCD(0x38,1); //显示模式设置,开始要求每次检测忙信号
 delay_nms(5);
 WriteCommandLCD(0x08,1); //关闭显示
 delay_nms(5);
 WriteCommandLCD(0x01,1); //显示清屏
 delay_nms(5);
 WriteCommandLCD(0x06,1); // 显示光标移动设置
 delay_nms(5);
 WriteCommandLCD(0x0C,1); // 显示开及光标设置
 delay_nms(5);
}

//按指定位置显示一个字符
void DisplayOneChar(unsigned char X, unsigned char Y, unsigned char DData)
{
 Y &= 0x1;
 X &= 0xF; //限制X不能大于15，Y不能大于1
 if (Y) X |= 0x40; //当要显示第二行时地址码+0x40;
 X |= 0x80; // 算出指令码
 WriteCommandLCD(X, 0); //这里不检测忙信号，发送地址码
 WriteDataLCD(DData);
}

//按指定位置显示一串字符
void DisplayListChar(unsigned char X, unsigned char Y, unsigned char  *DData)
{
 unsigned char ListLength;

  ListLength = 0;
 Y &= 0x1;
 X &= 0xF; //限制X不能大于15，Y不能大于1
 while (DData[ListLength]>=0x20) //若到达字串尾则退出
  {
   if (X <= 0xF) //X坐标应小于0xF
    {
     DisplayOneChar(X, Y, DData[ListLength]); //显示单个字符
     ListLength++;
     X++;
    }
  }
}