lcd.c

c8051f020+ad9852＋12864＋键盘（频率合成）贝一特电子

#include <main.h>

/*

LCD_
RS  <P4.0>	   
WR  <P4.1>     
E   <P4.2>
要求:P4.0,4.1,4.2设置为推拉输出;  
P5口设置为带弱上拉的漏极输出,3.3V电平标准即可

*/

unsigned char code dig[]={"0123456789"};

void lcd_delay()
{	unsigned char delayTime;
	for(delayTime=100;delayTime>0;delayTime--);
}
  
/* 返回值Status:	当前地址计数器的值.	*/
unsigned char LCDBusyWait()							//等待LCD就绪
{
	unsigned char Status;
	P4&=0xfe;  //11111110,LCD_RS=0
    lcd_delay();
 	
	P4|=0x02;//00000010,LCD_RW=1
    lcd_delay();  
	
	P5 = 0xFF;
	P4|=0x04;//00000100,LCD_E=1

	lcd_delay();   
	Status=P5;
	P4&=0xfB;//11111011,LCD_E=0

	while(Status & 0x80)
	{
        lcd_delay(); 
		P4|=0x04;//00000100,LCD_E=1
        lcd_delay();  
		Status=P5;
		lcd_delay(); 
		P4&=0xfB;//11111011,LCD_E=0

	}
	P4&=0xfd;//11111101,LCD_RW=0

	return Status;
}

void WriteLCD_Data(unsigned char Data)			//向LCD写入一个字节的数据
{
	LCDBusyWait();
	P4|=0x01;//00000001,LCD_RW=0,LCD_RS=1

	lcd_delay();	 
	P5 = Data;
	lcd_delay();
	P4|=0x04;//00000100,LCD_E=1

	lcd_delay();
	P4&=0xfB;//11111011,LCD_E=0

}

void WriteLCD_Command(unsigned char Command)	//向LCD写入一个字节的命令
{
	LCDBusyWait();
	P4&=0xFE;//11111110,LCD_RS=0

	lcd_delay();
	P5 = Command;
	lcd_delay();
	P4|=0x04;//00000100,LCD_E=1

	lcd_delay();
	P4&=0xfB;//11111011,LCD_E=0

}

//改变地址,实现了逐行显示
unsigned char ChangeAddress(unsigned char StartAddress)
{
	switch(StartAddress)
	{
		case 0x87:WriteLCD_Command(0x90);StartAddress=0x90;break;
		case 0x8F:WriteLCD_Command(0x98);StartAddress=0x98;break;
		case 0x97:WriteLCD_Command(0x88);StartAddress=0x88;break;
		default:StartAddress+=1;
	}
	return StartAddress;
}

/*****************************显示字符串***************************************/

void WriteLCD(unsigned char StartAddress,unsigned char Size,unsigned char Charactors[])
{
	unsigned char *i=Charactors;	  //字符串的首地址
	WriteLCD_Command(StartAddress);
	if(Size) 		//Size不为0
	{
	//	bit Over=0;
		while(i<(Charactors+Size))		//判断字符串结尾
		{

			WriteLCD_Data(*i);
			i++;
			//WriteLCD_Data(*i);
			//i++;
			StartAddress=ChangeAddress(StartAddress); //改变地址,实现了逐行显示
		}
	}
	else			//Size为0
	{
		while(*i)						//判断字符串结尾,*i为0代表结束
		{
			WriteLCD_Data(*i);
			i++;
			WriteLCD_Data(*i);
			i++;
			StartAddress=ChangeAddress(StartAddress);
		}
	}
}
/****************************显示数字********************************/

void Show_num(unsigned char address,unsigned int num)
{
 unsigned char k,j,i=0;
 unsigned char w_data[10];
 WriteLCD_Command(address); 
 //WriteLCD(0x90,0,"     ");
 do
   {
    w_data[i++]=num%10;
	num=num/10;
	j=i;
   }while(num!=0);
     
	for(k=j;k>0;k--)
	{	
		WriteLCD_Data(dig[w_data[k-1]]);
	}
}