hd7279.c

ｈｄ７２７９驱动程序

/****************************************
模块名称：HD7279

******************************************/

#include <includes.h>




//7279延时
void long_delay(void)
{
	unsigned char i;
	for (i=0;i<0x30;i++);
}
void short_delay(void)
{
	unsigned char i;
	for (i=0;i<8;i++);
}
//7279子程序
void send_byte( unsigned char out_byte)
{
	unsigned char i;
	CS=0;
	long_delay();
	for (i=0;i<8;i++)
	{
		if (out_byte&0x80)
		{
			DAT=1;
		}
		else
		{
			DAT=0;
		}
	CLK=1;
	short_delay();
	CLK=0;
	short_delay();
	out_byte=out_byte*2;
	}
	DAT=0;
}

//读键盘码
unsigned char receive_byte(void)
{
	unsigned char i, in_byte;
   
   send_byte(0x15);
   DAT=1; 
	long_delay();
	for (i=0;i<8;i++)
	{         
		CLK=1;
		short_delay();
		in_byte=in_byte*2;
		if(DAT)
		{
			in_byte=in_byte|0x01;
		}
		CLK=0;
		short_delay();
	}
	DAT=0;
	return (in_byte);
}
/***********************************************/
/*      按键处理: KEY_DEAL()     	       */
/*      传递参数：无                           */
/***********************************************/
void KEY_DEAL(void)
{
	unsigned char Key;
	Key = receive_byte();
	
}