90pc-mcu.c

单片机开发资料光盘-双龙-686M.zip

#include<io8515.h>
#pragma interrupt_handler uart_rec:10
#define clrcs     PORTC&=~0x10;   
#define setcs     PORTC|=0x10;
#define clrclk    PORTC&=~0x08;
#define setclk    PORTC|=0x08;



void delay(unsigned char mst)  //延时子程序
 {  unsigned char i;
     for (i = 1; i<mst; i++)
			;
 }

void send(unsigned char temp)  //发送子程序
{
 unsigned char i;
 clrcs
 delay(150);
 clrclk
 for(i=8;i>0;i--)
  {
   PORTC=(temp&0x80)?PORTC|0x04:PORTC&0xfb;
   setclk
   delay(10);
   clrclk
   delay(10);
   temp=temp<<1;
  }
 PORTC&=~0x04;  
} 

void write279(unsigned char cmd1, unsigned char cmd2)
{
	send(cmd1);
	send(cmd2);                              
	setcs;
}

 receive(void)              //接收子程序
{
 unsigned char i,rec_buff;
 DDRC&=~0x04;
 PORTC&=~0x04;
 delay(150); 
 for(i=8;i>0;i--)
 { 
  rec_buff=rec_buff<<1;
  setclk
  delay(10);
  rec_buff=(PINC&0x04)==0?rec_buff&0xfe:rec_buff|0x01;
  clrclk
  delay(10);
 } 
 DDRC|=0x04;
 PORTC&=~0x04;
 return rec_buff;	
}


keyscan(void)                //键扫子程序
{
 static signed char keycode,keypress=0;
 if((PINC&0x02)==0)
 {
  if(keypress==0)
  {
   send(0x15);
   keycode=receive();
   setcs
   keypress=1;
  } 
   return 0xff;
 }

 if(keypress==1)
 {
  keypress=0;
  return   keycode; 
 }
 return 0xff;
}

 

 
void main()
{
 unsigned char i,j,c;
 DDRC=0xfd;
 PORTC=0xf7;
 send(0xa4);
 setcs
 UBRR=51;
 UCR=0x98;
 SREG|=0x80;
waitkey:
    c=keyscan();
	if(c!=0xff)
	{
     write279(0xcf,c);
	 USR&=~0x40;
	 UDR=c;
	 while(!(USR&0x40));
	 USR&=~0x40;
	}
	goto waitkey;

}

void uart_rec()             
{
 unsigned char i;
 if((USR&0x10)==1) return;
 i=UDR; 
 write279(0xc9,i/16);
 write279(0xc8,i%16);
}