iar14-2master.c

手把手教你学AVR单片机C程序设计实验程序

#include<iom16.h>
#define uchar unsigned char	//变量类型的宏定义
#define uint  unsigned int	
#define SPIF 7
#define SS 4
#define xtal 8
#define CLR_BIT(x,y) (x&=~(1<<y))
#define SET_BIT(x,y) (x|=(1<<y))
uchar __flash SEG7[10]={0x3f,0x06,0x5b,0x4f,0x66,	
                0x6d,0x7d,0x07,0x7f,0x6f};
uchar __flash ACT[8]={0xfe,0xfd,0xfb,0xf7,0xef,0xdf,0xbf,0x7f};	
uchar TXbuffer[10]={0,1,2,3,4,5,6,7,8,9};
uchar i=0;
//****************************************
void Delay_1ms(void)		
{ uint i;
 for(i=1;i<(uint)(xtal*143-2);i++)
    ;
}
//=============================================
void Delay_nms(uint n)		
{
 uint i=0;
   while(i<n)
   {
    Delay_1ms();
    i++;
   }
}
/*******************************/
void port_init(void)
{
 PORTA = 0x00; 
 DDRA  = 0xFF;
 PORTC = 0xFF; 
 DDRC  = 0xFF;
 PORTB = 0x10; 
 DDRB  = 0xB0;
}
/*******************************/
void spi_init(void)
{
 SPCR = 0x51; 
}
/******************************/
void SPI_MasterTransmit(char cData)
{
  SPDR=cData;
  while(!(SPSR&(1<<SPIF))) ;
  CLR_BIT(SPSR,SPIF);
}
/*********************************************/
void main(void)
{ 
  uchar temp=0;
  Delay_nms(100);	
  port_init();
  spi_init();
  while(1)
  {
    CLR_BIT(PORTB,SS);
    SPI_MasterTransmit(TXbuffer[i]);
    temp=SPDR;
    SET_BIT(PORTB,SS);
    PORTA = SEG7[TXbuffer[i]]; 
    PORTC = ACT[0];
    Delay_nms(500);	
    while(temp!=0x55);
    temp=0;
    if(++i>9)i=0;
  }
}