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手把手教你学AVR单片机C程序设计实验程序

#include <iom16.h>
#include<intrinsics.h>
#define UDRE 5
#define RXC 7
/***************************************/
void port_init(void)
{
 PORTA = 0xFF; 
 DDRA  = 0x00; 
 PORTB = 0xFF; 
 DDRB  = 0xFF; 
 PORTC = 0xFF; 
 DDRC  = 0x00; 
 PORTD = 0xFF; 
 DDRD  = 0x02; 
}
/**************************************/
void uart0_init(void) 
{
 UCSRB = 0x00; 
 UCSRA = 0x02;
 UCSRC = 0x06;
 UBRRL = 0x67; 
 UBRRH = 0x00; 
 UCSRB = 0x18;
}

void init_devices(void) 
{
 __disable_interrupt(); 
 port_init();
 uart0_init();
 }
/********************************/
void uart0_send(unsigned char i)
{
while(!(UCSRA&(1<<UDRE)));
UDR=i;
}
/************************************************/
unsigned char uart0_receive(void) 
{
while(!(UCSRA&(1<<RXC)));
return UDR;
}
/******************************************/
void main(void) 
{
unsigned char temp;
init_devices();
 while(1) 
 {
 temp=uart0_receive();
 PORTB=~temp; 
 uart0_send(temp);
 }
}