bmain.c

一个关于avr单片机串口通信的一个简单例子 对于avr初学者 来说 可以一看

//ICC-AVR application builder : 2008-4-11 10:29:01
// Target : M8
// Crystal: 8.0000Mhz

#include <iom8v.h>
#include <macros.h>
void port_init(void)
{
 PORTB = 0xff;
 DDRB  = 0x00;
 PORTC = 0xff; //m103 output only
 DDRC  = 0x00;
 PORTD = 0x00;
 DDRD  = 0x00;
}

//UART0 initialize
// desired baud rate: 19200
// actual: baud rate:19231 (0.2%)
void uart0_init(void)
{
 UCSRB = 0x00; //disable while setting baud rate
 UCSRA = 0x00;
 UCSRC = BIT(URSEL) | 0x06;
 UBRRL = 0x19; //set baud rate lo
 UBRRH = 0x00; //set baud rate hi
 UCSRB = 0xD8;
}

void USART_Transmit( unsigned char data )/*  等待发送缓冲器为空 */
{
  while ( !( UCSRA & (1<<UDRE)) )/* 将数据放入缓冲器，发送数据 */
  ;
  UDR = data;
}
unsigned char USART_Receive( void )
{
 /* 等待接收数据*/

while ( !(UCSRA & (1<<RXC)) )
;
 /*从缓冲器中获取并返回数据*/
 
return UDR;
}

#pragma interrupt_handler uart0_rx_isr:iv_USART0_RXC
void uart0_rx_isr(void)
{
 //uart has received a character in UDR
}

#pragma interrupt_handler uart0_tx_isr:iv_USART0_TXC
void uart0_tx_isr(void)
{
 //character has been transmitted
}

//call this routine to initialize all peripherals
void init_devices(void)
{
 //stop errant interrupts until set up
 CLI(); //disable all interrupts
 port_init();
 uart0_init();

 MCUCR = 0x00;
 GICR  = 0x00;
 TIMSK = 0x00; //timer interrupt sources
 SEI(); //re-enable interrupts
 //all peripherals are now initialized
}



void delay(unsigned long m)//延迟
{
 int i,j;
 for(i=0;i<m;i++)
  {}
}
/*******************************************************************************
字符定义：“6”    0x08															
           		   																
*******************************************************************************/

void main(void)
{
 unsigned int a,b=100,c=200;
 init_devices();
 while(1)
  {
  if(!(PINC&0x01))
  {
   USART_Transmit(0xaa);
    delay(800);
   USART_Transmit(a);
   USART_Transmit(b);
   USART_Transmit(c);
    delay(800);
   USART_Transmit(0x51);
   USART_Transmit(0x59);
   USART_Transmit(0x97);
    delay(800);
   USART_Transmit(0xff);//xor
   USART_Transmit(0x55);
   delay(65535);
   a++;b++;c++;
  }
  }
}