123.c

KEIL C51 串口通信源码

#include <AT89X51.H>
#include < intrins.h > 
#include < stdio.h >
#define INBUF_LEN 2 //数据长度 
unsigned char inbuf1[INBUF_LEN]; 
unsigned char checksum,count3;
#define uchar unsigned char 
bit read_flag= 0 ; 
void delay(int ms) 
{ 
uchar i; 
while(ms--) 
{ 
for(i=0;i<250;i++) 
{ 
_nop_(); 
_nop_(); 
_nop_(); 
_nop_(); 
} 
} 
} 
void init_serialcomm( void ) 
{ 
SCON = 0x50 ; //SCON: serail mode 1, 8-bit UART, enable ucvr 
TMOD |= 0x20 ; //TMOD: timer 1, mode 2, 8-bit reload 
PCON |= 0x80 ; //SMOD=1; 
TH1 = 0xF4 ; //Baud:4800 fosc=11.0592MHz 
IE |= 0x90 ; //Enable Serial Interrupt 
TR1 = 1 ; // timer 1 run 
// TI=1; 
} 
//向串口发送一个字符 
void send_char_com( unsigned char ch) 
{ 
SBUF=ch; 
while (TI== 0 ); 
TI= 0 ; 
} 
//向串口发送一个字符串，strlen为该字符串长度 
void send_string_com( unsigned char *str, unsigned int strlen) 
{ 
unsigned int k= 0 ; 
do 
{ 
send_char_com(*(str + k)); 
k++; 
} while (k < strlen); 
} 

//串口接收中断函数 
void serial () interrupt 4 using 3 
{ 
if (RI) 
{ 
unsigned char ch; 
RI = 0 ; 
ch=SBUF; 

count3= 0 ; 
inbuf1[count3]=ch; 
checksum= ch ; 



read_flag= 1 ; //如果串口接收的数据达到INBUF_LEN个，且校验没错， 
//就置位取数标志 

} 
} 
 

main() 
{ 
init_serialcomm(); //初始化串口 
while ( 1 ) 
{ 
if (read_flag) //如果取数标志已置位，就将读到的数从串口发出 
{ 
read_flag= 0 ; //取数标志清0 

if (inbuf1[0]=='h')
{
inbuf1[0]='h';
inbuf1[1]='1';
send_string_com(inbuf1,INBUF_LEN); 
}
if (inbuf1[0]=='b')
{
inbuf1[0]='t';
inbuf1[1]='1';
send_string_com(inbuf1,INBUF_LEN);
delay(500);
inbuf1[0]='t';
inbuf1[1]='2';
send_string_com(inbuf1,INBUF_LEN);
delay(500);
inbuf1[0]='t';
inbuf1[1]='3';
send_string_com(inbuf1,INBUF_LEN);
delay(500);
inbuf1[0]='t';
inbuf1[1]='4';
send_string_com(inbuf1,INBUF_LEN);
delay(500);
inbuf1[0]='t';
inbuf1[1]='5';
send_string_com(inbuf1,INBUF_LEN); 
delay(500);
inbuf1[0]='t';
inbuf1[1]='6';
send_string_com(inbuf1,INBUF_LEN); 
}






} 
} 
}