c语言串口4800怎么设置 如何在c程序中重新设置串口波特率

#include#define uchar unsigned char

#define uint unsigned int

#define SYSCLK 11059200

uintBAUDRATE;

uchar flag,a;

unsigned char flag_on;

void main()

{

SCON=0x50;

TMOD=0x20;

TH1=0xfd;

TL1=0xfd;

TR1=1;

EA=1;

ES=1;

while(1)

{

if(flag==1)

{

flag=0;//标志位清0

ES=0;

TI=1;

switch(flag_on)

{

case 0: BAUDRATE=4800;

TH1=-SYSCLK/BAUDRATE/32/12;

TL1=-SYSCLK/BAUDRATE/32/12;

printf("baudrate is %d\n"，BAUDRATE);

break;

case 1: BAUDRATE=9600;

TH1=-SYSCLK/BAUDRATE/32/12;

TL1=-SYSCLK/BAUDRATE/32/12;

printf("baudrate is %d\n",BAUDRATE);

break;

case 2: BAUDRATE=19200;

TH1=-SYSCLK/BAUDRATE/32/12;

TL1=-SYSCLK/BAUDRATE/32/12;

printf("baudrate is %d\n",BAUDRATE);

break;

}

while(!TI);

TI=0;

ES=1;

}

}

}

void ser() interrupt 4

{

RI=0;

a=SBUF;

flag=1;

if(a==1)

flag_on=0;

else if(a==2)

flag_on=1;

else

flag_on=2;

}

这个是错的请朋友们帮修改下！