单片机IO口模拟RS232串口C语言程序.doc

单片机I/O口模拟RS232串口C语言程序
#include <>
sbit BT_SND =P1^0;
sbit BT_REC =P1^1;
/**********************************************
IO 口模拟232通讯程序
使用两种方式的C程序占用定时器0
**********************************************/
#define MODE_QUICK
#define F_TM F0
#define TIMER0_ENABLE TL0=TH0; TR0=1;
#define TIMER0_DISABLE TR0=0;
sbit ACC0= ACC^0;
sbit ACC1= ACC^1;
sbit ACC2= ACC^2;
sbit ACC3= ACC^3;
sbit ACC4= ACC^4;
sbit ACC5= ACC^5;
sbit ACC6= ACC^6;
sbit ACC7= ACC^7;
void IntTimer0() interrupt 1
{
F_TM=1;
}
//发送一个字符
void PSendChar(unsigned char inch)
{
#ifdef MODE_QUICK
ACC=inch;
F_TM=0;
BT_SND=0; //start bit
TIMER0_ENABLE; //启动
while(!F_TM);
BT_SND=ACC0; //先送出低位
F_TM=0;
while(!F_TM);
BT_SND=ACC1;
F_TM=0;
while(!F_TM);
BT_SND=ACC2;
F_TM=0;
while(!F_TM);
BT_SND=ACC3;
F_TM=0;
while(!F_TM);
BT_SND=ACC4;
F_TM=0;
while(!F_TM);
BT_SND=ACC5;
F_TM=0;
while(!F_TM);
BT_SND=ACC6;
F_TM=0;
while(!F_TM);
BT_SND=ACC7;
F_TM=0;
while(!F_TM);
BT_SND=1;
F_TM=0;
while(!F_TM);
TIMER0_DISABLE; //停止timer
#else
unsigned char ii;
ii=0;
F_TM=0;
BT_SND=0; //start bit
TIMER0_ENABLE; //启动
while(!F_TM);
while(ii<8)
{
if(inch&1)
{
BT_SND=1;
}
else
{
BT_SND=0;
}
F_TM=0;
while(!F_TM);
ii++;
inch>>=1;
}
BT_SND=1;
F_TM=0;
while(!F_TM);
#endif
TIMER0_DISABLE; //停止timer
}
//接收一个字符
unsigned char PGetChar()
{
#ifdef MODE_QUICK
TIM