Question

怎么用C语言中断方式实现串口的读写?

我想对计算机串口进行中断操作,不知怎样设置寄存器,大虾们可否提供思路?

Answer 1

＃include <stdio.h>
＃include <dos.h>
＃include <time.h>

#define LSB 0
#define MSB 1

#define RXR 0
#define TXR 0
#define IER 1
#define IIR 2
#define LCR 3
#define MCR 4
#define LSR 5
#define MSR 6

#define Com1_base 0x3f8
#define uchar unsigned char

volatile uchar inputData;
volatile uchar onInput = 0x00;
volatile uchar onOutput = 0x00;
volatile uchar inputdata[256]; /*设设置接收缓冲区大小*/
volatile unsigned int count; /*中断接收的数据数目*/
int datacount;/*当前已发送数据条数*/

void interrupt (*OldVect)(); /*函数是用来获取中断处理程序的入口地址的*/
void interrupt SerialISR();

void InitCom()
{
uchar inttemp;
/*设置波特率什么的*/
outportb(Com1_base+LCR,0x80); /*使LCR的高位为1，以便读取其它寄存器*/
outportb(Com1_base+LSB,0x0c); /*除数锁存器（低8位）DLL*/
outportb(Com1_base+MSB,0x00); /*除数锁存器（高8位）DLH 产生2400波特率*/
outportb(Com1_base+LCR,0x03); /*8位数据，1位停止位，无校验*/
outportb(Com1_base+IER,0x01); /*接收采用中断方式*/

/*设置中断向量*/
OldVect = getvect(0x0c); /*函数是用来获取中断处理程序的入口地址的*/
disable();
inttemp = inportb(0x21)&0xef;
outportb(0x21,inttemp);
setvect(0x0c,SerialISR); /*设置SerialISR的中断入口地址为0X0C*/
enable();
}

void CloseCom()
{
disable();
outportb(Com1_base+IER,0x00); *禁止中断*/
outportb(Com1_base,0x00);
outportb(0x21,inportb(0x21)|~(0xef));
setvect(0x0c,OldVect);
}

void interrupt SerialISR()
{
/*串口中断服务代码*/
inputData = inportb(Com1_base+RXR);
onInput = 0x01;
inputdata[count]=inputData;
count++;
/*服务代码结束*/
outportb(0x20,0x20); /*中断结束的代码*/
}

void SendChar(uchar key)
{
while( ((inportb(Com1_base + LSR)) & 0x40) == 0);
outportb(Com1_base + TXR,key);
}
/*...........延时函数......................*/
void delay(unsigned int n)
{
unsigned int i,k;
for(k=0;k<n;k++)
{
for(i=1;i<1142;i++)
;
}
}

/*........CDMA命令发送函数.................*/
void CDMA_CommandSend(char *p,unsigned int n)
{

int i,k,m,l;
int flag=0;
int selse_flag=0; int selse_flag_1=0;
int selse_flag1=0;int selse_flag1_1=0;
time_t start,end;
double dif=0;
char a;

uchar bExit_flag = 0x00;
count=0;
while(!bExit_flag)
{
count=0;
for(i=0;i<n;i++)
{SendChar(*p);delay(9000);p++;}

/*..........等待2S..................*/
time (&start);
dif=0;
while(dif<2)
{
delay(9000);
time (&end);
dif = difftime (end,start);
}
if(count>14)
{
time (&start);
dif=0;
while(dif<3)
{
delay(9000);
time (&end);
dif = difftime (end,start);
}
}

/*..........判断发送命令是否成功..................*/
for(m=0;m<count;m++)
{
if(count>10)
{
for(l=0;l<count;l++)
{
if(inputdata[l-1]=='N'&&inputdata[l-2]=='E'&&inputdata[l-3]=='P'&&inputdata[l-4]=='O'&&inputdata[l-5]=='P'&&inputdata[l-6]=='P'&&inputdata[l-7]=='P'&&inputdata[l-8]=='V') { selse_flag_1=1;}
if(inputdata[l-1]=='N'&&inputdata[l-2]=='E'&&inputdata[l-3]=='P'&&inputdata[l-4]=='O'&&inputdata[l-5]=='P'&&inputdata[l-6]=='C'&&inputdata[l-7]=='T'&&inputdata[l-8]=='V') { selse_flag1_1=1;}
}

if(selse_flag_1==1){if(inputdata[m-1]=='3'&&inputdata[m-2]=='3'&&inputdata[m-3]==':'&&inputdata[m-4]=='T') selse_flag=1;}
if(selse_flag1_1==1){if(inputdata[m-1]=='0'&&inputdata[m-2]==','&&inputdata[m-3]=='1'&&inputdata[m-4]==':'&&inputdata[m-5]=='N') selse_flag1=1;}

if(selse_flag_1==1||selse_flag1_1==1)
{
if(selse_flag==1) {if(inputdata[m-1]=='0'&&inputdata[m-2]==':'&&inputdata[m-3]=='N'&&inputdata[m-4]=='E') flag=1;}
if(selse_flag1==1) {if(inputdata[m-1]=='0'&&inputdata[m-2]==','&&inputdata[m-3]=='1'&&inputdata[m-4]==':'&&inputdata[m-5]=='S') flag=1;}
}
else {if(inputdata[m-1]=='O'&&inputdata[m]=='K') {flag=1; }}
}
else {if(inputdata[m-1]=='O'&&inputdata[m]=='K') flag=1; }
}
if(flag==1){bExit_flag = 0x01;}
else {p=p-n; }

for(i=0;i<count;i++) printf("%c",inputdata[i]);
/*........按空格停止测试.............................*/
if(kbhit()){a=getch(); if(a==' '){CloseCom(); exit(1);}}

}
}

/*........数据测试发送任务.....................*/
void Data_Send(char *pcomd,int n,char *pdata,int m)
{
int i,k,l;time_t start,end;
double dif=0;
count=0;
for(i=0;i<n;i++)
{
SendChar(*pcomd);delay(9000);pcomd++;
}
time (&start);
dif=0;
while(dif<0.2)
{
delay(9000);
time (&end);
dif = difftime (end,start);
}

for(l=0;l<m;l++)
{
SendChar(*pdata);pdata++;
}

printf("The data num:%d",datacount);
datacount++;
}

void main()
{int i;char a;
/*........模块测试命令..................................*/
uchar CDMA_COMMAND_1[]={"at\r"};
uchar CDMA_COMMAND_2[]={"atz\r"};
uchar CDMA_COMMAND_3[]={"ate1v1\r"};
uchar CDMA_COMMAND_4[]={"AT+CRM=1;+CPS=33;+CMUX=1;+CTA=0\r"};
uchar CDMA_COMMAND_5[]={"AT+VPPPOPEN\r"};
uchar CDMA_COMMAND_6[]={"AT+VTCPOPEN=1,\"60.63.42.129\",1234\r"};
uchar CDMA_COMMAND_7[]={"AT+VTCPSEND=1,20\r"};
uchar CDMA_DATA[]={"ABCDEFGHIJKLMNOPQRST"};
uchar CDMA_COMMAND_9[]={"AT+VPPPCLOSE\r"};
uchar CDMA_COMMAND_8[]={"AT+VTCPCLOSE=1\r"};
uchar bExit_flag1 = 0x00;
time_t start,end;
double dif=0;
InitCom();/*初始化端口1*/
inputData = inportb(Com1_base+RXR);
while(!bExit_flag1)
{
/*.................................................................*/
if(kbhit()) /*按任意键开始测试CDMA*/
{
/*.............................................................. ...*/

/*.........发送TCP断开命令.....................................*/
CDMA_CommandSend(CDMA_COMMAND_8,strlen(CDMA_COMMAND_8));
/*.........发送PPP断开命令......................................*/
CDMA_CommandSend(CDMA_COMMAND_9,strlen(CDMA_COMMAND_9));

/*.........发送AT命令..........................................*/
CDMA_CommandSend(CDMA_COMMAND_1,strlen(CDMA_COMMAND_1));
/*.........发送ATZ命令.........................................*/
CDMA_CommandSend(CDMA_COMMAND_2,strlen(CDMA_COMMAND_2));
/*.........发送ATE1V1命令......................................*/
CDMA_CommandSend(CDMA_COMMAND_3,strlen(CDMA_COMMAND_3));
/*.........发送AT初始化命令....................................*/
CDMA_CommandSend(CDMA_COMMAND_4,strlen(CDMA_COMMAND_4));
/*.........发送PPP拔号命令.....................................*/
CDMA_CommandSend(CDMA_COMMAND_5,strlen(CDMA_COMMAND_5));
/*.........发送网络连接命令....................................*/
CDMA_CommandSend(CDMA_COMMAND_6,strlen(CDMA_COMMAND_6));
/*.........发送数据............................................*/
datacount=0;
while(1)
{
Data_Send(CDMA_COMMAND_7,strlen(CDMA_COMMAND_7),CDMA_DATA,strlen(CDMA_DATA));

time (&start);
dif=0;
while(dif<0.2)
{
delay(9000);
time (&end);
dif = difftime (end,start);
}

if(kbhit()){a=getch(); if(a==' '){bExit_flag1 = 0x01; break;}}
}
/*.........发送TCP断开命令.....................................*/
for(i=0;i<3;i++)
CDMA_CommandSend(CDMA_COMMAND_8,strlen(CDMA_COMMAND_8));
/*.........发送PPP断开命令......................................*/
for(i=0;i<3;i++)
CDMA_CommandSend(CDMA_COMMAND_9,strlen(CDMA_COMMAND_9));

bExit_flag1 = 0x01;
}

/*.................................................................*/

}
CloseCom(); /*关闭端口1*/
printf("Bye~.\n");
}