可可-
Linux串口读写：
#include <stdio.h> /*标准输入输出定义*/
#include <stdlib.h> /*标准函数库定义*/
#include <unistd.h> /*Unix 标准函数定义*/
#include <sys/types.h>
#include <sys/stat.h>
#include "string.h"
#include <fcntl.h> /*文件控制定义*/
#include <termios.h> /*PPSIX 终端控制定义*/
#include <errno.h> /*错误号定义*/
#define FALSE -1
#define TRUE 0
/*********************************************************************/
int OpenDev(char *Dev)
{
int fd = open( Dev, O_RDWR | O_NOCTTY ); //| O_NOCTTY | O_NDELAY
if (-1 == fd)
{
perror("Can"t Open Serial Port");
return -1;
}
else
return fd;
}
/**
*@brief 设置串口通信速率
*@param fd 类型 int 打开串口的文件句柄
*@param speed 类型 int 串口速度
*@return void
*/
int speed_arr[] = { B38400, B19200, B9600, B4800, B2400, B1200, B300,
B38400, B19200, B9600, B4800, B2400, B1200, B300, };
int name_arr[] = {38400, 19200, 9600, 4800, 2400, 1200, 300, 38400,
19200, 9600, 4800, 2400, 1200, 300, };
void set_speed(int fd, int speed)
{
int i;
int status;
struct termios Opt;
tcgetattr(fd, &Opt);
for ( i= 0; i < sizeof(speed_arr) / sizeof(int); i++) {
if (speed == name_arr[i]) {
tcflush(fd, TCIOFLUSH);
cfsetispeed(&Opt, speed_arr[i]);
cfsetospeed(&Opt, speed_arr[i]);
status = tcsetattr(fd, TCSANOW, &Opt);
if (status != 0) {
perror("tcsetattr fd1");
return;
}
tcflush(fd,TCIOFLUSH);
}
}
}
/**
*@brief 设置串口数据位，停止位和效验位
*@param fd 类型 int 打开的串口文件句柄
*@param databits 类型 int 数据位 取值 为 7 或者8
*@param stopbits 类型 int 停止位 取值为 1 或者2
*@param parity 类型 int 效验类型 取值为N,E,O,,S
*/
int set_Parity(int fd,int databits,int stopbits,int parity)
{
struct termios options;
options.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); /*Input*/
options.c_oflag &= ~OPOST; /*Output*/
if ( tcgetattr( fd,&options) != 0) {
perror("SetupSerial 1");
return(FALSE);
}
options.c_cflag &= ~CSIZE;
switch (databits) /*设置数据位数*/
{
case 7:
options.c_cflag |= CS7;
break;
case 8:
options.c_cflag |= CS8;
break;
default:
fprintf(stderr,"Unsupported data size/n"); return (FALSE);
}
switch (parity)
{
case "n":
case "N":
options.c_cflag &= ~PARENB; /* Clear parity enable */
options.c_iflag &= ~INPCK; /* Enable parity checking */
break;
case "o":
case "O":
options.c_cflag |= (PARODD | PARENB); /* 设置为奇效验*/
options.c_iflag |= INPCK; /* Disnable parity checking */
break;
case "e":
case "E":
options.c_cflag |= PARENB; /* Enable parity */
options.c_cflag &= ~PARODD; /* 转换为偶效验*/
options.c_iflag |= INPCK; /* Disnable parity checking */
break;
case "S":
case "s": /*as no parity*/
options.c_cflag &= ~PARENB;
options.c_cflag &= ~CSTOPB;break;
default:
fprintf(stderr,"Unsupported parity/n");
return (FALSE);
}
/* 设置停止位*/
switch (stopbits)
{
case 1:
options.c_cflag &= ~CSTOPB;
break;
case 2:
options.c_cflag |= CSTOPB;
break;
default:
fprintf(stderr,"Unsupported stop bits/n");
return (FALSE);
}
/* Set input parity option */
if (parity != "n")
options.c_iflag |= INPCK;
tcflush(fd,TCIFLUSH);
options.c_cc[VTIME] = 150; /* 设置超时15 seconds*/
options.c_cc[VMIN] = 0; /* Update the options and do it NOW */
if (tcsetattr(fd,TCSANOW,&options) != 0)
{
perror("SetupSerial 3");
return (FALSE);
}
return (TRUE);
}
int main(int argc, char **argv)
{
int fd;
int nread;
char buff[512];
char *dev = "/dev/ttyS0"; //串口二
fd = OpenDev(dev);
set_speed(fd,4800);
if (set_Parity(fd,8,1,"N") == FALSE)
{
printf("Set Parity Error/n");
exit (0);
}
int i;
i = getchar();
if ( i == "1")
{
while (1) //循环读取数据
{
while((nread = read(fd, buff, 512))>0)
{
printf("/nLen %d/n",nread);
buff[nread+1] = "/0";
printf( "/n%s", buff);
}
}
}
if ( i == "2")
{
while (1) //循环写入数据
{
gets(buff);
printf("------buff--->%s<--------/n",buff);
int num = strlen(buff);
printf("--------num---->%d<--------------/n",num);
if ( num > 0)
{
printf("Wirte num not NULL./r/n");
nread = write(fd, buff ,num);
if(nread == -1)
{
printf("Wirte sbuf error./n");
}
printf("--nread---->%d<-----------/n",nread);
}
}
}
close(fd);
//exit (0);
}
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