Linux串口测试

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mb6603ea7fc8a1f 2024-03-28 14:56:53 博主文章分类：Linux

文章标签 #include ios #define 文章分类 JavaScript 前端开发

1. 打开自动回车换行\0D\0A

echo "12345" > /dev/ttyS0

2. 关闭自动回车换行\0D\0A

echo -n "12345" > /dev/ttyS0

3. 十六进制输入

echo -ne "\xFF\xFF\xFF" > /dev/ttyS0

4. 修改波特率115200 8 N 1

stty -F /dev/ttyS0 speed 115200 cs8 -parenb -cstopb -echo

测试程序

receive.c

#include   <stdio.h>     
#include   <stdlib.h>   
#include   <unistd.h>     
#include   <sys/types.h> 
#include   <sys/stat.h>  
#include   <fcntl.h>    
#include   <termios.h>  
#include   <errno.h>    
#include   <string.h>

#define TRUE 1

void setTermios(struct termios * pNewtio, int uBaudRate)
{
    bzero(pNewtio, sizeof(struct termios)); /* clear struct for new port settings */
    //8N1
    pNewtio->c_cflag = uBaudRate | CS8 | CREAD | CLOCAL;
    pNewtio->c_iflag = IGNPAR;
    pNewtio->c_oflag = 0;
    pNewtio->c_lflag = 0; //non ICANON
    /*
     initialize all control characters
     default values can be found in /usr/include/termios.h, and
     are given in the comments, but we don't need them here
     */
    pNewtio->c_cc[VINTR] = 0; /* Ctrl-c */
    pNewtio->c_cc[VQUIT] = 0; /* Ctrl-\ */
    pNewtio->c_cc[VERASE] = 0; /* del */
    pNewtio->c_cc[VKILL] = 0; /* @ */
    pNewtio->c_cc[VEOF] = 4; /* Ctrl-d */
    pNewtio->c_cc[VTIME] = 5; /* inter-character timer, timeout VTIME*0.1 */
    pNewtio->c_cc[VMIN] = 0; /* blocking read until VMIN character arrives */
    pNewtio->c_cc[VSWTC] = 0; /* '\0' */
    pNewtio->c_cc[VSTART] = 0; /* Ctrl-q */
    pNewtio->c_cc[VSTOP] = 0; /* Ctrl-s */
    pNewtio->c_cc[VSUSP] = 0; /* Ctrl-z */
    pNewtio->c_cc[VEOL] = 0; /* '\0' */
    pNewtio->c_cc[VREPRINT] = 0; /* Ctrl-r */
    pNewtio->c_cc[VDISCARD] = 0; /* Ctrl-u */
    pNewtio->c_cc[VWERASE] = 0; /* Ctrl-w */
    pNewtio->c_cc[VLNEXT] = 0; /* Ctrl-v */
    pNewtio->c_cc[VEOL2] = 0; /* '\0' */
}
 
#define BUFSIZE 7

int main(int argc, char **argv)
{
    int fd;
    int nread;
    char buff[BUFSIZE];
    struct termios oldtio, newtio;
    struct timeval tv;
    char *dev ="/dev/ttyS2";
    fd_set rfds; 
	int i = 0;
	
    if ((fd = open(dev, O_RDWR | O_NOCTTY))<0){		printf("err: can't open serial port!\n");
		return -1;
    }

    tcgetattr(fd, &oldtio); /* save current serial port settings */
    setTermios(&newtio, B38400);
    tcflush(fd, TCIFLUSH);
    tcsetattr(fd, TCSANOW, &newtio);

	tv.tv_sec=30;
	tv.tv_usec=0;

	while (TRUE){
		printf("wait...\n");

		FD_ZERO(&rfds);
		FD_SET(fd, &rfds);

		if (select(1+fd, &rfds, NULL, NULL, NULL)>0){
			if (FD_ISSET(fd, &rfds)){
				nread=read(fd, buff, BUFSIZE);		printf("readlength=%d\n", nread);
				for (i = 0; i < BUFSIZE; i++){
					printf ("0x%02x ", buff[i]);
				}
				printf("\n");
			}
		}
	}

	tcsetattr(fd, TCSANOW, &oldtio);
	close(fd);
}

send.c

#include   <stdio.h>     
#include   <stdlib.h>   
#include   <unistd.h>     
#include   <sys/types.h> 
#include   <sys/stat.h>  
#include   <fcntl.h>    
#include   <termios.h>
#include   <errno.h>    
#include   <string.h>

void setTermios(struct termios * pNewtio, int uBaudRate)
{
    bzero(pNewtio, sizeof(struct termios)); /* clear struct for new port settings */
    //8N1
    pNewtio->c_cflag = uBaudRate | CS8 | CREAD | CLOCAL;
    pNewtio->c_iflag = IGNPAR;
    pNewtio->c_oflag = 0;
    pNewtio->c_lflag = 0; //non ICANON
    /*
     initialize all control characters
     default values can be found in /usr/include/termios.h, and
     are given in the comments, but we don't need them here
    */
    pNewtio->c_cc[VINTR] = 0; /* Ctrl-c */
    pNewtio->c_cc[VQUIT] = 0; /* Ctrl-\ */
    pNewtio->c_cc[VERASE] = 0; /* del */
    pNewtio->c_cc[VKILL] = 0; /* @ */
    pNewtio->c_cc[VEOF] = 4; /* Ctrl-d */
    pNewtio->c_cc[VTIME] = 5; /* inter-character timer, timeout VTIME*0.1 */
    pNewtio->c_cc[VMIN] = 0; /* blocking read until VMIN character arrives */
    pNewtio->c_cc[VSWTC] = 0; /* '\0' */
    pNewtio->c_cc[VSTART] = 0; /* Ctrl-q */
    pNewtio->c_cc[VSTOP] = 0; /* Ctrl-s */
    pNewtio->c_cc[VSUSP] = 0; /* Ctrl-z */
    pNewtio->c_cc[VEOL] = 0; /* '\0' */
    pNewtio->c_cc[VREPRINT] = 0; /* Ctrl-r */
    pNewtio->c_cc[VDISCARD] = 0; /* Ctrl-u */
    pNewtio->c_cc[VWERASE] = 0; /* Ctrl-w */
    pNewtio->c_cc[VLNEXT] = 0; /* Ctrl-v */
    pNewtio->c_cc[VEOL2] = 0; /* '\0' */
}

int main(int argc, char **argv)
{
    int fd;
    int nCount, nTotal, i;
    struct termios oldtio, newtio;
	
    char *dev ="/dev/ttyS2";
	
    //if ((argc!=3) || (sscanf(argv[1], "%d", &nTotal) != 1)){
	//	printf("err: need tow arg!\n");
	//	return -1;
    //}

    if ((fd = open(dev, O_RDWR | O_NOCTTY))<0){		printf("err: can't open serial port!\n");
		return -1;
    }

    tcgetattr(fd, &oldtio); /* save current serial port settings */
	
    setTermios(&newtio, B38400);
    tcflush(fd, TCIFLUSH);
    tcsetattr(fd, TCSANOW, &newtio);

	//for (i=0; i<nTotal; i++){
	//	nCount=write(fd, argv[2], strlen(argv[2]));
	//	printf("send data\n");
	//	sleep(1);
	//}
    char cmd[7] = {0xFF, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00};
	
	cmd[2] = 0x00;
	cmd[3] = 0x04;		// 0x04, left; 0x02, right; 0x08, up; 0x10, down
	cmd[4] = 0x2F;
	cmd[5] = 0x00;
	cmd[6] = ((cmd[1] + cmd[2] + cmd[3] + cmd[4] + cmd[5])) & 0xFF;	printf ("check sum: 0x%02x\n", cmd[6]);
	int ret = write (fd, cmd, 7);

	printf ("Running...\n");
	sleep (4);	

	cmd[2] = 0x00;
	cmd[3] = 0x00;			//left and right stop
	cmd[4] = 0x2F;
	cmd[5] = 0x00;
	cmd[6] = ((cmd[1] + cmd[2] + cmd[3] + cmd[4] + cmd[5])) & 0xFF;	printf ("check sum: 0x%02x\n", cmd[6]);
	ret = write (fd, cmd, 7);

	cmd[2] = 0x00;
	cmd[3] = 0x51;			//get pos
	cmd[4] = 0x00;
	cmd[5] = 0x00;
	cmd[6] = ((cmd[1] + cmd[2] + cmd[3] + cmd[4] + cmd[5])) & 0xFF;	printf ("check sum: 0x%02x\n", cmd[6]);
	ret = write (fd, cmd, 7);
	
	sync();

	tcsetattr(fd, TCSANOW, &oldtio);
	close(fd);

    return 0;
}