akiserial.h

linux下串口通信例子

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

//#include "akiserial.h"


/*****************************
 * 功能：设置串口函数
 * 入口：（fd，波特率，数据位，奇偶校验，停止位）
 *****************************/
int set_opt(int fd,int nSpeed,int nBits,char nEvent,int nStop)
{
	struct termios newtio,oldtio;
	/*保存测试现有串口参数设置，在这里如果串口号出错，会有相关的出错信息*/
	if(tcgetattr(fd,&oldtio)!=0) {
		perror("SetupSerial 1");
		return -1;
	}

	bzero(&newtio,sizeof(newtio));

	/*步骤一：设置字符大小*/
	newtio.c_cflag |= CLOCAL | CREAD;
	newtio.c_cflag &= ~CSIZE;

	/*设置停止位*/
	switch(nBits) {
		case 7:	newtio.c_cflag |= CS7;
				break;
		case 8:	newtio.c_cflag |= CS8;
				break;
	}

	/*设置奇偶校验位*/
	switch(nEvent) {
		case 'O':	//奇数
					newtio.c_cflag |= PARENB;
					newtio.c_cflag |= PARODD;
					newtio.c_iflag |= (INPCK | ISTRIP);
					break;
		case 'E':	//偶数
					newtio.c_iflag |= (INPCK | ISTRIP);
					newtio.c_cflag |= PARENB;
					newtio.c_cflag &= ~PARODD;
					
					break;
		case 'N':	//无奇偶校验位
					newtio.c_cflag &= ~PARENB;
					break;
	}

	/*设置波特率*/
	switch (nSpeed)
	{
		case 2400:	
					cfsetispeed(&newtio,B2400);
					cfsetospeed(&newtio,B2400);
					break;
		case 4800:	
					cfsetispeed(&newtio,B4800);
					cfsetospeed(&newtio,B4800);
					break;
		case 9600:	
					cfsetispeed(&newtio,B9600);
					cfsetospeed(&newtio,B9600);
					break;
		case 115200:	
					cfsetispeed(&newtio,B115200);
					cfsetospeed(&newtio,B115200);
					break;
		case 460800:	
					cfsetispeed(&newtio,B460800);
					cfsetospeed(&newtio,B460800);
					break;
		default :
					cfsetispeed(&newtio,B9600);
					cfsetospeed(&newtio,B9600);
					break;
	}

	/*设置停止位*/
	if(nStop==1) {
		newtio.c_cflag &= ~CSTOPB;
	}
	else if (nStop==2) {
		newtio.c_cflag |= CSTOPB;
	}

	/*设置等待时间和最小接收字符*/
	newtio.c_cc[VTIME]=0;
	newtio.c_cc[VMIN]=0;

	/*处理未接收字符*/
	tcflush(fd,TCIFLUSH);
	
	/*激活新配置*/
	if((tcsetattr(fd,TCSANOW,&newtio))!=0) {
		perror("COM set error\n");
		return -1;
	}
	//printf("Set Done!\n");
	return 0;
}

/*****************************
 * 功能：打开串口函数
 *****************************/
int open_port(int fd,int comport)
{
	char *dev[]={"/dev/ttyS0","/dev/ttyS1","/dev/ttyS2","/dev/ttyS3","/dev/ttyS4","/dev/ttyS5","/dev/ttyS6","/dev/ttyS7"};
	long vdisable;
	
	fd=open(dev[comport-1],O_RDWR|O_NOCTTY|O_NDELAY);
	if(fd==-1) {
		perror("Can't Open Serial Port\n");
		return -1;
	}

	/*恢复串口为阻塞状态*/
	if(fcntl(fd,F_SETFL,0)<0) {
		printf("fcntl failed!\n");
	}
	else printf("fcntl=%d\n",fcntl(fd,F_SETFL,0));

	/*测试是否为终端设备*/
	if(isatty(STDIN_FILENO)==0) {
		printf("standard input is not a terminal device\n");
	}
	else printf("isatty success!\n");
	printf("fd-open=%d\n",fd);
	return fd;
}

/*****************************
 * 功能：16进制ascii字符转数值 
 * [例]'A'转换后是0x0a
 *****************************/
char Hex2Char(char c)
{
	if((c>='0')&&(c<='9'))
		return c-0x30;
	else if((c>='A')&&(c<='F'))
		return c-'A'+10;
	else if((c>='a')&&(c<='f'))
		return c-'a'+10;
	else 
		return 0x10;
}