4
启动参数 来选择内核采用哪个端口
init=/linuxrc console=ttySAC1,115200
noinitrd root=/dev/mtdblock2 init=/linuxrc console=ttySAC0,115200
noinitrd root=/dev/mtdblock2 init=/linuxrc console=s3c2410_serial0,115200
测试程序:
1
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <errno.h>
#include <termios.h>
#include <sys/time.h>
#include <signal.h>
#include <string.h>
#include <fcntl.h>
#include <asm/param.h>
#include "pthread.h"
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，在这里如果串口号等出错，会有相关的出错信息
if ( tcgetattr( fd,&oldtio) != 0)
{
perror("SetupSerial 1");
return -1;
}
//extern void bzero(void *s, int n); 置字节字符串s的前n个字节为零
bzero( &newtio, sizeof( newtio ) );
//设置字符大小
newtio.c_cflag |= CLOCAL | CREAD;
newtio.c_cflag &= ~CSIZE;
//设置数据位
switch( nBits )
{
case 7:
newtio.c_cflag |= CS7;
break;
case 8:
newtio.c_cflag |= CS8;
break;
}
//设置校验位
switch( nEvent )
{
case 'O':
newtio.c_cflag |= PARENB;
newtio.c_cflag |= PARODD;
newtio.c_iflag |= (INPCK | ISTRIP);
break;
case 'E':
newtio.c_iflag |= (INPCK | ISTRIP);
newtio.c_cflag |= PARENB;
newtio.c_cflag &= ~PARODD;
break;
case 'N':
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;
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");//打印com set error及出错原因
return -1;
}
printf("set done!\n");
return 0;
}