#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <termios.h>
#include <fcntl.h>
#include <sys/types.h>
typedef unsigned char u8;
typedef unsigned int u32;
int speed_arr[] =
{ B9600, B19200, B57600, B115200, B500000, B1000000, B2000000 };
int name_arr[] = { 9600, 19200, 57600, 115200, 500000, 1000000, 2000000 };
char *dev_name[] = { "/dev/ttyS0", "/dev/ttyS1", "/dev/ttyS2", "/dev/ttyS3" };
void
setspeed (int fd, int speed)
{
int i;
int status;
printf ("set baudrate:%d\n", speed);
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 fd");
return;}
}
tcflush (fd, TCIOFLUSH);
}
} //set speed of uart
int
main (int argc, char *argv[])
{
int fd, rt;
int w=0;
int n_read, n_write;
int i, n = 0;
int speed = 0; //baudrate
u8 w_buf[100];
char r_buf[100];
char *dev={0};
for(i=0;i<8;i++)
{
w_buf[i]=i+1;
}
//read baudrate
while ((rt = getopt (argc, argv, "hwb:c:")) >= 0)
switch (rt)
{
case 'h':
printf ("Usage:%s [-h] [-w] [-b] [baudrate] [-c] [/dev/ttyS*] \n"
"\t-b set the uart baudrate!\n"
"\t-w write the uart before read it!\n"
"\t-c the uart NO.", argv[0]);
return 0;
case 'b':
speed = atoi (optarg);
printf ("get baudrate:%d\n", speed);
break;
case 'w':
w=1;
break;
case 'c':
dev = dev_name[atoi (optarg)];
break;
}
//open uart
if ((fd = open (dev, O_RDWR | O_NONBLOCK)) == -1)
{
perror ("open uart:");
return 0;
}
if (!speed)
{
printf ("error:set baudrate first\n");
return 0;
}
//set this uart baudrate
setspeed (fd, speed);
//init uart
struct termios options;
if ((tcgetattr (fd, &options)) != 0)
{
printf ("tcgetattr failed!");
return 1;
}
printf ("get cflag:%08x\n", options.c_cflag);
// options.c_cflag |= (CLOCAL | CREAD);
options.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG);
options.c_iflag &= ~(IXON | IXOFF | IXANY);
options.c_oflag &= ~OPOST;
// options.c_oflag &= ~CRTSCTS;
// options.c_cflag &= ~ CSTOPB;
// options.c_cflag &= ~PARENB;
tcsetattr (fd, TCSANOW, &options);
//read and write uart
while (1)
{
if (w)
n_write = write (fd, w_buf, 8);
if ((n_read = read (fd, r_buf, 8)) > 0)
{
for (i = 0; i < n_read; i++)
{
printf ("%02x ", r_buf[i]);
n++;
if (n == 8)
{
printf ("\n");
n = 0;
}
}
}
}
close (fd);
}
