uart_test.tar.gz_Linux UART te_linux uart

#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); }