uart1t.c

周立公smartarm2200开发板的串口例子

#define IN_UART1

#include "config.h"

//#include <asm/arch/hardware.h>
//#include <asm/io.h>

#include     <stdio.h>      /* stand input and output... */
//#include     <stdlib.h>     /* stand lib */
//#include     <unistd.h>     /* UNIX stand function */
//#include     <sys/types.h>  /**/
//#include     <sys/stat.h>   /**/
#include     <fcntl.h>      /* file controle */
#include     <termios.h>    /*PPSIX terminal controle */
#include     <errno.h>      /* error */

/************ set baud ********************/

void set_speed(int fd, int speed)
{
    int   i;
    int   status;
    struct termios Opt;

    tcgetattr(fd, &Opt);  // get attribute of serial port
    tcflush(fd, TCIOFLUSH);
    cfsetispeed(&Opt, speed);
    cfsetospeed(&Opt, speed);

    status = tcsetattr(fd, TCSANOW, &Opt);  // set attribute
    if  (status != 0)
    {
        perror("tcsetattr fd1");
        return;
    }
    tcflush(fd,TCIOFLUSH);
}


/*********** set data format: databits,stopbits and parity **********/

int set_data_format(int fd,int databits,int stopbits,int parity)
{
    struct termios opt;

    if( tcgetattr(fd, &opt)  !=  0)
    {
  	perror("SetupSerial 1");
  	return(FALSE);
    }
    opt.c_cflag &= ~CSIZE;

    switch (databits)
    {
 	
        case 5:
  		opt.c_cflag |= CS5;
  		break;
        case 6:
  		opt.c_cflag |= CS6;
  		break;
        case 7:
  		opt.c_cflag |= CS7;
  		break;
  	case 8:
		opt.c_cflag |= CS8;
		break;
	default:
		fprintf(stderr,"Unsupported data size\n");
		return (FALSE);
    }
    switch (parity)
    {
        case 'n':
        case 'N':
		opt.c_cflag &= ~PARENB;   /* Clear parity enable */
		opt.c_iflag &= ~INPCK;     /* Enable parity checking */
		break;
	case 'o':
	case 'O':
		opt.c_cflag |= (PARODD | PARENB);  /* parity checking */ 
		opt.c_iflag |= INPCK;      /* Disnable parity checking */
		break;
	case 'e':
	case 'E':
		opt.c_cflag |= PARENB;     /* Enable parity */
		opt.c_cflag &= ~PARODD;   /*  */  
		opt.c_iflag |= INPCK;       /* Disnable parity checking */
		break;
//	case 'S':
//	case 's':  /*as no parity*/
//		opt.c_cflag &= ~PARENB;
//		opt.c_cflag &= ~CSTOPB;
//		break;
	default:
		fprintf(stderr,"Unsupported parity\n");
		return (FALSE);
    }
       
    switch (stopbits)
    {
        case 1:
  		opt.c_cflag &= ~CSTOPB;
		break;
	case 2:
		opt.c_cflag |= CSTOPB;
		break;
	default:
		fprintf(stderr,"Unsupported stop bits\n");
		return (FALSE);
    }

    /* Set input parity option */
    if (parity != 'n')
     	opt.c_iflag |= INPCK;
    opt.c_cc[VTIME] = 100; // 10 seconds
    opt.c_cc[VMIN] = 0;

    tcflush(fd, TCIFLUSH); /* Update the options and do it NOW */
    if (tcsetattr(fd, TCSANOW, &opt) != 0)
    {
  	perror("SetupSerial 3");
	return (FALSE);
    }
 
    return (TRUE);
 }
/************* main() ********************/
int main()
{
    int fd;
    int temp, PinSel0Save;
    int8 rcv[32];

 //   temp = inl(PINSEL0);        // long int
 //   PinSel0Save =  temp & (0x0f << 16); // save PINSEL0 setting
 //   temp &= ~(0x0f << 16);              // connect UART0
 //   temp |= (0x05 << 16);
 //   outl(temp, PINSEL0);                // write PINSEL0 
    
    fd = open("/dev/ttyS1", O_RDWR);  // read and write

    if(fd == -1)
    {
	printf("Can't open ttyS1!\n");
	exit(0);
    }
    set_speed(fd,B115200);   // set baud 115200

    if (set_data_format(fd,8,1,'N')== FALSE)
    { 
        printf("Data format Error!\n");
        exit(1);
    } 
  
    write(fd, "Hello World!\n", 13) ;
    write(fd, "Hello World!\n", 13) ;

    read(fd, rcv, 8);
    printf("\n");
    write(fd, rcv, 8);
    printf("\n");

    /* disconnect UART1 */
  //  temp = inl(PINSEL0);
  //  temp &= ~(0x0f << 16);
  //  temp |= PinSel0Save;
  //  outl(temp, PINSEL0);

    close(fd);
    return(0);
}