Code:
rs232.h:
/*
***************************************************************************
*
* Author: Teunis van Beelen
*
* Copyright (C) 2005, 2006, 2007, 2008, 2009 Teunis van Beelen
*
* [email protected]
*
***************************************************************************
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
***************************************************************************
*
* This version of GPL is at http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt
*
***************************************************************************
*/
#ifndef rs232_INCLUDED
#define rs232_INCLUDED
#ifdef __cplusplus
extern "C" {
#endif
#include <stdio.h>
#include <string.h>
#ifdef __linux__
#include <termios.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <limits.h>
#else
#include <windows.h>
#include <WinDef.h>
#include <io.h>
#endif
int OpenComport(int, int);
int PollComport(int, unsigned char *, int);
int SendByte(int, unsigned char);
int SendBuf(int, unsigned char *, int);
void CloseComport(int);
void cprintf(int, const char *);
int IsCTSEnabled(int);
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif
rs232.c:
Code:
#include "rs232.h"
#include <stdio.h>
//#include <conio.h>
#include <stdlib.h>
#include <string.h>
#include <dos.h>
#include <windows.h>
#include <winbase.h>
#include <WinDef.h>
#include <io.h>
#ifdef __linux__ /* Linux */
int Cport[22],
error;
struct termios new_port_settings,
old_port_settings[22];
char comports[22][13]={"/dev/ttyS0","/dev/ttyS1","/dev/ttyS2","/dev/ttyS3","/dev/ttyS4","/dev/ttyS5",
"/dev/ttyS6","/dev/ttyS7","/dev/ttyS8","/dev/ttyS9","/dev/ttyS10","/dev/ttyS11",
"/dev/ttyS12","/dev/ttyS13","/dev/ttyS14","/dev/ttyS15","/dev/ttyUSB0",
"/dev/ttyUSB1","/dev/ttyUSB2","/dev/ttyUSB3","/dev/ttyUSB4","/dev/ttyUSB5"};
int OpenComport(int comport_number, int baudrate)
{
int baudr;
if((comport_number>21)||(comport_number<0))
{
printf("illegal comport number\n");
return(1);
}
switch(baudrate)
{
case 50 : baudr = B50;
break;
case 75 : baudr = B75;
break;
case 110 : baudr = B110;
break;
case 134 : baudr = B134;
break;
case 150 : baudr = B150;
break;
case 200 : baudr = B200;
break;
case 300 : baudr = B300;
break;
case 600 : baudr = B600;
break;
case 1200 : baudr = B1200;
break;
case 1800 : baudr = B1800;
break;
case 2400 : baudr = B2400;
break;
case 4800 : baudr = B4800;
break;
case 9600 : baudr = B9600;
break;
case 19200 : baudr = B19200;
break;
case 38400 : baudr = B38400;
break;
case 57600 : baudr = B57600;
break;
case 115200 : baudr = B115200;
break;
case 230400 : baudr = B230400;
break;
case 460800 : baudr = B460800;
break;
case 500000 : baudr = B500000;
break;
case 576000 : baudr = B576000;
break;
case 921600 : baudr = B921600;
break;
case 1000000 : baudr = B1000000;
break;
default : printf("invalid baudrate\n");
return(1);
break;
}
Cport[comport_number] = open(comports[comport_number], O_RDWR | O_NOCTTY | O_NDELAY);
if(Cport[comport_number]==-1)
{
perror("unable to open comport ");
return(1);
}
error = tcgetattr(Cport[comport_number], old_port_settings + comport_number);
if(error==-1)
{
close(Cport[comport_number]);
perror("unable to read portsettings ");
return(1);
}
memset(&new_port_settings, 0, sizeof(new_port_settings)); /* clear the new struct */
new_port_settings.c_cflag = baudr | CS8 | CLOCAL | CREAD;
new_port_settings.c_iflag = IGNPAR;
new_port_settings.c_oflag = 0;
new_port_settings.c_lflag = 0;
new_port_settings.c_cc[VMIN] = 0; /* block untill n bytes are received */
new_port_settings.c_cc[VTIME] = 0; /* block untill a timer expires (n * 100 mSec.) */
error = tcsetattr(Cport[comport_number], TCSANOW, &new_port_settings);
if(error==-1)
{
close(Cport[comport_number]);
perror("unable to adjust portsettings ");
return(1);
}
return(0);
}
int PollComport(int comport_number, unsigned char *buf, int size)
{
int n;
#ifndef __STRICT_ANSI__ /* __STRICT_ANSI__ is defined when the -ansi option is used for gcc */
if(size>SSIZE_MAX) size = (int)SSIZE_MAX; /* SSIZE_MAX is defined in limits.h */
#else
if(size>4096) size = 4096;
#endif
n = read(Cport[comport_number], buf, size);
return(n);
}
int SendByte(int comport_number, unsigned char byte)
{
int n;
n = write(Cport[comport_number], &byte, 1);
if(n<0) return(1);
return(0);
}
int SendBuf(int comport_number, unsigned char *buf, int size)
{
return(write(Cport[comport_number], buf, size));
}
void CloseComport(int comport_number)
{
close(Cport[comport_number]);
tcsetattr(Cport[comport_number], TCSANOW, old_port_settings + comport_number);
}
/*
Constant Description
TIOCM_LE DSR (data set ready/line enable)
TIOCM_DTR DTR (data terminal ready)
TIOCM_RTS RTS (request to send)
TIOCM_ST Secondary TXD (transmit)
TIOCM_SR Secondary RXD (receive)
TIOCM_CTS CTS (clear to send)
TIOCM_CAR DCD (data carrier detect)
TIOCM_CD Synonym for TIOCM_CAR
TIOCM_RNG RNG (ring)
TIOCM_RI Synonym for TIOCM_RNG
TIOCM_DSR DSR (data set ready)
*/
int IsCTSEnabled(int comport_number)
{
int status;
status = ioctl(Cport[comport_number], TIOCMGET, &status);
if(status&TIOCM_CTS) return(1);
else return(0);
}
#else /* windows */
HANDLE Cport[16];
char comports[16][10]={"\\\\.\\COM1", "\\\\.\\COM2", "\\\\.\\COM3", "\\\\.\\COM4",
"\\\\.\\COM5", "\\\\.\\COM6", "\\\\.\\COM7", "\\\\.\\COM8",
"\\\\.\\COM9", "\\\\.\\COM10", "\\\\.\\COM11", "\\\\.\\COM12",
"\\\\.\\COM13", "\\\\.\\COM14", "\\\\.\\COM15", "\\\\.\\COM16"};
char baudr[9600];
int OpenComport(int comport_number, int baudrate)
{
if((comport_number>15)||(comport_number<0))
{
printf("illegal comport number\n");
return(1);
}
switch(baudrate)
{
case 110 : strcpy(baudr, "baud=110 data=8 parity=N stop=1");
break;
case 300 : strcpy(baudr, "baud=300 data=8 parity=N stop=1");
break;
case 600 : strcpy(baudr, "baud=600 data=8 parity=N stop=1");
break;
case 1200 : strcpy(baudr, "baud=1200 data=8 parity=N stop=1");
break;
case 2400 : strcpy(baudr, "baud=2400 data=8 parity=N stop=1");
break;
case 4800 : strcpy(baudr, "baud=4800 data=8 parity=N stop=1");
break;
case 9600 : strcpy(baudr, "baud=9600 data=8 parity=N stop=1");
break;
case 19200 : strcpy(baudr, "baud=19200 data=8 parity=N stop=1");
break;
case 38400 : strcpy(baudr, "baud=38400 data=8 parity=N stop=1");
break;
case 57600 : strcpy(baudr, "baud=57600 data=8 parity=N stop=1");
break;
case 115200 : strcpy(baudr, "baud=115200 data=8 parity=N stop=1");
break;
case 128000 : strcpy(baudr, "baud=128000 data=8 parity=N stop=1");
break;
case 256000 : strcpy(baudr, "baud=256000 data=8 parity=N stop=1");
break;
default : printf("invalid baudrate\n");
return(1);
break;
}
Cport[comport_number] = CreateFileA(comports[comport_number],
GENERIC_READ|GENERIC_WRITE,
0, /* no share */
NULL, /* no security */
OPEN_EXISTING,
0, /* no threads */
NULL); /* no templates */
if(Cport[comport_number]==INVALID_HANDLE_VALUE)
{
printf("unable to open comport\n");
return(1);
}
DCB port_settings;
memset(&port_settings, 0, sizeof(port_settings)); /* clear the new struct */
port_settings.DCBlength = sizeof(port_settings);
if(!BuildCommDCBA(baudr, &port_settings))
{
printf("unable to set comport dcb settings\n");
CloseHandle(Cport[comport_number]);
return(1);
}
if(!SetCommState(Cport[comport_number], &port_settings))
{
printf("unable to set comport cfg settings\n");
CloseHandle(Cport[comport_number]);
return(1);
}
COMMTIMEOUTS Cptimeouts;
Cptimeouts.ReadIntervalTimeout = MAXDWORD;
Cptimeouts.ReadTotalTimeoutMultiplier = 0;
Cptimeouts.ReadTotalTimeoutConstant = 0;
Cptimeouts.WriteTotalTimeoutMultiplier = 0;
Cptimeouts.WriteTotalTimeoutConstant = 0;
if(!SetCommTimeouts(Cport[comport_number], &Cptimeouts))
{
printf("unable to set comport time-out settings\n");
CloseHandle(Cport[comport_number]);
return(1);
}
return(0);
}
int PollComport(int comport_number, unsigned char *buf, int size)
{
int n;
if(size>4096) size = 4096;
/* added the void pointer cast, otherwise gcc will complain about */
/* "warning: dereferencing type-punned pointer will break strict aliasing rules" */
ReadFile(Cport[comport_number], buf, size, (LPDWORD)((void *)&n), NULL);
return(n);
}
int SendByte(int comport_number, unsigned char byte)
{
int n;
WriteFile(Cport[comport_number], &byte, 1, (LPDWORD)((void *)&n), NULL);
if(n<0) return(1);
return(0);
}
int SendBuf(int comport_number, unsigned char *buf, int size)
{
int n;
if(WriteFile(Cport[comport_number], buf, size, (LPDWORD)((void *)&n), NULL))
{
return(n);
}
return(-1);
}
void CloseComport(int comport_number)
{
CloseHandle(Cport[comport_number]);
}
int IsCTSEnabled(int comport_number)
{
int status;
GetCommModemStatus(Cport[comport_number], (LPDWORD)((void *)&status));
if(status&MS_CTS_ON) return(1);
else return(0);
}
#endif
void cprintf(int comport_number, const char *text) /* sends a string to serial port */
{
while(*text != 0) SendByte(comport_number, *(text++));
}