src/lib/rs232/rs232.c

   1 /*
   2 ***************************************************************************
   3 *
   4 * Author: Teunis van Beelen
   5 *
   6 * Copyright (C) 2005 - 2019 Teunis van Beelen
   7 *
   8 * Email: teuniz@protonmail.com
   9 *
  10 ***************************************************************************
  11 *
  12 * This program is free software: you can redistribute it and/or modify
  13 * it under the terms of the GNU General Public License as published by
  14 * the Free Software Foundation, either version 3 of the License, or
  15 * (at your option) any later version.
  16 *
  17 * This program is distributed in the hope that it will be useful,
  18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 * GNU General Public License for more details.
  21 *
  22 * You should have received a copy of the GNU General Public License
  23 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  24 *
  25 ***************************************************************************
  26 */
  27
  28
  29 /* Last revision: May 31, 2019 */
  30 /* Added support for hardware flow control using RTS and CTS lines */
  31 /* For more info and how to use this library, visit: http://www.teuniz.net/RS-232/ */
  32
  33
  34 #include "rs232.h"
  35
  36
  37 #if defined(__linux__) || defined(__FreeBSD__)   /* Linux & FreeBSD */
  38
  39 #define RS232_PORTNR  38
  40
  41
  42 int Cport[RS232_PORTNR],
  43     error;
  44
  45 struct termios new_port_settings,
  46        old_port_settings[RS232_PORTNR];
  47
  48 char *comports[RS232_PORTNR]={"/dev/ttyS0","/dev/ttyS1","/dev/ttyS2","/dev/ttyS3","/dev/ttyS4","/dev/ttyS5",
  49                        "/dev/ttyS6","/dev/ttyS7","/dev/ttyS8","/dev/ttyS9","/dev/ttyS10","/dev/ttyS11",
  50                        "/dev/ttyS12","/dev/ttyS13","/dev/ttyS14","/dev/ttyS15","/dev/ttyUSB0",
  51                        "/dev/ttyUSB1","/dev/ttyUSB2","/dev/ttyUSB3","/dev/ttyUSB4","/dev/ttyUSB5",
  52                        "/dev/ttyAMA0","/dev/ttyAMA1","/dev/ttyACM0","/dev/ttyACM1",
  53                        "/dev/rfcomm0","/dev/rfcomm1","/dev/ircomm0","/dev/ircomm1",
  54                        "/dev/cuau0","/dev/cuau1","/dev/cuau2","/dev/cuau3",
  55                        "/dev/cuaU0","/dev/cuaU1","/dev/cuaU2","/dev/cuaU3"};
  56
  57 int RS232_OpenComport(int comport_number, int baudrate, const char *mode, int flowctrl)
  58 {
  59   int baudr,
  60       status;
  61
  62   if((comport_number>=RS232_PORTNR)||(comport_number<0))
  63   {
  64     printf("illegal comport number\n");
  65     return(1);
  66   }
  67
  68   switch(baudrate)
  69   {
  70     case      50 : baudr = B50;
  71                    break;
  72     case      75 : baudr = B75;
  73                    break;
  74     case     110 : baudr = B110;
  75                    break;
  76     case     134 : baudr = B134;
  77                    break;
  78     case     150 : baudr = B150;
  79                    break;
  80     case     200 : baudr = B200;
  81                    break;
  82     case     300 : baudr = B300;
  83                    break;
  84     case     600 : baudr = B600;
  85                    break;
  86     case    1200 : baudr = B1200;
  87                    break;
  88     case    1800 : baudr = B1800;
  89                    break;
  90     case    2400 : baudr = B2400;
  91                    break;
  92     case    4800 : baudr = B4800;
  93                    break;
  94     case    9600 : baudr = B9600;
  95                    break;
  96     case   19200 : baudr = B19200;
  97                    break;
  98     case   38400 : baudr = B38400;
  99                    break;
 100     case   57600 : baudr = B57600;
 101                    break;
 102     case  115200 : baudr = B115200;
 103                    break;
 104     case  230400 : baudr = B230400;
 105                    break;
 106     case  460800 : baudr = B460800;
 107                    break;
 108     case  500000 : baudr = B500000;
 109                    break;
 110     case  576000 : baudr = B576000;
 111                    break;
 112     case  921600 : baudr = B921600;
 113                    break;
 114     case 1000000 : baudr = B1000000;
 115                    break;
 116     case 1152000 : baudr = B1152000;
 117                    break;
 118     case 1500000 : baudr = B1500000;
 119                    break;
 120     case 2000000 : baudr = B2000000;
 121                    break;
 122     case 2500000 : baudr = B2500000;
 123                    break;
 124     case 3000000 : baudr = B3000000;
 125                    break;
 126     case 3500000 : baudr = B3500000;
 127                    break;
 128     case 4000000 : baudr = B4000000;
 129                    break;
 130     default      : printf("invalid baudrate\n");
 131                    return(1);
 132                    break;
 133   }
 134
 135   int cbits=CS8,
 136       cpar=0,
 137       ipar=IGNPAR,
 138       bstop=0;
 139
 140   if(strlen(mode) != 3)
 141   {
 142     printf("invalid mode \"%s\"\n", mode);
 143     return(1);
 144   }
 145
 146   switch(mode[0])
 147   {
 148     case '8': cbits = CS8;
 149               break;
 150     case '7': cbits = CS7;
 151               break;
 152     case '6': cbits = CS6;
 153               break;
 154     case '5': cbits = CS5;
 155               break;
 156     default : printf("invalid number of data-bits '%c'\n", mode[0]);
 157               return(1);
 158               break;
 159   }
 160
 161   switch(mode[1])
 162   {
 163     case 'N':
 164     case 'n': cpar = 0;
 165               ipar = IGNPAR;
 166               break;
 167     case 'E':
 168     case 'e': cpar = PARENB;
 169               ipar = INPCK;
 170               break;
 171     case 'O':
 172     case 'o': cpar = (PARENB | PARODD);
 173               ipar = INPCK;
 174               break;
 175     default : printf("invalid parity '%c'\n", mode[1]);
 176               return(1);
 177               break;
 178   }
 179
 180   switch(mode[2])
 181   {
 182     case '1': bstop = 0;
 183               break;
 184     case '2': bstop = CSTOPB;
 185               break;
 186     default : printf("invalid number of stop bits '%c'\n", mode[2]);
 187               return(1);
 188               break;
 189   }
 190
 191 /*
 192 http://pubs.opengroup.org/onlinepubs/7908799/xsh/termios.h.html
 193
 194 http://man7.org/linux/man-pages/man3/termios.3.html
 195 */
 196
 197   Cport[comport_number] = open(comports[comport_number], O_RDWR | O_NOCTTY | O_NDELAY);
 198   if(Cport[comport_number]==-1)
 199   {
 200     perror("unable to open comport ");
 201     return(1);
 202   }
 203
 204   /* lock access so that another process can't also use the port */
 205   if(flock(Cport[comport_number], LOCK_EX | LOCK_NB) != 0)
 206   {
 207     close(Cport[comport_number]);
 208     perror("Another process has locked the comport.");
 209     return(1);
 210   }
 211
 212   error = tcgetattr(Cport[comport_number], old_port_settings + comport_number);
 213   if(error==-1)
 214   {
 215     close(Cport[comport_number]);
 216     flock(Cport[comport_number], LOCK_UN);  /* free the port so that others can use it. */
 217     perror("unable to read portsettings ");
 218     return(1);
 219   }
 220   memset(&new_port_settings, 0, sizeof(new_port_settings));  /* clear the new struct */
 221
 222   new_port_settings.c_cflag = cbits | cpar | bstop | CLOCAL | CREAD;
 223   if(flowctrl)
 224   {
 225     new_port_settings.c_cflag |= CRTSCTS;
 226   }
 227   new_port_settings.c_iflag = ipar;
 228   new_port_settings.c_oflag = 0;
 229   new_port_settings.c_lflag = 0;
 230   new_port_settings.c_cc[VMIN] = 0;      /* block untill n bytes are received */
 231   new_port_settings.c_cc[VTIME] = 0;     /* block untill a timer expires (n * 100 mSec.) */
 232
 233   cfsetispeed(&new_port_settings, baudr);
 234   cfsetospeed(&new_port_settings, baudr);
 235
 236   error = tcsetattr(Cport[comport_number], TCSANOW, &new_port_settings);
 237   if(error==-1)
 238   {
 239     tcsetattr(Cport[comport_number], TCSANOW, old_port_settings + comport_number);
 240     close(Cport[comport_number]);
 241     flock(Cport[comport_number], LOCK_UN);  /* free the port so that others can use it. */
 242     perror("unable to adjust portsettings ");
 243     return(1);
 244   }
 245
 246 /* http://man7.org/linux/man-pages/man4/tty_ioctl.4.html */
 247
 248   if(ioctl(Cport[comport_number], TIOCMGET, &status) == -1)
 249   {
 250     tcsetattr(Cport[comport_number], TCSANOW, old_port_settings + comport_number);
 251     flock(Cport[comport_number], LOCK_UN);  /* free the port so that others can use it. */
 252     perror("unable to get portstatus");
 253     return(1);
 254   }
 255
 256   status |= TIOCM_DTR;    /* turn on DTR */
 257   status |= TIOCM_RTS;    /* turn on RTS */
 258
 259   if(ioctl(Cport[comport_number], TIOCMSET, &status) == -1)
 260   {
 261     tcsetattr(Cport[comport_number], TCSANOW, old_port_settings + comport_number);
 262     flock(Cport[comport_number], LOCK_UN);  /* free the port so that others can use it. */
 263     perror("unable to set portstatus");
 264     return(1);
 265   }
 266
 267   return(0);
 268 }
 269
 270
 271 int RS232_PollComport(int comport_number, unsigned char *buf, int size)
 272 {
 273   int n;
 274
 275   n = read(Cport[comport_number], buf, size);
 276
 277   if(n < 0)
 278   {
 279     if(errno == EAGAIN)  return 0;
 280   }
 281
 282   return(n);
 283 }
 284
 285
 286 int RS232_SendByte(int comport_number, unsigned char byte)
 287 {
 288   int n = write(Cport[comport_number], &byte, 1);
 289   if(n < 0)
 290   {
 291     if(errno == EAGAIN)
 292     {
 293       return 0;
 294     }
 295     else
 296     {
 297       return 1;
 298     }
 299   }
 300
 301   return(0);
 302 }
 303
 304
 305 int RS232_SendBuf(int comport_number, unsigned char *buf, int size)
 306 {
 307   int n = write(Cport[comport_number], buf, size);
 308   if(n < 0)
 309   {
 310     if(errno == EAGAIN)
 311     {
 312       return 0;
 313     }
 314     else
 315     {
 316       return -1;
 317     }
 318   }
 319
 320   return(n);
 321 }
 322
 323
 324 void RS232_CloseComport(int comport_number)
 325 {
 326   int status;
 327
 328   if(ioctl(Cport[comport_number], TIOCMGET, &status) == -1)
 329   {
 330     perror("unable to get portstatus");
 331   }
 332
 333   status &= ~TIOCM_DTR;    /* turn off DTR */
 334   status &= ~TIOCM_RTS;    /* turn off RTS */
 335
 336   if(ioctl(Cport[comport_number], TIOCMSET, &status) == -1)
 337   {
 338     perror("unable to set portstatus");
 339   }
 340
 341   tcsetattr(Cport[comport_number], TCSANOW, old_port_settings + comport_number);
 342   close(Cport[comport_number]);
 343
 344   flock(Cport[comport_number], LOCK_UN);  /* free the port so that others can use it. */
 345 }
 346
 347 /*
 348 Constant  Description
 349 TIOCM_LE        DSR (data set ready/line enable)
 350 TIOCM_DTR       DTR (data terminal ready)
 351 TIOCM_RTS       RTS (request to send)
 352 TIOCM_ST        Secondary TXD (transmit)
 353 TIOCM_SR        Secondary RXD (receive)
 354 TIOCM_CTS       CTS (clear to send)
 355 TIOCM_CAR       DCD (data carrier detect)
 356 TIOCM_CD        see TIOCM_CAR
 357 TIOCM_RNG       RNG (ring)
 358 TIOCM_RI        see TIOCM_RNG
 359 TIOCM_DSR       DSR (data set ready)
 360
 361 http://man7.org/linux/man-pages/man4/tty_ioctl.4.html
 362 */
 363
 364 int RS232_IsDCDEnabled(int comport_number)
 365 {
 366   int status;
 367
 368   ioctl(Cport[comport_number], TIOCMGET, &status);
 369
 370   if(status&TIOCM_CAR) return(1);
 371   else return(0);
 372 }
 373
 374
 375 int RS232_IsRINGEnabled(int comport_number)
 376 {
 377   int status;
 378
 379   ioctl(Cport[comport_number], TIOCMGET, &status);
 380
 381   if(status&TIOCM_RNG) return(1);
 382   else return(0);
 383 }
 384
 385
 386 int RS232_IsCTSEnabled(int comport_number)
 387 {
 388   int status;
 389
 390   ioctl(Cport[comport_number], TIOCMGET, &status);
 391
 392   if(status&TIOCM_CTS) return(1);
 393   else return(0);
 394 }
 395
 396
 397 int RS232_IsDSREnabled(int comport_number)
 398 {
 399   int status;
 400
 401   ioctl(Cport[comport_number], TIOCMGET, &status);
 402
 403   if(status&TIOCM_DSR) return(1);
 404   else return(0);
 405 }
 406
 407
 408 void RS232_enableDTR(int comport_number)
 409 {
 410   int status;
 411
 412   if(ioctl(Cport[comport_number], TIOCMGET, &status) == -1)
 413   {
 414     perror("unable to get portstatus");
 415   }
 416
 417   status |= TIOCM_DTR;    /* turn on DTR */
 418
 419   if(ioctl(Cport[comport_number], TIOCMSET, &status) == -1)
 420   {
 421     perror("unable to set portstatus");
 422   }
 423 }
 424
 425
 426 void RS232_disableDTR(int comport_number)
 427 {
 428   int status;
 429
 430   if(ioctl(Cport[comport_number], TIOCMGET, &status) == -1)
 431   {
 432     perror("unable to get portstatus");
 433   }
 434
 435   status &= ~TIOCM_DTR;    /* turn off DTR */
 436
 437   if(ioctl(Cport[comport_number], TIOCMSET, &status) == -1)
 438   {
 439     perror("unable to set portstatus");
 440   }
 441 }
 442
 443
 444 void RS232_enableRTS(int comport_number)
 445 {
 446   int status;
 447
 448   if(ioctl(Cport[comport_number], TIOCMGET, &status) == -1)
 449   {
 450     perror("unable to get portstatus");
 451   }
 452
 453   status |= TIOCM_RTS;    /* turn on RTS */
 454
 455   if(ioctl(Cport[comport_number], TIOCMSET, &status) == -1)
 456   {
 457     perror("unable to set portstatus");
 458   }
 459 }
 460
 461
 462 void RS232_disableRTS(int comport_number)
 463 {
 464   int status;
 465
 466   if(ioctl(Cport[comport_number], TIOCMGET, &status) == -1)
 467   {
 468     perror("unable to get portstatus");
 469   }
 470
 471   status &= ~TIOCM_RTS;    /* turn off RTS */
 472
 473   if(ioctl(Cport[comport_number], TIOCMSET, &status) == -1)
 474   {
 475     perror("unable to set portstatus");
 476   }
 477 }
 478
 479
 480 void RS232_flushRX(int comport_number)
 481 {
 482   tcflush(Cport[comport_number], TCIFLUSH);
 483 }
 484
 485
 486 void RS232_flushTX(int comport_number)
 487 {
 488   tcflush(Cport[comport_number], TCOFLUSH);
 489 }
 490
 491
 492 void RS232_flushRXTX(int comport_number)
 493 {
 494   tcflush(Cport[comport_number], TCIOFLUSH);
 495 }
 496
 497
 498 #else  /* windows */
 499
 500 #define RS232_PORTNR  32
 501
 502 HANDLE Cport[RS232_PORTNR];
 503
 504
 505 char *comports[RS232_PORTNR]={"\\\\.\\COM1",  "\\\\.\\COM2",  "\\\\.\\COM3",  "\\\\.\\COM4",
 506                               "\\\\.\\COM5",  "\\\\.\\COM6",  "\\\\.\\COM7",  "\\\\.\\COM8",
 507                               "\\\\.\\COM9",  "\\\\.\\COM10", "\\\\.\\COM11", "\\\\.\\COM12",
 508                               "\\\\.\\COM13", "\\\\.\\COM14", "\\\\.\\COM15", "\\\\.\\COM16",
 509                               "\\\\.\\COM17", "\\\\.\\COM18", "\\\\.\\COM19", "\\\\.\\COM20",
 510                               "\\\\.\\COM21", "\\\\.\\COM22", "\\\\.\\COM23", "\\\\.\\COM24",
 511                               "\\\\.\\COM25", "\\\\.\\COM26", "\\\\.\\COM27", "\\\\.\\COM28",
 512                               "\\\\.\\COM29", "\\\\.\\COM30", "\\\\.\\COM31", "\\\\.\\COM32"};
 513
 514 char mode_str[128];
 515
 516
 517 int RS232_OpenComport(int comport_number, int baudrate, const char *mode, int flowctrl)
 518 {
 519   if((comport_number>=RS232_PORTNR)||(comport_number<0))
 520   {
 521     printf("illegal comport number\n");
 522     return(1);
 523   }
 524
 525   switch(baudrate)
 526   {
 527     case     110 : strcpy(mode_str, "baud=110");
 528                    break;
 529     case     300 : strcpy(mode_str, "baud=300");
 530                    break;
 531     case     600 : strcpy(mode_str, "baud=600");
 532                    break;
 533     case    1200 : strcpy(mode_str, "baud=1200");
 534                    break;
 535     case    2400 : strcpy(mode_str, "baud=2400");
 536                    break;
 537     case    4800 : strcpy(mode_str, "baud=4800");
 538                    break;
 539     case    9600 : strcpy(mode_str, "baud=9600");
 540                    break;
 541     case   19200 : strcpy(mode_str, "baud=19200");
 542                    break;
 543     case   38400 : strcpy(mode_str, "baud=38400");
 544                    break;
 545     case   57600 : strcpy(mode_str, "baud=57600");
 546                    break;
 547     case  115200 : strcpy(mode_str, "baud=115200");
 548                    break;
 549     case  128000 : strcpy(mode_str, "baud=128000");
 550                    break;
 551     case  256000 : strcpy(mode_str, "baud=256000");
 552                    break;
 553     case  500000 : strcpy(mode_str, "baud=500000");
 554                    break;
 555     case  921600 : strcpy(mode_str, "baud=921600");
 556                    break;
 557     case 1000000 : strcpy(mode_str, "baud=1000000");
 558                    break;
 559     case 1500000 : strcpy(mode_str, "baud=1500000");
 560                    break;
 561     case 2000000 : strcpy(mode_str, "baud=2000000");
 562                    break;
 563     case 3000000 : strcpy(mode_str, "baud=3000000");
 564                    break;
 565     default      : printf("invalid baudrate\n");
 566                    return(1);
 567                    break;
 568   }
 569
 570   if(strlen(mode) != 3)
 571   {
 572     printf("invalid mode \"%s\"\n", mode);
 573     return(1);
 574   }
 575
 576   switch(mode[0])
 577   {
 578     case '8': strcat(mode_str, " data=8");
 579               break;
 580     case '7': strcat(mode_str, " data=7");
 581               break;
 582     case '6': strcat(mode_str, " data=6");
 583               break;
 584     case '5': strcat(mode_str, " data=5");
 585               break;
 586     default : printf("invalid number of data-bits '%c'\n", mode[0]);
 587               return(1);
 588               break;
 589   }
 590
 591   switch(mode[1])
 592   {
 593     case 'N':
 594     case 'n': strcat(mode_str, " parity=n");
 595               break;
 596     case 'E':
 597     case 'e': strcat(mode_str, " parity=e");
 598               break;
 599     case 'O':
 600     case 'o': strcat(mode_str, " parity=o");
 601               break;
 602     default : printf("invalid parity '%c'\n", mode[1]);
 603               return(1);
 604               break;
 605   }
 606
 607   switch(mode[2])
 608   {
 609     case '1': strcat(mode_str, " stop=1");
 610               break;
 611     case '2': strcat(mode_str, " stop=2");
 612               break;
 613     default : printf("invalid number of stop bits '%c'\n", mode[2]);
 614               return(1);
 615               break;
 616   }
 617
 618   if(flowctrl)
 619   {
 620     strcat(mode_str, " xon=off to=off odsr=off dtr=on rts=off");
 621   }
 622   else
 623   {
 624     strcat(mode_str, " xon=off to=off odsr=off dtr=on rts=on");
 625   }
 626
 627 /*
 628 http://msdn.microsoft.com/en-us/library/windows/desktop/aa363145%28v=vs.85%29.aspx
 629
 630 http://technet.microsoft.com/en-us/library/cc732236.aspx
 631
 632 https://docs.microsoft.com/en-us/windows/desktop/api/winbase/ns-winbase-_dcb
 633 */
 634
 635   Cport[comport_number] = CreateFileA(comports[comport_number],
 636                       GENERIC_READ|GENERIC_WRITE,
 637                       0,                          /* no share  */
 638                       NULL,                       /* no security */
 639                       OPEN_EXISTING,
 640                       0,                          /* no threads */
 641                       NULL);                      /* no templates */
 642
 643   if(Cport[comport_number]==INVALID_HANDLE_VALUE)
 644   {
 645     printf("unable to open comport\n");
 646     return(1);
 647   }
 648
 649   DCB port_settings;
 650   memset(&port_settings, 0, sizeof(port_settings));  /* clear the new struct  */
 651   port_settings.DCBlength = sizeof(port_settings);
 652
 653   if(!BuildCommDCBA(mode_str, &port_settings))
 654   {
 655     printf("unable to set comport dcb settings\n");
 656     CloseHandle(Cport[comport_number]);
 657     return(1);
 658   }
 659
 660   if(flowctrl)
 661   {
 662     port_settings.fOutxCtsFlow = TRUE;
 663     port_settings.fRtsControl = RTS_CONTROL_HANDSHAKE;
 664   }
 665
 666   if(!SetCommState(Cport[comport_number], &port_settings))
 667   {
 668     printf("unable to set comport cfg settings\n");
 669     CloseHandle(Cport[comport_number]);
 670     return(1);
 671   }
 672
 673   COMMTIMEOUTS Cptimeouts;
 674
 675   Cptimeouts.ReadIntervalTimeout         = MAXDWORD;
 676   Cptimeouts.ReadTotalTimeoutMultiplier  = 0;
 677   Cptimeouts.ReadTotalTimeoutConstant    = 0;
 678   Cptimeouts.WriteTotalTimeoutMultiplier = 0;
 679   Cptimeouts.WriteTotalTimeoutConstant   = 0;
 680
 681   if(!SetCommTimeouts(Cport[comport_number], &Cptimeouts))
 682   {
 683     printf("unable to set comport time-out settings\n");
 684     CloseHandle(Cport[comport_number]);
 685     return(1);
 686   }
 687
 688   return(0);
 689 }
 690
 691
 692 int RS232_PollComport(int comport_number, unsigned char *buf, int size)
 693 {
 694   int n;
 695
 696 /* added the void pointer cast, otherwise gcc will complain about */
 697 /* "warning: dereferencing type-punned pointer will break strict aliasing rules" */
 698
 699   ReadFile(Cport[comport_number], buf, size, (LPDWORD)((void *)&n), NULL);
 700
 701   return(n);
 702 }
 703
 704
 705 int RS232_SendByte(int comport_number, unsigned char byte)
 706 {
 707   int n;
 708
 709   WriteFile(Cport[comport_number], &byte, 1, (LPDWORD)((void *)&n), NULL);
 710
 711   if(n<0)  return(1);
 712
 713   return(0);
 714 }
 715
 716
 717 int RS232_SendBuf(int comport_number, unsigned char *buf, int size)
 718 {
 719   int n;
 720
 721   if(WriteFile(Cport[comport_number], buf, size, (LPDWORD)((void *)&n), NULL))
 722   {
 723     return(n);
 724   }
 725
 726   return(-1);
 727 }
 728
 729
 730 void RS232_CloseComport(int comport_number)
 731 {
 732   CloseHandle(Cport[comport_number]);
 733 }
 734
 735 /*
 736 http://msdn.microsoft.com/en-us/library/windows/desktop/aa363258%28v=vs.85%29.aspx
 737 */
 738
 739 int RS232_IsDCDEnabled(int comport_number)
 740 {
 741   int status;
 742
 743   GetCommModemStatus(Cport[comport_number], (LPDWORD)((void *)&status));
 744
 745   if(status&MS_RLSD_ON) return(1);
 746   else return(0);
 747 }
 748
 749
 750 int RS232_IsRINGEnabled(int comport_number)
 751 {
 752   int status;
 753
 754   GetCommModemStatus(Cport[comport_number], (LPDWORD)((void *)&status));
 755
 756   if(status&MS_RING_ON) return(1);
 757   else return(0);
 758 }
 759
 760
 761 int RS232_IsCTSEnabled(int comport_number)
 762 {
 763   int status;
 764
 765   GetCommModemStatus(Cport[comport_number], (LPDWORD)((void *)&status));
 766
 767   if(status&MS_CTS_ON) return(1);
 768   else return(0);
 769 }
 770
 771
 772 int RS232_IsDSREnabled(int comport_number)
 773 {
 774   int status;
 775
 776   GetCommModemStatus(Cport[comport_number], (LPDWORD)((void *)&status));
 777
 778   if(status&MS_DSR_ON) return(1);
 779   else return(0);
 780 }
 781
 782
 783 void RS232_enableDTR(int comport_number)
 784 {
 785   EscapeCommFunction(Cport[comport_number], SETDTR);
 786 }
 787
 788
 789 void RS232_disableDTR(int comport_number)
 790 {
 791   EscapeCommFunction(Cport[comport_number], CLRDTR);
 792 }
 793
 794
 795 void RS232_enableRTS(int comport_number)
 796 {
 797   EscapeCommFunction(Cport[comport_number], SETRTS);
 798 }
 799
 800
 801 void RS232_disableRTS(int comport_number)
 802 {
 803   EscapeCommFunction(Cport[comport_number], CLRRTS);
 804 }
 805
 806 /*
 807 https://msdn.microsoft.com/en-us/library/windows/desktop/aa363428%28v=vs.85%29.aspx
 808 */
 809
 810 void RS232_flushRX(int comport_number)
 811 {
 812   PurgeComm(Cport[comport_number], PURGE_RXCLEAR | PURGE_RXABORT);
 813 }
 814
 815
 816 void RS232_flushTX(int comport_number)
 817 {
 818   PurgeComm(Cport[comport_number], PURGE_TXCLEAR | PURGE_TXABORT);
 819 }
 820
 821
 822 void RS232_flushRXTX(int comport_number)
 823 {
 824   PurgeComm(Cport[comport_number], PURGE_RXCLEAR | PURGE_RXABORT);
 825   PurgeComm(Cport[comport_number], PURGE_TXCLEAR | PURGE_TXABORT);
 826 }
 827
 828
 829 #endif
 830
 831
 832 void RS232_cputs(int comport_number, const char *text)  /* sends a string to serial port */
 833 {
 834   while(*text != 0)   RS232_SendByte(comport_number, *(text++));
 835 }
 836
 837
 838 /* return index in comports matching to device name or -1 if not found */
 839 int RS232_GetPortnr(const char *devname)
 840 {
 841   int i;
 842
 843   char str[32];
 844
 845 #if defined(__linux__) || defined(__FreeBSD__)   /* Linux & FreeBSD */
 846   strcpy(str, "/dev/");
 847 #else  /* windows */
 848   strcpy(str, "\\\\.\\");
 849 #endif
 850   strncat(str, devname, 16);
 851   str[31] = 0;
 852
 853   for(i=0; i<RS232_PORTNR; i++)
 854   {
 855     if(!strcmp(comports[i], str))
 856     {
 857       return i;
 858     }
 859   }
 860
 861   return -1;  /* device not found */
 862 }
 863
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