1 /* $NetBSD: refclock_arbiter.c,v 1.1.1.2 2012/01/31 21:26:42 kardel Exp $ */ 2 3 /* 4 * refclock_arbiter - clock driver for Arbiter 1088A/B Satellite 5 * Controlled Clock 6 */ 7 8 #ifdef HAVE_CONFIG_H 9 #include <config.h> 10 #endif 11 12 #if defined(REFCLOCK) && defined(CLOCK_ARBITER) 13 14 #include "ntpd.h" 15 #include "ntp_io.h" 16 #include "ntp_refclock.h" 17 #include "ntp_stdlib.h" 18 19 #include <stdio.h> 20 #include <ctype.h> 21 22 #ifdef SYS_WINNT 23 extern int async_write(int, const void *, unsigned int); 24 #undef write 25 #define write(fd, data, octets) async_write(fd, data, octets) 26 #endif 27 28 /* 29 * This driver supports the Arbiter 1088A/B Satellite Controlled Clock. 30 * The claimed accuracy of this clock is 100 ns relative to the PPS 31 * output when receiving four or more satellites. 32 * 33 * The receiver should be configured before starting the NTP daemon, in 34 * order to establish reliable position and operating conditions. It 35 * does not initiate surveying or hold mode. For use with NTP, the 36 * daylight savings time feature should be disables (D0 command) and the 37 * broadcast mode set to operate in UTC (BU command). 38 * 39 * The timecode format supported by this driver is selected by the poll 40 * sequence "B5", which initiates a line in the following format to be 41 * repeated once per second until turned off by the "B0" poll sequence. 42 * 43 * Format B5 (24 ASCII printing characters): 44 * 45 * <cr><lf>i yy ddd hh:mm:ss.000bbb 46 * 47 * on-time = <cr> 48 * i = synchronization flag (' ' = locked, '?' = unlocked) 49 * yy = year of century 50 * ddd = day of year 51 * hh:mm:ss = hours, minutes, seconds 52 * .000 = fraction of second (not used) 53 * bbb = tailing spaces for fill 54 * 55 * The alarm condition is indicated by a '?' at i, which indicates the 56 * receiver is not synchronized. In normal operation, a line consisting 57 * of the timecode followed by the time quality character (TQ) followed 58 * by the receiver status string (SR) is written to the clockstats file. 59 * The time quality character is encoded in IEEE P1344 standard: 60 * 61 * Format TQ (IEEE P1344 estimated worst-case time quality) 62 * 63 * 0 clock locked, maximum accuracy 64 * F clock failure, time not reliable 65 * 4 clock unlocked, accuracy < 1 us 66 * 5 clock unlocked, accuracy < 10 us 67 * 6 clock unlocked, accuracy < 100 us 68 * 7 clock unlocked, accuracy < 1 ms 69 * 8 clock unlocked, accuracy < 10 ms 70 * 9 clock unlocked, accuracy < 100 ms 71 * A clock unlocked, accuracy < 1 s 72 * B clock unlocked, accuracy < 10 s 73 * 74 * The status string is encoded as follows: 75 * 76 * Format SR (25 ASCII printing characters) 77 * 78 * V=vv S=ss T=t P=pdop E=ee 79 * 80 * vv = satellites visible 81 * ss = relative signal strength 82 * t = satellites tracked 83 * pdop = position dilution of precision (meters) 84 * ee = hardware errors 85 * 86 * If flag4 is set, an additional line consisting of the receiver 87 * latitude (LA), longitude (LO), elevation (LH) (meters), and data 88 * buffer (DB) is written to this file. If channel B is enabled for 89 * deviation mode and connected to a 1-PPS signal, the last two numbers 90 * on the line are the deviation and standard deviation averaged over 91 * the last 15 seconds. 92 * 93 * PPS calibration fudge time1 .001240 94 */ 95 96 /* 97 * Interface definitions 98 */ 99 #define DEVICE "/dev/gps%d" /* device name and unit */ 100 #define SPEED232 B9600 /* uart speed (9600 baud) */ 101 #define PRECISION (-20) /* precision assumed (about 1 us) */ 102 #define REFID "GPS " /* reference ID */ 103 #define DESCRIPTION "Arbiter 1088A/B GPS Receiver" /* WRU */ 104 #define LENARB 24 /* format B5 timecode length */ 105 #define MAXSTA 40 /* max length of status string */ 106 #define MAXPOS 80 /* max length of position string */ 107 108 #ifdef PRE_NTP420 109 #define MODE ttlmax 110 #else 111 #define MODE ttl 112 #endif 113 114 #define COMMAND_HALT_BCAST ( (peer->MODE % 2) ? "O0" : "B0" ) 115 #define COMMAND_START_BCAST ( (peer->MODE % 2) ? "O5" : "B5" ) 116 117 /* 118 * ARB unit control structure 119 */ 120 struct arbunit { 121 l_fp laststamp; /* last receive timestamp */ 122 int tcswitch; /* timecode switch/counter */ 123 char qualchar; /* IEEE P1344 quality (TQ command) */ 124 char status[MAXSTA]; /* receiver status (SR command) */ 125 char latlon[MAXPOS]; /* receiver position (lat/lon/alt) */ 126 }; 127 128 /* 129 * Function prototypes 130 */ 131 static int arb_start (int, struct peer *); 132 static void arb_shutdown (int, struct peer *); 133 static void arb_receive (struct recvbuf *); 134 static void arb_poll (int, struct peer *); 135 136 /* 137 * Transfer vector 138 */ 139 struct refclock refclock_arbiter = { 140 arb_start, /* start up driver */ 141 arb_shutdown, /* shut down driver */ 142 arb_poll, /* transmit poll message */ 143 noentry, /* not used (old arb_control) */ 144 noentry, /* initialize driver (not used) */ 145 noentry, /* not used (old arb_buginfo) */ 146 NOFLAGS /* not used */ 147 }; 148 149 150 /* 151 * arb_start - open the devices and initialize data for processing 152 */ 153 static int 154 arb_start( 155 int unit, 156 struct peer *peer 157 ) 158 { 159 register struct arbunit *up; 160 struct refclockproc *pp; 161 int fd; 162 char device[20]; 163 164 /* 165 * Open serial port. Use CLK line discipline, if available. 166 */ 167 snprintf(device, sizeof(device), DEVICE, unit); 168 if (!(fd = refclock_open(device, SPEED232, LDISC_CLK))) 169 return (0); 170 171 /* 172 * Allocate and initialize unit structure 173 */ 174 up = emalloc(sizeof(*up)); 175 memset(up, 0, sizeof(*up)); 176 pp = peer->procptr; 177 pp->io.clock_recv = arb_receive; 178 pp->io.srcclock = (caddr_t)peer; 179 pp->io.datalen = 0; 180 pp->io.fd = fd; 181 if (!io_addclock(&pp->io)) { 182 close(fd); 183 pp->io.fd = -1; 184 free(up); 185 return (0); 186 } 187 pp->unitptr = (caddr_t)up; 188 189 /* 190 * Initialize miscellaneous variables 191 */ 192 peer->precision = PRECISION; 193 pp->clockdesc = DESCRIPTION; 194 memcpy((char *)&pp->refid, REFID, 4); 195 if (peer->MODE > 1) { 196 msyslog(LOG_NOTICE, "ARBITER: Invalid mode %d", peer->MODE); 197 close(fd); 198 pp->io.fd = -1; 199 free(up); 200 return (0); 201 } 202 #ifdef DEBUG 203 if(debug) { printf("arbiter: mode = %d.\n", peer->MODE); } 204 #endif 205 write(pp->io.fd, COMMAND_HALT_BCAST, 2); 206 return (1); 207 } 208 209 210 /* 211 * arb_shutdown - shut down the clock 212 */ 213 static void 214 arb_shutdown( 215 int unit, 216 struct peer *peer 217 ) 218 { 219 register struct arbunit *up; 220 struct refclockproc *pp; 221 222 pp = peer->procptr; 223 up = (struct arbunit *)pp->unitptr; 224 if (-1 != pp->io.fd) 225 io_closeclock(&pp->io); 226 if (NULL != up) 227 free(up); 228 } 229 230 231 /* 232 * arb_receive - receive data from the serial interface 233 */ 234 static void 235 arb_receive( 236 struct recvbuf *rbufp 237 ) 238 { 239 register struct arbunit *up; 240 struct refclockproc *pp; 241 struct peer *peer; 242 l_fp trtmp; 243 int temp; 244 u_char syncchar; /* synch indicator */ 245 char tbuf[BMAX]; /* temp buffer */ 246 247 /* 248 * Initialize pointers and read the timecode and timestamp 249 */ 250 peer = (struct peer *)rbufp->recv_srcclock; 251 pp = peer->procptr; 252 up = (struct arbunit *)pp->unitptr; 253 temp = refclock_gtlin(rbufp, tbuf, BMAX, &trtmp); 254 255 /* 256 * Note we get a buffer and timestamp for both a <cr> and <lf>, 257 * but only the <cr> timestamp is retained. The program first 258 * sends a TQ and expects the echo followed by the time quality 259 * character. It then sends a B5 starting the timecode broadcast 260 * and expects the echo followed some time later by the on-time 261 * character <cr> and then the <lf> beginning the timecode 262 * itself. Finally, at the <cr> beginning the next timecode at 263 * the next second, the program sends a B0 shutting down the 264 * timecode broadcast. 265 * 266 * If flag4 is set, the program snatches the latitude, longitude 267 * and elevation and writes it to the clockstats file. 268 */ 269 if (temp == 0) 270 return; 271 272 pp->lastrec = up->laststamp; 273 up->laststamp = trtmp; 274 if (temp < 3) 275 return; 276 277 if (up->tcswitch == 0) { 278 279 /* 280 * Collect statistics. If nothing is recogized, just 281 * ignore; sometimes the clock doesn't stop spewing 282 * timecodes for awhile after the B0 command. 283 * 284 * If flag4 is not set, send TQ, SR, B5. If flag4 is 285 * sset, send TQ, SR, LA, LO, LH, DB, B5. When the 286 * median filter is full, send B0. 287 */ 288 if (!strncmp(tbuf, "TQ", 2)) { 289 up->qualchar = tbuf[2]; 290 write(pp->io.fd, "SR", 2); 291 return; 292 293 } else if (!strncmp(tbuf, "SR", 2)) { 294 strcpy(up->status, tbuf + 2); 295 if (pp->sloppyclockflag & CLK_FLAG4) 296 write(pp->io.fd, "LA", 2); 297 else 298 write(pp->io.fd, COMMAND_START_BCAST, 2); 299 return; 300 301 } else if (!strncmp(tbuf, "LA", 2)) { 302 strcpy(up->latlon, tbuf + 2); 303 write(pp->io.fd, "LO", 2); 304 return; 305 306 } else if (!strncmp(tbuf, "LO", 2)) { 307 strcat(up->latlon, " "); 308 strcat(up->latlon, tbuf + 2); 309 write(pp->io.fd, "LH", 2); 310 return; 311 312 } else if (!strncmp(tbuf, "LH", 2)) { 313 strcat(up->latlon, " "); 314 strcat(up->latlon, tbuf + 2); 315 write(pp->io.fd, "DB", 2); 316 return; 317 318 } else if (!strncmp(tbuf, "DB", 2)) { 319 strcat(up->latlon, " "); 320 strcat(up->latlon, tbuf + 2); 321 record_clock_stats(&peer->srcadr, up->latlon); 322 #ifdef DEBUG 323 if (debug) 324 printf("arbiter: %s\n", up->latlon); 325 #endif 326 write(pp->io.fd, COMMAND_START_BCAST, 2); 327 } 328 } 329 330 /* 331 * We get down to business, check the timecode format and decode 332 * its contents. If the timecode has valid length, but not in 333 * proper format, we declare bad format and exit. If the 334 * timecode has invalid length, which sometimes occurs when the 335 * B0 amputates the broadcast, we just quietly steal away. Note 336 * that the time quality character and receiver status string is 337 * tacked on the end for clockstats display. 338 */ 339 up->tcswitch++; 340 if (up->tcswitch <= 1 || temp < LENARB) 341 return; 342 343 /* 344 * Timecode format B5: "i yy ddd hh:mm:ss.000 " 345 */ 346 strncpy(pp->a_lastcode, tbuf, BMAX); 347 pp->a_lastcode[LENARB - 2] = up->qualchar; 348 strcat(pp->a_lastcode, up->status); 349 pp->lencode = strlen(pp->a_lastcode); 350 syncchar = ' '; 351 if (sscanf(pp->a_lastcode, "%c%2d %3d %2d:%2d:%2d", 352 &syncchar, &pp->year, &pp->day, &pp->hour, 353 &pp->minute, &pp->second) != 6) { 354 refclock_report(peer, CEVNT_BADREPLY); 355 write(pp->io.fd, COMMAND_HALT_BCAST, 2); 356 return; 357 } 358 359 /* 360 * We decode the clock dispersion from the time quality 361 * character. 362 */ 363 switch (up->qualchar) { 364 365 case '0': /* locked, max accuracy */ 366 pp->disp = 1e-7; 367 pp->lastref = pp->lastrec; 368 break; 369 370 case '4': /* unlock accuracy < 1 us */ 371 pp->disp = 1e-6; 372 break; 373 374 case '5': /* unlock accuracy < 10 us */ 375 pp->disp = 1e-5; 376 break; 377 378 case '6': /* unlock accuracy < 100 us */ 379 pp->disp = 1e-4; 380 break; 381 382 case '7': /* unlock accuracy < 1 ms */ 383 pp->disp = .001; 384 break; 385 386 case '8': /* unlock accuracy < 10 ms */ 387 pp->disp = .01; 388 break; 389 390 case '9': /* unlock accuracy < 100 ms */ 391 pp->disp = .1; 392 break; 393 394 case 'A': /* unlock accuracy < 1 s */ 395 pp->disp = 1; 396 break; 397 398 case 'B': /* unlock accuracy < 10 s */ 399 pp->disp = 10; 400 break; 401 402 case 'F': /* clock failure */ 403 pp->disp = MAXDISPERSE; 404 refclock_report(peer, CEVNT_FAULT); 405 write(pp->io.fd, COMMAND_HALT_BCAST, 2); 406 return; 407 408 default: 409 pp->disp = MAXDISPERSE; 410 refclock_report(peer, CEVNT_BADREPLY); 411 write(pp->io.fd, COMMAND_HALT_BCAST, 2); 412 return; 413 } 414 if (syncchar != ' ') 415 pp->leap = LEAP_NOTINSYNC; 416 else 417 pp->leap = LEAP_NOWARNING; 418 419 /* 420 * Process the new sample in the median filter and determine the 421 * timecode timestamp. 422 */ 423 if (!refclock_process(pp)) 424 refclock_report(peer, CEVNT_BADTIME); 425 else if (peer->disp > MAXDISTANCE) 426 refclock_receive(peer); 427 428 /* if (up->tcswitch >= MAXSTAGE) { */ 429 write(pp->io.fd, COMMAND_HALT_BCAST, 2); 430 /* } */ 431 } 432 433 434 /* 435 * arb_poll - called by the transmit procedure 436 */ 437 static void 438 arb_poll( 439 int unit, 440 struct peer *peer 441 ) 442 { 443 register struct arbunit *up; 444 struct refclockproc *pp; 445 446 /* 447 * Time to poll the clock. The Arbiter clock responds to a "B5" 448 * by returning a timecode in the format specified above. 449 * Transmission occurs once per second, unless turned off by a 450 * "B0". Note there is no checking on state, since this may not 451 * be the only customer reading the clock. Only one customer 452 * need poll the clock; all others just listen in. 453 */ 454 pp = peer->procptr; 455 up = (struct arbunit *)pp->unitptr; 456 pp->polls++; 457 up->tcswitch = 0; 458 if (write(pp->io.fd, "TQ", 2) != 2) 459 refclock_report(peer, CEVNT_FAULT); 460 461 /* 462 * Process median filter samples. If none received, declare a 463 * timeout and keep going. 464 */ 465 if (pp->coderecv == pp->codeproc) { 466 refclock_report(peer, CEVNT_TIMEOUT); 467 return; 468 } 469 refclock_receive(peer); 470 record_clock_stats(&peer->srcadr, pp->a_lastcode); 471 #ifdef DEBUG 472 if (debug) 473 printf("arbiter: timecode %d %s\n", 474 pp->lencode, pp->a_lastcode); 475 #endif 476 } 477 478 #else 479 int refclock_arbiter_bs; 480 #endif /* REFCLOCK */ 481