1 /* 2 * refclock_heath - clock driver for Heath GC-1000 3 * (but no longer the GC-1001 Model II, which apparently never worked) 4 */ 5 6 #ifdef HAVE_CONFIG_H 7 # include <config.h> 8 #endif 9 10 #if defined(REFCLOCK) && defined(CLOCK_HEATH) 11 12 #include "ntpd.h" 13 #include "ntp_io.h" 14 #include "ntp_refclock.h" 15 #include "ntp_stdlib.h" 16 17 #include <stdio.h> 18 #include <ctype.h> 19 20 #ifdef HAVE_SYS_IOCTL_H 21 # include <sys/ioctl.h> 22 #endif /* not HAVE_SYS_IOCTL_H */ 23 24 /* 25 * This driver supports the Heath GC-1000 Most Accurate Clock, with 26 * RS232C Output Accessory. This is a WWV/WWVH receiver somewhat less 27 * robust than other supported receivers. Its claimed accuracy is 100 ms 28 * when actually synchronized to the broadcast signal, but this doesn't 29 * happen even most of the time, due to propagation conditions, ambient 30 * noise sources, etc. When not synchronized, the accuracy is at the 31 * whim of the internal clock oscillator, which can wander into the 32 * sunset without warning. Since the indicated precision is 100 ms, 33 * expect a host synchronized only to this thing to wander to and fro, 34 * occasionally being rudely stepped when the offset exceeds the default 35 * clock_max of 128 ms. 36 * 37 * There were two GC-1000 versions supported by this driver. The original 38 * GC-1000 with RS-232 output first appeared in 1983, but dissapeared 39 * from the market a few years later. The GC-1001 II with RS-232 output 40 * first appeared circa 1990, but apparently is no longer manufactured. 41 * The two models differ considerably, both in interface and commands. 42 * The GC-1000 has a pseudo-bipolar timecode output triggered by a RTS 43 * transition. The timecode includes both the day of year and time of 44 * day. The GC-1001 II has a true bipolar output and a complement of 45 * single character commands. The timecode includes only the time of 46 * day. 47 * 48 * The GC-1001 II was apparently never tested and, based on a Coverity 49 * scan, apparently never worked [Bug 689]. Related code has been disabled. 50 * 51 * GC-1000 52 * 53 * The internal DIPswitches should be set to operate in MANUAL mode. The 54 * external DIPswitches should be set to GMT and 24-hour format. 55 * 56 * In MANUAL mode the clock responds to a rising edge of the request to 57 * send (RTS) modem control line by sending the timecode. Therefore, it 58 * is necessary that the operating system implement the TIOCMBIC and 59 * TIOCMBIS ioctl system calls and TIOCM_RTS control bit. Present 60 * restrictions require the use of a POSIX-compatible programming 61 * interface, although other interfaces may work as well. 62 * 63 * A simple hardware modification to the clock can be made which 64 * prevents the clock hearing the request to send (RTS) if the HI SPEC 65 * lamp is out. Route the HISPEC signal to the tone decoder board pin 66 * 19, from the display, pin 19. Isolate pin 19 of the decoder board 67 * first, but maintain connection with pin 10. Also isolate pin 38 of 68 * the CPU on the tone board, and use half an added 7400 to gate the 69 * original signal to pin 38 with that from pin 19. 70 * 71 * The clock message consists of 23 ASCII printing characters in the 72 * following format: 73 * 74 * hh:mm:ss.f AM dd/mm/yr<cr> 75 * 76 * hh:mm:ss.f = hours, minutes, seconds 77 * f = deciseconds ('?' when out of spec) 78 * AM/PM/bb = blank in 24-hour mode 79 * dd/mm/yr = day, month, year 80 * 81 * The alarm condition is indicated by '?', rather than a digit, at f. 82 * Note that 0?:??:??.? is displayed before synchronization is first 83 * established and hh:mm:ss.? once synchronization is established and 84 * then lost again for about a day. 85 * 86 * GC-1001 II 87 * 88 * Commands consist of a single letter and are case sensitive. When 89 * enterred in lower case, a description of the action performed is 90 * displayed. When enterred in upper case the action is performed. 91 * Following is a summary of descriptions as displayed by the clock: 92 * 93 * The clock responds with a command The 'A' command returns an ASCII 94 * local time string: HH:MM:SS.T xx<CR>, where 95 * 96 * HH = hours 97 * MM = minutes 98 * SS = seconds 99 * T = tenths-of-seconds 100 * xx = 'AM', 'PM', or ' ' 101 * <CR> = carriage return 102 * 103 * The 'D' command returns 24 pairs of bytes containing the variable 104 * divisor value at the end of each of the previous 24 hours. This 105 * allows the timebase trimming process to be observed. UTC hour 00 is 106 * always returned first. The first byte of each pair is the high byte 107 * of (variable divisor * 16); the second byte is the low byte of 108 * (variable divisor * 16). For example, the byte pair 3C 10 would be 109 * returned for a divisor of 03C1 hex (961 decimal). 110 * 111 * The 'I' command returns: | TH | TL | ER | DH | DL | U1 | I1 | I2 | , 112 * where 113 * 114 * TH = minutes since timebase last trimmed (high byte) 115 * TL = minutes since timebase last trimmed (low byte) 116 * ER = last accumulated error in 1.25 ms increments 117 * DH = high byte of (current variable divisor * 16) 118 * DL = low byte of (current variable divisor * 16) 119 * U1 = UT1 offset (/.1 s): | + | 4 | 2 | 1 | 0 | 0 | 0 | 0 | 120 * I1 = information byte 1: | W | C | D | I | U | T | Z | 1 | , 121 * where 122 * 123 * W = set by WWV(H) 124 * C = CAPTURE LED on 125 * D = TRIM DN LED on 126 * I = HI SPEC LED on 127 * U = TRIM UP LED on 128 * T = DST switch on 129 * Z = UTC switch on 130 * 1 = UT1 switch on 131 * 132 * I2 = information byte 2: | 8 | 8 | 4 | 2 | 1 | D | d | S | , 133 * where 134 * 135 * 8, 8, 4, 2, 1 = TIME ZONE switch settings 136 * D = DST bit (#55) in last-received frame 137 * d = DST bit (#2) in last-received frame 138 * S = clock is in simulation mode 139 * 140 * The 'P' command returns 24 bytes containing the number of frames 141 * received without error during UTC hours 00 through 23, providing an 142 * indication of hourly propagation. These bytes are updated each hour 143 * to reflect the previous 24 hour period. UTC hour 00 is always 144 * returned first. 145 * 146 * The 'T' command returns the UTC time: | HH | MM | SS | T0 | , where 147 * HH = tens-of-hours and hours (packed BCD) 148 * MM = tens-of-minutes and minutes (packed BCD) 149 * SS = tens-of-seconds and seconds (packed BCD) 150 * T = tenths-of-seconds (BCD) 151 * 152 * Fudge Factors 153 * 154 * A fudge time1 value of .04 s appears to center the clock offset 155 * residuals. The fudge time2 parameter is the local time offset east of 156 * Greenwich, which depends on DST. Sorry about that, but the clock 157 * gives no hint on what the DIPswitches say. 158 */ 159 160 /* 161 * Interface definitions 162 */ 163 #define DEVICE "/dev/heath%d" /* device name and unit */ 164 #define PRECISION (-4) /* precision assumed (about 100 ms) */ 165 #define REFID "WWV\0" /* reference ID */ 166 #define DESCRIPTION "Heath GC-1000 Most Accurate Clock" /* WRU */ 167 168 #define LENHEATH1 23 /* min timecode length */ 169 #if 0 /* BUG 689 */ 170 #define LENHEATH2 13 /* min timecode length */ 171 #endif 172 173 /* 174 * Tables to compute the ddd of year form icky dd/mm timecode. Viva la 175 * leap. 176 */ 177 static int day1tab[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; 178 static int day2tab[] = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; 179 180 /* 181 * Baud rate table. The GC-1000 supports 1200, 2400 and 4800; the 182 * GC-1001 II supports only 9600. 183 */ 184 static int speed[] = {B1200, B2400, B4800, B9600}; 185 186 /* 187 * Function prototypes 188 */ 189 static int heath_start (int, struct peer *); 190 static void heath_shutdown (int, struct peer *); 191 static void heath_receive (struct recvbuf *); 192 static void heath_poll (int, struct peer *); 193 194 /* 195 * Transfer vector 196 */ 197 struct refclock refclock_heath = { 198 heath_start, /* start up driver */ 199 heath_shutdown, /* shut down driver */ 200 heath_poll, /* transmit poll message */ 201 noentry, /* not used (old heath_control) */ 202 noentry, /* initialize driver */ 203 noentry, /* not used (old heath_buginfo) */ 204 NOFLAGS /* not used */ 205 }; 206 207 208 /* 209 * heath_start - open the devices and initialize data for processing 210 */ 211 static int 212 heath_start( 213 int unit, 214 struct peer *peer 215 ) 216 { 217 struct refclockproc *pp; 218 int fd; 219 char device[20]; 220 221 /* 222 * Open serial port 223 */ 224 snprintf(device, sizeof(device), DEVICE, unit); 225 fd = refclock_open(&peer->srcadr, device, speed[peer->ttl & 0x3], 226 LDISC_REMOTE); 227 if (fd <= 0) 228 return (0); 229 pp = peer->procptr; 230 pp->io.clock_recv = heath_receive; 231 pp->io.srcclock = peer; 232 pp->io.datalen = 0; 233 pp->io.fd = fd; 234 if (!io_addclock(&pp->io)) { 235 close(fd); 236 pp->io.fd = -1; 237 return (0); 238 } 239 240 /* 241 * Initialize miscellaneous variables 242 */ 243 peer->precision = PRECISION; 244 pp->clockdesc = DESCRIPTION; 245 memcpy(&pp->refid, REFID, 4); 246 return (1); 247 } 248 249 250 /* 251 * heath_shutdown - shut down the clock 252 */ 253 static void 254 heath_shutdown( 255 int unit, 256 struct peer *peer 257 ) 258 { 259 struct refclockproc *pp; 260 261 pp = peer->procptr; 262 if (-1 != pp->io.fd) 263 io_closeclock(&pp->io); 264 } 265 266 267 /* 268 * heath_receive - receive data from the serial interface 269 */ 270 static void 271 heath_receive( 272 struct recvbuf *rbufp 273 ) 274 { 275 struct refclockproc *pp; 276 struct peer *peer; 277 l_fp trtmp; 278 int month, day; 279 int i; 280 char dsec, a[5]; 281 282 /* 283 * Initialize pointers and read the timecode and timestamp 284 */ 285 peer = rbufp->recv_peer; 286 pp = peer->procptr; 287 pp->lencode = refclock_gtlin(rbufp, pp->a_lastcode, BMAX, 288 &trtmp); 289 290 /* 291 * We get down to business, check the timecode format and decode 292 * its contents. If the timecode has invalid length or is not in 293 * proper format, we declare bad format and exit. 294 */ 295 switch (pp->lencode) { 296 297 /* 298 * GC-1000 timecode format: "hh:mm:ss.f AM mm/dd/yy" 299 * GC-1001 II timecode format: "hh:mm:ss.f " 300 */ 301 case LENHEATH1: 302 if (sscanf(pp->a_lastcode, 303 "%2d:%2d:%2d.%c%5c%2d/%2d/%2d", &pp->hour, 304 &pp->minute, &pp->second, &dsec, a, &month, &day, 305 &pp->year) != 8) { 306 refclock_report(peer, CEVNT_BADREPLY); 307 return; 308 } 309 break; 310 311 #if 0 /* BUG 689 */ 312 /* 313 * GC-1001 II timecode format: "hh:mm:ss.f " 314 */ 315 case LENHEATH2: 316 if (sscanf(pp->a_lastcode, "%2d:%2d:%2d.%c", &pp->hour, 317 &pp->minute, &pp->second, &dsec) != 4) { 318 refclock_report(peer, CEVNT_BADREPLY); 319 return; 320 } else { 321 struct tm *tm_time_p; 322 time_t now; 323 324 time(&now); /* we should grab 'now' earlier */ 325 tm_time_p = gmtime(&now); 326 /* 327 * There is a window of time around midnight 328 * where this will Do The Wrong Thing. 329 */ 330 if (tm_time_p) { 331 month = tm_time_p->tm_mon + 1; 332 day = tm_time_p->tm_mday; 333 } else { 334 refclock_report(peer, CEVNT_FAULT); 335 return; 336 } 337 } 338 break; 339 #endif 340 341 default: 342 refclock_report(peer, CEVNT_BADREPLY); 343 return; 344 } 345 346 /* 347 * We determine the day of the year from the DIPswitches. This 348 * should be fixed, since somebody might forget to set them. 349 * Someday this hazard will be fixed by a fiendish scheme that 350 * looks at the timecode and year the radio shows, then computes 351 * the residue of the seconds mod the seconds in a leap cycle. 352 * If in the third year of that cycle and the third and later 353 * months of that year, add one to the day. Then, correct the 354 * timecode accordingly. Icky pooh. This bit of nonsense could 355 * be avoided if the engineers had been required to write a 356 * device driver before finalizing the timecode format. 357 */ 358 if (month < 1 || month > 12 || day < 1) { 359 refclock_report(peer, CEVNT_BADTIME); 360 return; 361 } 362 if (pp->year % 4) { 363 if (day > day1tab[month - 1]) { 364 refclock_report(peer, CEVNT_BADTIME); 365 return; 366 } 367 for (i = 0; i < month - 1; i++) 368 day += day1tab[i]; 369 } else { 370 if (day > day2tab[month - 1]) { 371 refclock_report(peer, CEVNT_BADTIME); 372 return; 373 } 374 for (i = 0; i < month - 1; i++) 375 day += day2tab[i]; 376 } 377 pp->day = day; 378 379 /* 380 * Determine synchronization and last update 381 */ 382 if (!isdigit((unsigned char)dsec)) 383 pp->leap = LEAP_NOTINSYNC; 384 else { 385 pp->nsec = (dsec - '0') * 100000000; 386 pp->leap = LEAP_NOWARNING; 387 } 388 if (!refclock_process(pp)) 389 refclock_report(peer, CEVNT_BADTIME); 390 } 391 392 393 /* 394 * heath_poll - called by the transmit procedure 395 */ 396 static void 397 heath_poll( 398 int unit, 399 struct peer *peer 400 ) 401 { 402 struct refclockproc *pp; 403 int bits = TIOCM_RTS; 404 405 /* 406 * At each poll we check for timeout and toggle the RTS modem 407 * control line, then take a timestamp. Presumably, this is the 408 * event the radio captures to generate the timecode. 409 * Apparently, the radio takes about a second to make up its 410 * mind to send a timecode, so the receive timestamp is 411 * worthless. 412 */ 413 pp = peer->procptr; 414 415 /* 416 * We toggle the RTS modem control lead (GC-1000) and sent a T 417 * (GC-1001 II) to kick a timecode loose from the radio. This 418 * code works only for POSIX and SYSV interfaces. With bsd you 419 * are on your own. We take a timestamp between the up and down 420 * edges to lengthen the pulse, which should be about 50 usec on 421 * a Sun IPC. With hotshot CPUs, the pulse might get too short. 422 * Later. 423 * 424 * Bug 689: Even though we no longer support the GC-1001 II, 425 * I'm leaving the 'T' write in for timing purposes. 426 */ 427 if (ioctl(pp->io.fd, TIOCMBIC, (char *)&bits) < 0) 428 refclock_report(peer, CEVNT_FAULT); 429 get_systime(&pp->lastrec); 430 if (refclock_write(peer, "T", 1, "T") != 1) 431 refclock_report(peer, CEVNT_FAULT); 432 ioctl(pp->io.fd, TIOCMBIS, (char *)&bits); 433 if (pp->coderecv == pp->codeproc) { 434 refclock_report(peer, CEVNT_TIMEOUT); 435 return; 436 } 437 pp->lastref = pp->lastrec; 438 refclock_receive(peer); 439 record_clock_stats(&peer->srcadr, pp->a_lastcode); 440 #ifdef DEBUG 441 if (debug) 442 printf("heath: timecode %d %s\n", pp->lencode, 443 pp->a_lastcode); 444 #endif 445 pp->polls++; 446 } 447 448 #else 449 NONEMPTY_TRANSLATION_UNIT 450 #endif /* REFCLOCK */ 451