1 /* 2 * refclock_heath - clock driver for Heath GC-1000 and and GC-1000 II 3 */ 4 #ifdef HAVE_CONFIG_H 5 #include <config.h> 6 #endif 7 8 #if defined(REFCLOCK) && defined(CLOCK_HEATH) 9 10 #include "ntpd.h" 11 #include "ntp_io.h" 12 #include "ntp_refclock.h" 13 #include "ntp_stdlib.h" 14 15 #include <stdio.h> 16 #include <ctype.h> 17 18 #ifdef HAVE_SYS_IOCTL_H 19 # include <sys/ioctl.h> 20 #endif /* not HAVE_SYS_IOCTL_H */ 21 22 /* 23 * This driver supports the Heath GC-1000 Most Accurate Clock, with 24 * RS232C Output Accessory. This is a WWV/WWVH receiver somewhat less 25 * robust than other supported receivers. Its claimed accuracy is 100 ms 26 * when actually synchronized to the broadcast signal, but this doesn't 27 * happen even most of the time, due to propagation conditions, ambient 28 * noise sources, etc. When not synchronized, the accuracy is at the 29 * whim of the internal clock oscillator, which can wander into the 30 * sunset without warning. Since the indicated precision is 100 ms, 31 * expect a host synchronized only to this thing to wander to and fro, 32 * occasionally being rudely stepped when the offset exceeds the default 33 * clock_max of 128 ms. 34 * 35 * There are two GC-1000 versions supported by this driver. The original 36 * GC-1000 with RS-232 output first appeared in 1983, but dissapeared 37 * from the market a few years later. The GC-1000 II with RS-232 output 38 * first appeared circa 1990, but apparently is no longer manufactured. 39 * The two models differ considerably, both in interface and commands. 40 * The GC-1000 has a pseudo-bipolar timecode output triggered by a RTS 41 * transition. The timecode includes both the day of year and time of 42 * day. The GC-1000 II has a true bipolar output and a complement of 43 * single character commands. The timecode includes only the time of 44 * day. 45 * 46 * GC-1000 47 * 48 * The internal DIPswitches should be set to operate in MANUAL mode. The 49 * external DIPswitches should be set to GMT and 24-hour format. 50 * 51 * In MANUAL mode the clock responds to a rising edge of the request to 52 * send (RTS) modem control line by sending the timecode. Therefore, it 53 * is necessary that the operating system implement the TIOCMBIC and 54 * TIOCMBIS ioctl system calls and TIOCM_RTS control bit. Present 55 * restrictions require the use of a POSIX-compatible programming 56 * interface, although other interfaces may work as well. 57 * 58 * A simple hardware modification to the clock can be made which 59 * prevents the clock hearing the request to send (RTS) if the HI SPEC 60 * lamp is out. Route the HISPEC signal to the tone decoder board pin 61 * 19, from the display, pin 19. Isolate pin 19 of the decoder board 62 * first, but maintain connection with pin 10. Also isolate pin 38 of 63 * the CPU on the tone board, and use half an added 7400 to gate the 64 * original signal to pin 38 with that from pin 19. 65 * 66 * The clock message consists of 23 ASCII printing characters in the 67 * following format: 68 * 69 * hh:mm:ss.f AM dd/mm/yr<cr> 70 * 71 * hh:mm:ss.f = hours, minutes, seconds 72 * f = deciseconds ('?' when out of spec) 73 * AM/PM/bb = blank in 24-hour mode 74 * dd/mm/yr = day, month, year 75 * 76 * The alarm condition is indicated by '?', rather than a digit, at f. 77 * Note that 0?:??:??.? is displayed before synchronization is first 78 * established and hh:mm:ss.? once synchronization is established and 79 * then lost again for about a day. 80 * 81 * GC-1000 II 82 * 83 * Commands consist of a single letter and are case sensitive. When 84 * enterred in lower case, a description of the action performed is 85 * displayed. When enterred in upper case the action is performed. 86 * Following is a summary of descriptions as displayed by the clock: 87 * 88 * The clock responds with a command The 'A' command returns an ASCII 89 * local time string: HH:MM:SS.T xx<CR>, where 90 * 91 * HH = hours 92 * MM = minutes 93 * SS = seconds 94 * T = tenths-of-seconds 95 * xx = 'AM', 'PM', or ' ' 96 * <CR> = carriage return 97 * 98 * The 'D' command returns 24 pairs of bytes containing the variable 99 * divisor value at the end of each of the previous 24 hours. This 100 * allows the timebase trimming process to be observed. UTC hour 00 is 101 * always returned first. The first byte of each pair is the high byte 102 * of (variable divisor * 16); the second byte is the low byte of 103 * (variable divisor * 16). For example, the byte pair 3C 10 would be 104 * returned for a divisor of 03C1 hex (961 decimal). 105 * 106 * The 'I' command returns: | TH | TL | ER | DH | DL | U1 | I1 | I2 | , 107 * where 108 * 109 * TH = minutes since timebase last trimmed (high byte) 110 * TL = minutes since timebase last trimmed (low byte) 111 * ER = last accumulated error in 1.25 ms increments 112 * DH = high byte of (current variable divisor * 16) 113 * DL = low byte of (current variable divisor * 16) 114 * U1 = UT1 offset (/.1 s): | + | 4 | 2 | 1 | 0 | 0 | 0 | 0 | 115 * I1 = information byte 1: | W | C | D | I | U | T | Z | 1 | , 116 * where 117 * 118 * W = set by WWV(H) 119 * C = CAPTURE LED on 120 * D = TRIM DN LED on 121 * I = HI SPEC LED on 122 * U = TRIM UP LED on 123 * T = DST switch on 124 * Z = UTC switch on 125 * 1 = UT1 switch on 126 * 127 * I2 = information byte 2: | 8 | 8 | 4 | 2 | 1 | D | d | S | , 128 * where 129 * 130 * 8, 8, 4, 2, 1 = TIME ZONE switch settings 131 * D = DST bit (#55) in last-received frame 132 * d = DST bit (#2) in last-received frame 133 * S = clock is in simulation mode 134 * 135 * The 'P' command returns 24 bytes containing the number of frames 136 * received without error during UTC hours 00 through 23, providing an 137 * indication of hourly propagation. These bytes are updated each hour 138 * to reflect the previous 24 hour period. UTC hour 00 is always 139 * returned first. 140 * 141 * The 'T' command returns the UTC time: | HH | MM | SS | T0 | , where 142 * HH = tens-of-hours and hours (packed BCD) 143 * MM = tens-of-minutes and minutes (packed BCD) 144 * SS = tens-of-seconds and seconds (packed BCD) 145 * T = tenths-of-seconds (BCD) 146 * 147 * Fudge Factors 148 * 149 * A fudge time1 value of .04 s appears to center the clock offset 150 * residuals. The fudge time2 parameter is the local time offset east of 151 * Greenwich, which depends on DST. Sorry about that, but the clock 152 * gives no hint on what the DIPswitches say. 153 */ 154 155 /* 156 * Interface definitions 157 */ 158 #define DEVICE "/dev/heath%d" /* device name and unit */ 159 #define PRECISION (-4) /* precision assumed (about 100 ms) */ 160 #define REFID "WWV\0" /* reference ID */ 161 #define DESCRIPTION "Heath GC-1000 Most Accurate Clock" /* WRU */ 162 163 #define LENHEATH1 23 /* min timecode length */ 164 #define LENHEATH2 13 /* min timecode length */ 165 166 /* 167 * Tables to compute the ddd of year form icky dd/mm timecode. Viva la 168 * leap. 169 */ 170 static int day1tab[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; 171 static int day2tab[] = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; 172 173 /* 174 * Baud rate table. The GC-1000 supports 1200, 2400 and 4800; the 175 * GC-1000 II supports only 9600. 176 */ 177 static int speed[] = {B1200, B2400, B4800, B9600}; 178 179 /* 180 * Unit control structure 181 */ 182 struct heathunit { 183 int pollcnt; /* poll message counter */ 184 l_fp tstamp; /* timestamp of last poll */ 185 }; 186 187 /* 188 * Function prototypes 189 */ 190 static int heath_start P((int, struct peer *)); 191 static void heath_shutdown P((int, struct peer *)); 192 static void heath_receive P((struct recvbuf *)); 193 static void heath_poll P((int, struct peer *)); 194 195 /* 196 * Transfer vector 197 */ 198 struct refclock refclock_heath = { 199 heath_start, /* start up driver */ 200 heath_shutdown, /* shut down driver */ 201 heath_poll, /* transmit poll message */ 202 noentry, /* not used (old heath_control) */ 203 noentry, /* initialize driver */ 204 noentry, /* not used (old heath_buginfo) */ 205 NOFLAGS /* not used */ 206 }; 207 208 209 /* 210 * heath_start - open the devices and initialize data for processing 211 */ 212 static int 213 heath_start( 214 int unit, 215 struct peer *peer 216 ) 217 { 218 register struct heathunit *up; 219 struct refclockproc *pp; 220 int fd; 221 char device[20]; 222 223 /* 224 * Open serial port 225 */ 226 (void)sprintf(device, DEVICE, unit); 227 if (!(fd = refclock_open(device, speed[peer->ttlmax & 0x3], 0))) 228 return (0); 229 230 /* 231 * Allocate and initialize unit structure 232 */ 233 if (!(up = (struct heathunit *) 234 emalloc(sizeof(struct heathunit)))) { 235 (void) close(fd); 236 return (0); 237 } 238 memset((char *)up, 0, sizeof(struct heathunit)); 239 pp = peer->procptr; 240 pp->io.clock_recv = heath_receive; 241 pp->io.srcclock = (caddr_t)peer; 242 pp->io.datalen = 0; 243 pp->io.fd = fd; 244 if (!io_addclock(&pp->io)) { 245 (void) close(fd); 246 free(up); 247 return (0); 248 } 249 pp->unitptr = (caddr_t)up; 250 251 /* 252 * Initialize miscellaneous variables 253 */ 254 peer->precision = PRECISION; 255 peer->burst = NSTAGE; 256 pp->clockdesc = DESCRIPTION; 257 memcpy((char *)&pp->refid, REFID, 4); 258 up->pollcnt = 2; 259 return (1); 260 } 261 262 263 /* 264 * heath_shutdown - shut down the clock 265 */ 266 static void 267 heath_shutdown( 268 int unit, 269 struct peer *peer 270 ) 271 { 272 register struct heathunit *up; 273 struct refclockproc *pp; 274 275 pp = peer->procptr; 276 up = (struct heathunit *)pp->unitptr; 277 io_closeclock(&pp->io); 278 free(up); 279 } 280 281 282 /* 283 * heath_receive - receive data from the serial interface 284 */ 285 static void 286 heath_receive( 287 struct recvbuf *rbufp 288 ) 289 { 290 register struct heathunit *up; 291 struct refclockproc *pp; 292 struct peer *peer; 293 l_fp trtmp; 294 int month, day; 295 int i; 296 char dsec, a[5]; 297 298 /* 299 * Initialize pointers and read the timecode and timestamp 300 */ 301 peer = (struct peer *)rbufp->recv_srcclock; 302 pp = peer->procptr; 303 up = (struct heathunit *)pp->unitptr; 304 pp->lencode = refclock_gtlin(rbufp, pp->a_lastcode, BMAX, 305 &trtmp); 306 307 /* 308 * We get a buffer and timestamp for each <cr>; however, we use 309 * the timestamp captured at the RTS modem control line toggle 310 * on the assumption that's what the radio bases the timecode 311 * on. Apparently, the radio takes about a second to make up its 312 * mind to send a timecode, so the receive timestamp is 313 * worthless. 314 */ 315 pp->lastrec = up->tstamp; 316 up->pollcnt = 2; 317 #ifdef DEBUG 318 if (debug) 319 printf("heath: timecode %d %s\n", pp->lencode, 320 pp->a_lastcode); 321 #endif 322 323 /* 324 * We get down to business, check the timecode format and decode 325 * its contents. If the timecode has invalid length or is not in 326 * proper format, we declare bad format and exit. 327 */ 328 switch (pp->lencode) { 329 330 /* 331 * GC-1000 timecode format: "hh:mm:ss.f AM mm/dd/yy" 332 * GC-1000 II timecode format: "hh:mm:ss.f " 333 */ 334 case LENHEATH1: 335 if (sscanf(pp->a_lastcode, 336 "%2d:%2d:%2d.%c%5c%2d/%2d/%2d", &pp->hour, 337 &pp->minute, &pp->second, &dsec, a, &month, &day, 338 &pp->year) != 8) { 339 refclock_report(peer, CEVNT_BADREPLY); 340 return; 341 } 342 break; 343 344 /* 345 * GC-1000 II timecode format: "hh:mm:ss.f " 346 */ 347 case LENHEATH2: 348 if (sscanf(pp->a_lastcode, "%2d:%2d:%2d.%c", &pp->hour, 349 &pp->minute, &pp->second, &dsec) != 4) { 350 refclock_report(peer, CEVNT_BADREPLY); 351 return; 352 } 353 break; 354 355 default: 356 refclock_report(peer, CEVNT_BADREPLY); 357 return; 358 } 359 360 /* 361 * We determine the day of the year from the DIPswitches. This 362 * should be fixed, since somebody might forget to set them. 363 * Someday this hazard will be fixed by a fiendish scheme that 364 * looks at the timecode and year the radio shows, then computes 365 * the residue of the seconds mod the seconds in a leap cycle. 366 * If in the third year of that cycle and the third and later 367 * months of that year, add one to the day. Then, correct the 368 * timecode accordingly. Icky pooh. This bit of nonsense could 369 * be avoided if the engineers had been required to write a 370 * device driver before finalizing the timecode format. 371 */ 372 if (month < 1 || month > 12 || day < 1) { 373 refclock_report(peer, CEVNT_BADTIME); 374 return; 375 } 376 if (pp->year % 4) { 377 if (day > day1tab[month - 1]) { 378 refclock_report(peer, CEVNT_BADTIME); 379 return; 380 } 381 for (i = 0; i < month - 1; i++) 382 day += day1tab[i]; 383 } else { 384 if (day > day2tab[month - 1]) { 385 refclock_report(peer, CEVNT_BADTIME); 386 return; 387 } 388 for (i = 0; i < month - 1; i++) 389 day += day2tab[i]; 390 } 391 pp->day = day; 392 393 /* 394 * Determine synchronization and last update 395 */ 396 if (!isdigit((int)dsec)) 397 pp->leap = LEAP_NOTINSYNC; 398 else { 399 pp->msec = (dsec - '0') * 100; 400 pp->leap = LEAP_NOWARNING; 401 } 402 if (!refclock_process(pp)) 403 refclock_report(peer, CEVNT_BADTIME); 404 } 405 406 407 /* 408 * heath_poll - called by the transmit procedure 409 */ 410 static void 411 heath_poll( 412 int unit, 413 struct peer *peer 414 ) 415 { 416 register struct heathunit *up; 417 struct refclockproc *pp; 418 int bits = TIOCM_RTS; 419 420 /* 421 * At each poll we check for timeout and toggle the RTS modem 422 * control line, then take a timestamp. Presumably, this is the 423 * event the radio captures to generate the timecode. 424 */ 425 pp = peer->procptr; 426 up = (struct heathunit *)pp->unitptr; 427 pp->polls++; 428 429 /* 430 * We toggle the RTS modem control lead (GC-1000) and sent a T 431 * (GC-1000 II) to kick a timecode loose from the radio. This 432 * code works only for POSIX and SYSV interfaces. With bsd you 433 * are on your own. We take a timestamp between the up and down 434 * edges to lengthen the pulse, which should be about 50 usec on 435 * a Sun IPC. With hotshot CPUs, the pulse might get too short. 436 * Later. 437 */ 438 if (ioctl(pp->io.fd, TIOCMBIC, (char *)&bits) < 0) 439 refclock_report(peer, CEVNT_FAULT); 440 get_systime(&up->tstamp); 441 ioctl(pp->io.fd, TIOCMBIS, (char *)&bits); 442 if (write(pp->io.fd, "T", 1) != 1) 443 refclock_report(peer, CEVNT_FAULT); 444 if (peer->burst > 0) 445 return; 446 if (pp->coderecv == pp->codeproc) { 447 refclock_report(peer, CEVNT_TIMEOUT); 448 return; 449 } 450 record_clock_stats(&peer->srcadr, pp->a_lastcode); 451 refclock_receive(peer); 452 peer->burst = NSTAGE; 453 } 454 455 #else 456 int refclock_heath_bs; 457 #endif /* REFCLOCK */ 458