/* * refclock_heath - clock driver for Heath GC-1000 * (but no longer the GC-1001 Model II, which apparently never worked) */ #ifdef HAVE_CONFIG_H # include <config.h> #endif #if defined(REFCLOCK) && defined(CLOCK_HEATH) #include "ntpd.h" #include "ntp_io.h" #include "ntp_refclock.h" #include "ntp_stdlib.h" #include <stdio.h> #include <ctype.h> #ifdef HAVE_SYS_IOCTL_H # include <sys/ioctl.h> #endif /* not HAVE_SYS_IOCTL_H */ /* * This driver supports the Heath GC-1000 Most Accurate Clock, with * RS232C Output Accessory. This is a WWV/WWVH receiver somewhat less * robust than other supported receivers. Its claimed accuracy is 100 ms * when actually synchronized to the broadcast signal, but this doesn't * happen even most of the time, due to propagation conditions, ambient * noise sources, etc. When not synchronized, the accuracy is at the * whim of the internal clock oscillator, which can wander into the * sunset without warning. Since the indicated precision is 100 ms, * expect a host synchronized only to this thing to wander to and fro, * occasionally being rudely stepped when the offset exceeds the default * clock_max of 128 ms. * * There were two GC-1000 versions supported by this driver. The original * GC-1000 with RS-232 output first appeared in 1983, but dissapeared * from the market a few years later. The GC-1001 II with RS-232 output * first appeared circa 1990, but apparently is no longer manufactured. * The two models differ considerably, both in interface and commands. * The GC-1000 has a pseudo-bipolar timecode output triggered by a RTS * transition. The timecode includes both the day of year and time of * day. The GC-1001 II has a true bipolar output and a complement of * single character commands. The timecode includes only the time of * day. * * The GC-1001 II was apparently never tested and, based on a Coverity * scan, apparently never worked [Bug 689]. Related code has been disabled. * * GC-1000 * * The internal DIPswitches should be set to operate in MANUAL mode. The * external DIPswitches should be set to GMT and 24-hour format. * * In MANUAL mode the clock responds to a rising edge of the request to * send (RTS) modem control line by sending the timecode. Therefore, it * is necessary that the operating system implement the TIOCMBIC and * TIOCMBIS ioctl system calls and TIOCM_RTS control bit. Present * restrictions require the use of a POSIX-compatible programming * interface, although other interfaces may work as well. * * A simple hardware modification to the clock can be made which * prevents the clock hearing the request to send (RTS) if the HI SPEC * lamp is out. Route the HISPEC signal to the tone decoder board pin * 19, from the display, pin 19. Isolate pin 19 of the decoder board * first, but maintain connection with pin 10. Also isolate pin 38 of * the CPU on the tone board, and use half an added 7400 to gate the * original signal to pin 38 with that from pin 19. * * The clock message consists of 23 ASCII printing characters in the * following format: * * hh:mm:ss.f AM dd/mm/yr<cr> * * hh:mm:ss.f = hours, minutes, seconds * f = deciseconds ('?' when out of spec) * AM/PM/bb = blank in 24-hour mode * dd/mm/yr = day, month, year * * The alarm condition is indicated by '?', rather than a digit, at f. * Note that 0?:??:??.? is displayed before synchronization is first * established and hh:mm:ss.? once synchronization is established and * then lost again for about a day. * * GC-1001 II * * Commands consist of a single letter and are case sensitive. When * enterred in lower case, a description of the action performed is * displayed. When enterred in upper case the action is performed. * Following is a summary of descriptions as displayed by the clock: * * The clock responds with a command The 'A' command returns an ASCII * local time string: HH:MM:SS.T xx<CR>, where * * HH = hours * MM = minutes * SS = seconds * T = tenths-of-seconds * xx = 'AM', 'PM', or ' ' * <CR> = carriage return * * The 'D' command returns 24 pairs of bytes containing the variable * divisor value at the end of each of the previous 24 hours. This * allows the timebase trimming process to be observed. UTC hour 00 is * always returned first. The first byte of each pair is the high byte * of (variable divisor * 16); the second byte is the low byte of * (variable divisor * 16). For example, the byte pair 3C 10 would be * returned for a divisor of 03C1 hex (961 decimal). * * The 'I' command returns: | TH | TL | ER | DH | DL | U1 | I1 | I2 | , * where * * TH = minutes since timebase last trimmed (high byte) * TL = minutes since timebase last trimmed (low byte) * ER = last accumulated error in 1.25 ms increments * DH = high byte of (current variable divisor * 16) * DL = low byte of (current variable divisor * 16) * U1 = UT1 offset (/.1 s): | + | 4 | 2 | 1 | 0 | 0 | 0 | 0 | * I1 = information byte 1: | W | C | D | I | U | T | Z | 1 | , * where * * W = set by WWV(H) * C = CAPTURE LED on * D = TRIM DN LED on * I = HI SPEC LED on * U = TRIM UP LED on * T = DST switch on * Z = UTC switch on * 1 = UT1 switch on * * I2 = information byte 2: | 8 | 8 | 4 | 2 | 1 | D | d | S | , * where * * 8, 8, 4, 2, 1 = TIME ZONE switch settings * D = DST bit (#55) in last-received frame * d = DST bit (#2) in last-received frame * S = clock is in simulation mode * * The 'P' command returns 24 bytes containing the number of frames * received without error during UTC hours 00 through 23, providing an * indication of hourly propagation. These bytes are updated each hour * to reflect the previous 24 hour period. UTC hour 00 is always * returned first. * * The 'T' command returns the UTC time: | HH | MM | SS | T0 | , where * HH = tens-of-hours and hours (packed BCD) * MM = tens-of-minutes and minutes (packed BCD) * SS = tens-of-seconds and seconds (packed BCD) * T = tenths-of-seconds (BCD) * * Fudge Factors * * A fudge time1 value of .04 s appears to center the clock offset * residuals. The fudge time2 parameter is the local time offset east of * Greenwich, which depends on DST. Sorry about that, but the clock * gives no hint on what the DIPswitches say. */ /* * Interface definitions */ #define DEVICE "/dev/heath%d" /* device name and unit */ #define PRECISION (-4) /* precision assumed (about 100 ms) */ #define REFID "WWV\0" /* reference ID */ #define DESCRIPTION "Heath GC-1000 Most Accurate Clock" /* WRU */ #define LENHEATH1 23 /* min timecode length */ #if 0 /* BUG 689 */ #define LENHEATH2 13 /* min timecode length */ #endif /* * Tables to compute the ddd of year form icky dd/mm timecode. Viva la * leap. */ static int day1tab[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; static int day2tab[] = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}; /* * Baud rate table. The GC-1000 supports 1200, 2400 and 4800; the * GC-1001 II supports only 9600. */ static int speed[] = {B1200, B2400, B4800, B9600}; /* * Function prototypes */ static int heath_start (int, struct peer *); static void heath_shutdown (int, struct peer *); static void heath_receive (struct recvbuf *); static void heath_poll (int, struct peer *); /* * Transfer vector */ struct refclock refclock_heath = { heath_start, /* start up driver */ heath_shutdown, /* shut down driver */ heath_poll, /* transmit poll message */ noentry, /* not used (old heath_control) */ noentry, /* initialize driver */ noentry, /* not used (old heath_buginfo) */ NOFLAGS /* not used */ }; /* * heath_start - open the devices and initialize data for processing */ static int heath_start( int unit, struct peer *peer ) { struct refclockproc *pp; int fd; char device[20]; /* * Open serial port */ sprintf(device, DEVICE, unit); if (!(fd = refclock_open(device, speed[peer->ttl & 0x3], LDISC_REMOTE))) return (0); pp = peer->procptr; pp->io.clock_recv = heath_receive; pp->io.srcclock = (caddr_t)peer; pp->io.datalen = 0; pp->io.fd = fd; if (!io_addclock(&pp->io)) { (void) close(fd); return (0); } /* * Initialize miscellaneous variables */ peer->precision = PRECISION; peer->burst = NSTAGE; pp->clockdesc = DESCRIPTION; memcpy((char *)&pp->refid, REFID, 4); return (1); } /* * heath_shutdown - shut down the clock */ static void heath_shutdown( int unit, struct peer *peer ) { struct refclockproc *pp; pp = peer->procptr; io_closeclock(&pp->io); } /* * heath_receive - receive data from the serial interface */ static void heath_receive( struct recvbuf *rbufp ) { struct refclockproc *pp; struct peer *peer; l_fp trtmp; int month, day; int i; char dsec, a[5]; /* * Initialize pointers and read the timecode and timestamp */ peer = (struct peer *)rbufp->recv_srcclock; pp = peer->procptr; pp->lencode = refclock_gtlin(rbufp, pp->a_lastcode, BMAX, &trtmp); /* * We get down to business, check the timecode format and decode * its contents. If the timecode has invalid length or is not in * proper format, we declare bad format and exit. */ switch (pp->lencode) { /* * GC-1000 timecode format: "hh:mm:ss.f AM mm/dd/yy" * GC-1001 II timecode format: "hh:mm:ss.f " */ case LENHEATH1: if (sscanf(pp->a_lastcode, "%2d:%2d:%2d.%c%5c%2d/%2d/%2d", &pp->hour, &pp->minute, &pp->second, &dsec, a, &month, &day, &pp->year) != 8) { refclock_report(peer, CEVNT_BADREPLY); return; } break; #if 0 /* BUG 689 */ /* * GC-1001 II timecode format: "hh:mm:ss.f " */ case LENHEATH2: if (sscanf(pp->a_lastcode, "%2d:%2d:%2d.%c", &pp->hour, &pp->minute, &pp->second, &dsec) != 4) { refclock_report(peer, CEVNT_BADREPLY); return; } else { struct tm *tm_time_p; time_t now; time(&now); /* we should grab 'now' earlier */ tm_time_p = gmtime(&now); /* * There is a window of time around midnight * where this will Do The Wrong Thing. */ if (tm_time_p) { month = tm_time_p->tm_mon + 1; day = tm_time_p->tm_mday; } else { refclock_report(peer, CEVNT_FAULT); return; } } break; #endif default: refclock_report(peer, CEVNT_BADREPLY); return; } /* * We determine the day of the year from the DIPswitches. This * should be fixed, since somebody might forget to set them. * Someday this hazard will be fixed by a fiendish scheme that * looks at the timecode and year the radio shows, then computes * the residue of the seconds mod the seconds in a leap cycle. * If in the third year of that cycle and the third and later * months of that year, add one to the day. Then, correct the * timecode accordingly. Icky pooh. This bit of nonsense could * be avoided if the engineers had been required to write a * device driver before finalizing the timecode format. */ if (month < 1 || month > 12 || day < 1) { refclock_report(peer, CEVNT_BADTIME); return; } if (pp->year % 4) { if (day > day1tab[month - 1]) { refclock_report(peer, CEVNT_BADTIME); return; } for (i = 0; i < month - 1; i++) day += day1tab[i]; } else { if (day > day2tab[month - 1]) { refclock_report(peer, CEVNT_BADTIME); return; } for (i = 0; i < month - 1; i++) day += day2tab[i]; } pp->day = day; /* * Determine synchronization and last update */ if (!isdigit((int)dsec)) pp->leap = LEAP_NOTINSYNC; else { pp->nsec = (dsec - '0') * 100000000; pp->leap = LEAP_NOWARNING; } if (!refclock_process(pp)) refclock_report(peer, CEVNT_BADTIME); } /* * heath_poll - called by the transmit procedure */ static void heath_poll( int unit, struct peer *peer ) { struct refclockproc *pp; int bits = TIOCM_RTS; /* * At each poll we check for timeout and toggle the RTS modem * control line, then take a timestamp. Presumably, this is the * event the radio captures to generate the timecode. * Apparently, the radio takes about a second to make up its * mind to send a timecode, so the receive timestamp is * worthless. */ pp = peer->procptr; /* * We toggle the RTS modem control lead (GC-1000) and sent a T * (GC-1001 II) to kick a timecode loose from the radio. This * code works only for POSIX and SYSV interfaces. With bsd you * are on your own. We take a timestamp between the up and down * edges to lengthen the pulse, which should be about 50 usec on * a Sun IPC. With hotshot CPUs, the pulse might get too short. * Later. * * Bug 689: Even though we no longer support the GC-1001 II, * I'm leaving the 'T' write in for timing purposes. */ if (ioctl(pp->io.fd, TIOCMBIC, (char *)&bits) < 0) refclock_report(peer, CEVNT_FAULT); get_systime(&pp->lastrec); if (write(pp->io.fd, "T", 1) != 1) refclock_report(peer, CEVNT_FAULT); ioctl(pp->io.fd, TIOCMBIS, (char *)&bits); if (peer->burst > 0) return; if (pp->coderecv == pp->codeproc) { refclock_report(peer, CEVNT_TIMEOUT); return; } pp->lastref = pp->lastrec; refclock_receive(peer); record_clock_stats(&peer->srcadr, pp->a_lastcode); #ifdef DEBUG if (debug) printf("heath: timecode %d %s\n", pp->lencode, pp->a_lastcode); #endif peer->burst = MAXSTAGE; pp->polls++; } #else int refclock_heath_bs; #endif /* REFCLOCK */