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-rw-r--r--contrib/ntp/ntpd/refclock_heath.c487
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diff --git a/contrib/ntp/ntpd/refclock_heath.c b/contrib/ntp/ntpd/refclock_heath.c
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+++ b/contrib/ntp/ntpd/refclock_heath.c
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+/*
+ * refclock_heath - clock driver for Heath GC-1000 Most Accurate Clock
+ */
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#if defined(REFCLOCK) && defined(CLOCK_HEATH)
+
+#include <stdio.h>
+#include <ctype.h>
+#ifdef TIME_WITH_SYS_TIME
+# include <sys/time.h>
+# include <time.h>
+#else
+# ifdef TM_IN_SYS_TIME
+# include <sys/time.h>
+# else
+# include <time.h>
+# endif
+#endif
+#ifdef HAVE_SYS_IOCTL_H
+# include <sys/ioctl.h>
+#endif /* not HAVE_SYS_IOCTL_H */
+
+#include "ntpd.h"
+#include "ntp_io.h"
+#include "ntp_refclock.h"
+#include "ntp_stdlib.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.
+ *
+ * The internal DIPswitches should be set to operate at 1200 baud in
+ * MANUAL mode and the current year. The external DIPswitches should be
+ * set to GMT and 24-hour format, or to the host local time zone (with
+ * DST) and 12-hour format. It is very important that the year be
+ * set correctly in the DIPswitches. Otherwise, the day of year will be
+ * incorrect after 28 April[?] of a normal or leap year. In 12-hour mode
+ * with DST selected the clock will be incorrect by an hour for an
+ * indeterminate amount of time between 0000Z and 0200 on the day DST
+ * changes.
+ *
+ * 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.
+ *
+ * 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 SPEED232 B1200 /* uart speed (1200 baud) */
+#define PRECISION (-4) /* precision assumed (about 100 ms) */
+#define REFID "WWV\0" /* reference ID */
+#define DESCRIPTION "Heath GC-1000 Most Accurate Clock" /* WRU */
+
+#define LENHEATH 23 /* min timecode length */
+
+/*
+ * 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};
+
+/*
+ * Unit control structure
+ */
+struct heathunit {
+ int pollcnt; /* poll message counter */
+ l_fp tstamp; /* timestamp of last poll */
+};
+
+/*
+ * Function prototypes
+ */
+static int heath_start P((int, struct peer *));
+static void heath_shutdown P((int, struct peer *));
+static void heath_receive P((struct recvbuf *));
+static void heath_poll P((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 */
+};
+
+#if 0
+/*
+ * Gee, Unix so thoughfully omitted code to convert from a struct tm to
+ * a long, so I'll just have to ferret out the inverse myself, the hard way.
+ * (Newton's method.)
+ */
+#define timelocal(x) invert(x, localtime)
+/*
+ * comparetm compares two tm structures and returns -1 if the first
+ * is less than the second, 0 if they are equal, and +1 if the first
+ * is greater than the second. Only the year, month, day, hour, minute
+ * and second are compared. The yearday (Julian), day of week, and isdst
+ * are not compared.
+ */
+
+static int
+comparetm(
+ struct tm *a,
+ struct tm *b
+ )
+{
+ if (a->tm_year < b->tm_year ) return -1;
+ if (a->tm_year > b->tm_year ) return 1;
+ if (a->tm_mon < b->tm_mon ) return -1;
+ if (a->tm_mon > b->tm_mon ) return 1;
+ if (a->tm_mday < b->tm_mday ) return -1;
+ if (a->tm_mday > b->tm_mday ) return 1;
+ if (a->tm_hour < b->tm_hour ) return -1;
+ if (a->tm_hour > b->tm_hour ) return 1;
+ if (a->tm_min < b->tm_min ) return -1;
+ if (a->tm_min > b->tm_min ) return 1;
+ if (a->tm_sec < b->tm_sec ) return -1;
+ if (a->tm_sec > b->tm_sec ) return 1;
+ return 0;
+}
+
+static long
+invert (
+ struct tm *x,
+ struct tm *(*func)()
+ )
+{
+ struct tm *y;
+ int result;
+ long trial;
+ long lower=0L;
+ long upper=(long)((unsigned long)(~lower) >> 1);
+
+ do {
+ trial = (upper + lower) / 2L;
+ y = (*func)(&trial);
+ result = comparetm(x, y);
+ if (result < 0) upper = trial;
+ if (result > 0) lower = trial;
+ } while (result != 0);
+ return trial;
+}
+#endif /* 0 */
+
+
+/*
+ * heath_start - open the devices and initialize data for processing
+ */
+static int
+heath_start(
+ int unit,
+ struct peer *peer
+ )
+{
+ register struct heathunit *up;
+ struct refclockproc *pp;
+ int fd;
+ char device[20];
+
+ /*
+ * Open serial port
+ */
+ (void)sprintf(device, DEVICE, unit);
+ if (!(fd = refclock_open(device, SPEED232, 0)))
+ return (0);
+
+ /*
+ * Allocate and initialize unit structure
+ */
+ if (!(up = (struct heathunit *)
+ emalloc(sizeof(struct heathunit)))) {
+ (void) close(fd);
+ return (0);
+ }
+ memset((char *)up, 0, sizeof(struct heathunit));
+ 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);
+ free(up);
+ return (0);
+ }
+ pp->unitptr = (caddr_t)up;
+
+ /*
+ * Initialize miscellaneous variables
+ */
+ peer->precision = PRECISION;
+ peer->burst = NSTAGE;
+ pp->clockdesc = DESCRIPTION;
+ memcpy((char *)&pp->refid, REFID, 4);
+ up->pollcnt = 2;
+ return (1);
+}
+
+
+/*
+ * heath_shutdown - shut down the clock
+ */
+static void
+heath_shutdown(
+ int unit,
+ struct peer *peer
+ )
+{
+ register struct heathunit *up;
+ struct refclockproc *pp;
+
+ pp = peer->procptr;
+ up = (struct heathunit *)pp->unitptr;
+ io_closeclock(&pp->io);
+ free(up);
+}
+
+
+/*
+ * heath_receive - receive data from the serial interface
+ */
+static void
+heath_receive(
+ struct recvbuf *rbufp
+ )
+{
+ register struct heathunit *up;
+ 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;
+ up = (struct heathunit *)pp->unitptr;
+ pp->lencode = refclock_gtlin(rbufp, pp->a_lastcode, BMAX, &trtmp);
+
+ /*
+ * We get a buffer and timestamp for each <cr>; however, we use
+ * the timestamp captured at the RTS modem control line toggle
+ * on the assumption that's what the radio bases the timecode
+ * on. Apparently, the radio takes about a second to make up its
+ * mind to send a timecode, so the receive timestamp is
+ * worthless.
+ */
+ pp->lastrec = up->tstamp;
+ up->pollcnt = 2;
+#ifdef DEBUG
+ if (debug)
+ printf("heath: timecode %d %s\n", pp->lencode,
+ pp->a_lastcode);
+#endif
+
+ /*
+ * 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.
+ */
+ if (pp->lencode < LENHEATH) {
+ refclock_report(peer, CEVNT_BADREPLY);
+ return;
+ }
+
+ /*
+ * Timecode format: "hh:mm:ss.f AM mm/dd/yy"
+ */
+ 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;
+ }
+
+ /*
+ * If AM or PM is received, assume the clock is displaying local
+ * time. First, convert to 24-hour format.
+ */
+
+ switch (a[1]) {
+ case 'P':
+ if (12 > pp->hour)
+ pp->hour += 12;
+ break;
+
+ case 'A':
+ if (12 == pp->hour)
+ pp->hour -= 12;
+ break;
+ }
+
+ /*
+ * Now make a struct tm out of it, convert to UTC, and
+ * repopulate pp->
+ */
+
+ if (' ' != a[1]) {
+ struct tm t, *q;
+ time_t l;
+
+ t.tm_sec = pp->second;
+ t.tm_min = pp->minute;
+ t.tm_hour = pp->hour;
+ t.tm_mday = day; /* not converted to yday yet */
+ t.tm_mon = month-1; /* ditto */
+ t.tm_year = pp->year;
+ if ( t.tm_year < YEAR_PIVOT ) t.tm_year += 100; /* Y2KFixes */
+
+ t.tm_wday = -1; /* who knows? */
+ t.tm_yday = -1; /* who knows? */
+ t.tm_isdst = -1; /* who knows? */
+
+ l = mktime(&t);
+ if (l == -1) {
+ /* HMS: do we want to do this? */
+ refclock_report(peer, CEVNT_BADTIME);
+ return;
+ }
+ q = gmtime(&l);
+
+ pp->year = q->tm_year;
+ month = q->tm_mon+1;
+ day = q->tm_mday; /* still not converted */
+ pp->hour = q->tm_hour;
+ /* pp->minute = q->tm_min; GC-1000 cannot adjust timezone */
+ /* pp->second = q->tm_sec; by other than hour increments */
+ }
+
+
+
+ /*
+ * 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.
+ *
+ * Yes, I know this code incorrectly thinks that 2000 is a leap
+ * year; but, the latest year that can be set by the DIPswitches
+ * is 1997 anyay. Life is short.
+ * Hey! Year 2000 IS a leap year! Y2KFixes
+ */
+ 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->msec = (dsec - '0') * 100;
+ 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
+ )
+{
+ register struct heathunit *up;
+ 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.
+ */
+ pp = peer->procptr;
+ up = (struct heathunit *)pp->unitptr;
+ pp->polls++;
+
+ /*
+ * We toggle the RTS modem control lead 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.
+ */
+ if (ioctl(pp->io.fd, TIOCMBIC, (char *)&bits) < 0)
+ refclock_report(peer, CEVNT_FAULT);
+ get_systime(&up->tstamp);
+ ioctl(pp->io.fd, TIOCMBIS, (char *)&bits);
+ if (peer->burst > 0)
+ return;
+ if (pp->coderecv == pp->codeproc) {
+ refclock_report(peer, CEVNT_TIMEOUT);
+ return;
+ }
+ record_clock_stats(&peer->srcadr, pp->a_lastcode);
+ refclock_receive(peer);
+ peer->burst = NSTAGE;
+}
+
+#else
+int refclock_heath_bs;
+#endif /* REFCLOCK */
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