xref: /freebsd/contrib/ntp/ntpd/refclock_pst.c (revision aa0a1e58)
1 /*
2  * refclock_pst - clock driver for PSTI/Traconex WWV/WWVH receivers
3  */
4 
5 #ifdef HAVE_CONFIG_H
6 #include <config.h>
7 #endif
8 
9 #if defined(REFCLOCK) && defined(CLOCK_PST)
10 
11 #include "ntpd.h"
12 #include "ntp_io.h"
13 #include "ntp_refclock.h"
14 #include "ntp_stdlib.h"
15 
16 #include <stdio.h>
17 #include <ctype.h>
18 
19 /*
20  * This driver supports the PSTI 1010 and Traconex 1020 WWV/WWVH
21  * Receivers. No specific claim of accuracy is made for these receiver,
22  * but actual experience suggests that 10 ms would be a conservative
23  * assumption.
24  *
25  * The DIPswitches should be set for 9600 bps line speed, 24-hour day-
26  * of-year format and UTC time zone. Automatic correction for DST should
27  * be disabled. It is very important that the year be set correctly in
28  * the DIPswitches; otherwise, the day of year will be incorrect after
29  * 28 April of a normal or leap year. The propagation delay DIPswitches
30  * should be set according to the distance from the transmitter for both
31  * WWV and WWVH, as described in the instructions. While the delay can
32  * be set only to within 11 ms, the fudge time1 parameter can be used
33  * for vernier corrections.
34  *
35  * Using the poll sequence QTQDQM, the response timecode is in three
36  * sections totalling 50 ASCII printing characters, as concatenated by
37  * the driver, in the following format:
38  *
39  * ahh:mm:ss.fffs<cr> yy/dd/mm/ddd<cr> frdzycchhSSFTttttuuxx<cr>
40  *
41  *	on-time = first <cr>
42  *	hh:mm:ss.fff = hours, minutes, seconds, milliseconds
43  *	a = AM/PM indicator (' ' for 24-hour mode)
44  *	yy = year (from internal switches)
45  *	dd/mm/ddd = day of month, month, day of year
46  *	s = daylight-saving indicator (' ' for 24-hour mode)
47  *	f = frequency enable (O = all frequencies enabled)
48  *	r = baud rate (3 = 1200, 6 = 9600)
49  *	d = features indicator (@ = month/day display enabled)
50  *	z = time zone (0 = UTC)
51  *	y = year (5 = 91)
52  *	cc = WWV propagation delay (52 = 22 ms)
53  *	hh = WWVH propagation delay (81 = 33 ms)
54  *	SS = status (80 or 82 = operating correctly)
55  *	F = current receive frequency (4 = 15 MHz)
56  *	T = transmitter (C = WWV, H = WWVH)
57  *	tttt = time since last update (0000 = minutes)
58  *	uu = flush character (03 = ^c)
59  *	xx = 94 (unknown)
60  *
61  * The alarm condition is indicated by other than '8' at A, which occurs
62  * during initial synchronization and when received signal is lost for
63  * an extended period; unlock condition is indicated by other than
64  * "0000" in the tttt subfield at Q.
65  *
66  * Fudge Factors
67  *
68  * There are no special fudge factors other than the generic.
69  */
70 
71 /*
72  * Interface definitions
73  */
74 #define	DEVICE		"/dev/wwv%d" /* device name and unit */
75 #define	SPEED232	B9600	/* uart speed (9600 baud) */
76 #define	PRECISION	(-10)	/* precision assumed (about 1 ms) */
77 #define	WWVREFID	"WWV\0"	/* WWV reference ID */
78 #define	WWVHREFID	"WWVH"	/* WWVH reference ID */
79 #define	DESCRIPTION	"PSTI/Traconex WWV/WWVH Receiver" /* WRU */
80 #define PST_PHI		(10e-6)	/* max clock oscillator offset */
81 #define LENPST		46	/* min timecode length */
82 
83 /*
84  * Unit control structure
85  */
86 struct pstunit {
87 	int	tcswitch;	/* timecode switch */
88 	char	*lastptr;	/* pointer to timecode data */
89 };
90 
91 /*
92  * Function prototypes
93  */
94 static	int	pst_start	P((int, struct peer *));
95 static	void	pst_shutdown	P((int, struct peer *));
96 static	void	pst_receive	P((struct recvbuf *));
97 static	void	pst_poll	P((int, struct peer *));
98 
99 /*
100  * Transfer vector
101  */
102 struct	refclock refclock_pst = {
103 	pst_start,		/* start up driver */
104 	pst_shutdown,		/* shut down driver */
105 	pst_poll,		/* transmit poll message */
106 	noentry,		/* not used (old pst_control) */
107 	noentry,		/* initialize driver */
108 	noentry,		/* not used (old pst_buginfo) */
109 	NOFLAGS			/* not used */
110 };
111 
112 
113 /*
114  * pst_start - open the devices and initialize data for processing
115  */
116 static int
117 pst_start(
118 	int unit,
119 	struct peer *peer
120 	)
121 {
122 	register struct pstunit *up;
123 	struct refclockproc *pp;
124 	int fd;
125 	char device[20];
126 
127 	/*
128 	 * Open serial port. Use CLK line discipline, if available.
129 	 */
130 	(void)sprintf(device, DEVICE, unit);
131 	if (!(fd = refclock_open(device, SPEED232, LDISC_CLK)))
132 		return (0);
133 
134 	/*
135 	 * Allocate and initialize unit structure
136 	 */
137 	if (!(up = (struct pstunit *)emalloc(sizeof(struct pstunit)))) {
138 		(void) close(fd);
139 		return (0);
140 	}
141 	memset((char *)up, 0, sizeof(struct pstunit));
142 	pp = peer->procptr;
143 	pp->io.clock_recv = pst_receive;
144 	pp->io.srcclock = (caddr_t)peer;
145 	pp->io.datalen = 0;
146 	pp->io.fd = fd;
147 	if (!io_addclock(&pp->io)) {
148 		(void) close(fd);
149 		free(up);
150 		return (0);
151 	}
152 	pp->unitptr = (caddr_t)up;
153 
154 	/*
155 	 * Initialize miscellaneous variables
156 	 */
157 	peer->precision = PRECISION;
158 	pp->clockdesc = DESCRIPTION;
159 	memcpy((char *)&pp->refid, WWVREFID, 4);
160 	peer->burst = MAXSTAGE;
161 	return (1);
162 }
163 
164 
165 /*
166  * pst_shutdown - shut down the clock
167  */
168 static void
169 pst_shutdown(
170 	int unit,
171 	struct peer *peer
172 	)
173 {
174 	register struct pstunit *up;
175 	struct refclockproc *pp;
176 
177 	pp = peer->procptr;
178 	up = (struct pstunit *)pp->unitptr;
179 	io_closeclock(&pp->io);
180 	free(up);
181 }
182 
183 
184 /*
185  * pst_receive - receive data from the serial interface
186  */
187 static void
188 pst_receive(
189 	struct recvbuf *rbufp
190 	)
191 {
192 	register struct pstunit *up;
193 	struct refclockproc *pp;
194 	struct peer *peer;
195 	l_fp trtmp;
196 	u_long ltemp;
197 	char ampmchar;		/* AM/PM indicator */
198 	char daychar;		/* standard/daylight indicator */
199 	char junque[10];	/* "yy/dd/mm/" discard */
200 	char info[14];		/* "frdzycchhSSFT" clock info */
201 
202 	/*
203 	 * Initialize pointers and read the timecode and timestamp
204 	 */
205 	peer = (struct peer *)rbufp->recv_srcclock;
206 	pp = peer->procptr;
207 	up = (struct pstunit *)pp->unitptr;
208 	up->lastptr += refclock_gtlin(rbufp, up->lastptr, pp->a_lastcode
209 	    + BMAX - 2 - up->lastptr, &trtmp);
210 	*up->lastptr++ = ' ';
211 	*up->lastptr = '\0';
212 
213 	/*
214 	 * Note we get a buffer and timestamp for each <cr>, but only
215 	 * the first timestamp is retained.
216 	 */
217 	if (up->tcswitch == 0)
218 		pp->lastrec = trtmp;
219 	up->tcswitch++;
220 	pp->lencode = up->lastptr - pp->a_lastcode;
221 	if (up->tcswitch < 3)
222 		return;
223 
224 	/*
225 	 * We get down to business, check the timecode format and decode
226 	 * its contents. If the timecode has invalid length or is not in
227 	 * proper format, we declare bad format and exit.
228 	 */
229 	if (pp->lencode < LENPST) {
230 		refclock_report(peer, CEVNT_BADREPLY);
231 		return;
232 	}
233 
234 	/*
235 	 * Timecode format:
236 	 * "ahh:mm:ss.fffs yy/dd/mm/ddd frdzycchhSSFTttttuuxx"
237 	 */
238 	if (sscanf(pp->a_lastcode,
239 	    "%c%2d:%2d:%2d.%3ld%c %9s%3d%13s%4ld",
240 	    &ampmchar, &pp->hour, &pp->minute, &pp->second, &pp->nsec,
241 	    &daychar, junque, &pp->day, info, &ltemp) != 10) {
242 		refclock_report(peer, CEVNT_BADREPLY);
243 		return;
244 	}
245 	pp->nsec *= 1000000;
246 
247 	/*
248 	 * Decode synchronization, quality and last update. If
249 	 * unsynchronized, set the leap bits accordingly and exit. Once
250 	 * synchronized, the dispersion depends only on when the clock
251 	 * was last heard, which depends on the time since last update,
252 	 * as reported by the clock.
253 	 */
254 	if (info[9] != '8')
255 		pp->leap = LEAP_NOTINSYNC;
256 	if (info[12] == 'H')
257 		memcpy((char *)&pp->refid, WWVHREFID, 4);
258 	else
259 		memcpy((char *)&pp->refid, WWVREFID, 4);
260 	if (peer->stratum <= 1)
261 		peer->refid = pp->refid;
262 	if (ltemp == 0)
263 		pp->lastref = pp->lastrec;
264 	pp->disp = PST_PHI * ltemp * 60;
265 
266 	/*
267 	 * Process the new sample in the median filter and determine the
268 	 * timecode timestamp.
269 	 */
270 	if (!refclock_process(pp))
271 		refclock_report(peer, CEVNT_BADTIME);
272 	else if (peer->disp > MAXDISTANCE)
273 		refclock_receive(peer);
274 }
275 
276 
277 /*
278  * pst_poll - called by the transmit procedure
279  */
280 static void
281 pst_poll(
282 	int unit,
283 	struct peer *peer
284 	)
285 {
286 	register struct pstunit *up;
287 	struct refclockproc *pp;
288 
289 	/*
290 	 * Time to poll the clock. The PSTI/Traconex clock responds to a
291 	 * "QTQDQMT" by returning a timecode in the format specified
292 	 * above. Note there is no checking on state, since this may not
293 	 * be the only customer reading the clock. Only one customer
294 	 * need poll the clock; all others just listen in. If the clock
295 	 * becomes unreachable, declare a timeout and keep going.
296 	 */
297 	pp = peer->procptr;
298 	up = (struct pstunit *)pp->unitptr;
299 	up->tcswitch = 0;
300 	up->lastptr = pp->a_lastcode;
301 	if (write(pp->io.fd, "QTQDQMT", 6) != 6)
302 		refclock_report(peer, CEVNT_FAULT);
303 	if (peer->burst > 0)
304 		return;
305 	if (pp->coderecv == pp->codeproc) {
306 		refclock_report(peer, CEVNT_TIMEOUT);
307 		return;
308 	}
309 	refclock_receive(peer);
310 	record_clock_stats(&peer->srcadr, pp->a_lastcode);
311 #ifdef DEBUG
312 	if (debug)
313 		printf("pst: timecode %d %s\n", pp->lencode,
314 		    pp->a_lastcode);
315 #endif
316 	peer->burst = MAXSTAGE;
317 	pp->polls++;
318 }
319 
320 #else
321 int refclock_pst_int;
322 #endif /* REFCLOCK */
323