xref: /freebsd/contrib/ntp/ntpd/refclock_pst.c (revision 4543ef516683042d46f3bd3bb8a4f3f746e00499)
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	(int, struct peer *);
95 static	void	pst_shutdown	(int, struct peer *);
96 static	void	pst_receive	(struct recvbuf *);
97 static	void	pst_poll	(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 	snprintf(device, sizeof(device), DEVICE, unit);
131 	fd = refclock_open(&peer->srcadr, device, SPEED232, LDISC_CLK);
132 	if (fd <= 0)
133 		return (0);
134 
135 	/*
136 	 * Allocate and initialize unit structure
137 	 */
138 	up = emalloc_zero(sizeof(*up));
139 	pp = peer->procptr;
140 	pp->io.clock_recv = pst_receive;
141 	pp->io.srcclock = peer;
142 	pp->io.datalen = 0;
143 	pp->io.fd = fd;
144 	if (!io_addclock(&pp->io)) {
145 		close(fd);
146 		pp->io.fd = -1;
147 		free(up);
148 		return (0);
149 	}
150 	pp->unitptr = up;
151 
152 	/*
153 	 * Initialize miscellaneous variables
154 	 */
155 	peer->precision = PRECISION;
156 	pp->clockdesc = DESCRIPTION;
157 	memcpy((char *)&pp->refid, WWVREFID, 4);
158 	return (1);
159 }
160 
161 
162 /*
163  * pst_shutdown - shut down the clock
164  */
165 static void
166 pst_shutdown(
167 	int unit,
168 	struct peer *peer
169 	)
170 {
171 	register struct pstunit *up;
172 	struct refclockproc *pp;
173 
174 	pp = peer->procptr;
175 	up = pp->unitptr;
176 	if (-1 != pp->io.fd)
177 		io_closeclock(&pp->io);
178 	if (NULL != up)
179 		free(up);
180 }
181 
182 
183 /*
184  * pst_receive - receive data from the serial interface
185  */
186 static void
187 pst_receive(
188 	struct recvbuf *rbufp
189 	)
190 {
191 	register struct pstunit *up;
192 	struct refclockproc *pp;
193 	struct peer *peer;
194 	l_fp trtmp;
195 	u_long ltemp;
196 	char ampmchar;		/* AM/PM indicator */
197 	char daychar;		/* standard/daylight indicator */
198 	char junque[10];	/* "yy/dd/mm/" discard */
199 	char info[14];		/* "frdzycchhSSFT" clock info */
200 
201 	/*
202 	 * Initialize pointers and read the timecode and timestamp
203 	 */
204 	peer = rbufp->recv_peer;
205 	pp = peer->procptr;
206 	up = pp->unitptr;
207 	up->lastptr += refclock_gtlin(rbufp, up->lastptr, pp->a_lastcode
208 	    + BMAX - 2 - up->lastptr, &trtmp);
209 	*up->lastptr++ = ' ';
210 	*up->lastptr = '\0';
211 
212 	/*
213 	 * Note we get a buffer and timestamp for each <cr>, but only
214 	 * the first timestamp is retained.
215 	 */
216 	if (up->tcswitch == 0)
217 		pp->lastrec = trtmp;
218 	up->tcswitch++;
219 	pp->lencode = up->lastptr - pp->a_lastcode;
220 	if (up->tcswitch < 3)
221 		return;
222 
223 	/*
224 	 * We get down to business, check the timecode format and decode
225 	 * its contents. If the timecode has invalid length or is not in
226 	 * proper format, we declare bad format and exit.
227 	 */
228 	if (pp->lencode < LENPST) {
229 		refclock_report(peer, CEVNT_BADREPLY);
230 		return;
231 	}
232 
233 	/*
234 	 * Timecode format:
235 	 * "ahh:mm:ss.fffs yy/dd/mm/ddd frdzycchhSSFTttttuuxx"
236 	 */
237 	if (sscanf(pp->a_lastcode,
238 	    "%c%2d:%2d:%2d.%3ld%c %9s%3d%13s%4ld",
239 	    &ampmchar, &pp->hour, &pp->minute, &pp->second, &pp->nsec,
240 	    &daychar, junque, &pp->day, info, &ltemp) != 10) {
241 		refclock_report(peer, CEVNT_BADREPLY);
242 		return;
243 	}
244 	pp->nsec *= 1000000;
245 
246 	/*
247 	 * Decode synchronization, quality and last update. If
248 	 * unsynchronized, set the leap bits accordingly and exit. Once
249 	 * synchronized, the dispersion depends only on when the clock
250 	 * was last heard, which depends on the time since last update,
251 	 * as reported by the clock.
252 	 */
253 	if (info[9] != '8')
254 		pp->leap = LEAP_NOTINSYNC;
255 	if (info[12] == 'H')
256 		memcpy((char *)&pp->refid, WWVHREFID, 4);
257 	else
258 		memcpy((char *)&pp->refid, WWVREFID, 4);
259 	if (peer->stratum <= 1)
260 		peer->refid = pp->refid;
261 	if (ltemp == 0)
262 		pp->lastref = pp->lastrec;
263 	pp->disp = PST_PHI * ltemp * 60;
264 
265 	/*
266 	 * Process the new sample in the median filter and determine the
267 	 * timecode timestamp.
268 	 */
269 	if (!refclock_process(pp))
270 		refclock_report(peer, CEVNT_BADTIME);
271 	else if (peer->disp > MAXDISTANCE)
272 		refclock_receive(peer);
273 }
274 
275 
276 /*
277  * pst_poll - called by the transmit procedure
278  */
279 static void
280 pst_poll(
281 	int unit,
282 	struct peer *peer
283 	)
284 {
285 	register struct pstunit *up;
286 	struct refclockproc *pp;
287 
288 	/*
289 	 * Time to poll the clock. The PSTI/Traconex clock responds to a
290 	 * "QTQDQMT" by returning a timecode in the format specified
291 	 * above. Note there is no checking on state, since this may not
292 	 * be the only customer reading the clock. Only one customer
293 	 * need poll the clock; all others just listen in. If the clock
294 	 * becomes unreachable, declare a timeout and keep going.
295 	 */
296 	pp = peer->procptr;
297 	up = pp->unitptr;
298 	up->tcswitch = 0;
299 	up->lastptr = pp->a_lastcode;
300 	if (write(pp->io.fd, "QTQDQMT", 6) != 6)
301 		refclock_report(peer, CEVNT_FAULT);
302 	if (pp->coderecv == pp->codeproc) {
303 		refclock_report(peer, CEVNT_TIMEOUT);
304 		return;
305 	}
306 	refclock_receive(peer);
307 	record_clock_stats(&peer->srcadr, pp->a_lastcode);
308 #ifdef DEBUG
309 	if (debug)
310 		printf("pst: timecode %d %s\n", pp->lencode,
311 		    pp->a_lastcode);
312 #endif
313 	pp->polls++;
314 }
315 
316 #else
317 int refclock_pst_int;
318 #endif /* REFCLOCK */
319