1 /*        $NetBSD: clk_trimtsip.c,v 1.8 2024/08/18 20:47:17 christos Exp $      */
2 
3 /*
4  * /src/NTP/REPOSITORY/ntp4-dev/libparse/clk_trimtsip.c,v 4.19 2009/11/01 10:47:49 kardel RELEASE_20091101_A
5  *
6  * clk_trimtsip.c,v 4.19 2009/11/01 10:47:49 kardel RELEASE_20091101_A
7  *
8  * Trimble TSIP support
9  * Thanks to Sven Dietrich for providing test hardware
10  *
11  * Copyright (c) 1995-2009 by Frank Kardel <kardel <AT> ntp.org>
12  * Copyright (c) 1989-1994 by Frank Kardel, Friedrich-Alexander Universitaet Erlangen-Nuernberg, Germany
13  *
14  * Redistribution and use in source and binary forms, with or without
15  * modification, are permitted provided that the following conditions
16  * are met:
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  * 2. Redistributions in binary form must reproduce the above copyright
20  *    notice, this list of conditions and the following disclaimer in the
21  *    documentation and/or other materials provided with the distribution.
22  * 3. Neither the name of the author nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  */
39 
40 #ifdef HAVE_CONFIG_H
41 # include <config.h>
42 #endif
43 
44 #if defined(REFCLOCK) && defined(CLOCK_PARSE) && defined(CLOCK_TRIMTSIP)
45 
46 #include "ntp_syslog.h"
47 #include "ntp_types.h"
48 #include "ntp_fp.h"
49 #include "timevalops.h"
50 #include "ntp_calendar.h"
51 #include "ntp_machine.h"
52 #include "ntp_stdlib.h"
53 
54 #include "parse.h"
55 
56 #ifndef PARSESTREAM
57 # include <stdio.h>
58 #else
59 # include "sys/parsestreams.h"
60 #endif
61 
62 #include "ascii.h"
63 #include "binio.h"
64 #include "ieee754io.h"
65 #include "trimble.h"
66 
67 /*
68  * Trimble low level TSIP parser / time converter
69  *
70  * The receiver uses a serial message protocol called Trimble Standard
71  * Interface Protocol (it can support others but this driver only supports
72  * TSIP). Messages in this protocol have the following form:
73  *
74  * <DLE><id> ... <data> ... <DLE><ETX>
75  *
76  * Any bytes within the <data> portion of value 10 hex (<DLE>) are doubled
77  * on transmission and compressed back to one on reception. Otherwise
78  * the values of data bytes can be anything. The serial interface is RS-422
79  * asynchronous using 9600 baud, 8 data bits with odd party (**note** 9 bits
80  * in total!), and 1 stop bit. The protocol supports byte, integer, single,
81  * and double datatypes. Integers are two bytes, sent most significant first.
82  * Singles are IEEE754 single precision floating point numbers (4 byte) sent
83  * sign & exponent first. Doubles are IEEE754 double precision floating point
84  * numbers (8 byte) sent sign & exponent first.
85  * The receiver supports a large set of messages, only a very small subset of
86  * which is used here.
87  *
88  * From this module the following are recognised:
89  *
90  *  ID    Description
91  *
92  *  41    GPS Time
93  *  46    Receiver health
94  *  4F    UTC correction data (used to get leap second warnings)
95  *
96  * All others are accepted but ignored for time conversion - they are passed up to higher layers.
97  *
98  */
99 
100 static offsets_t trim_offsets = { 0, 1, 2, 3, 4, 5, 6, 7 };
101 
102 struct trimble
103 {
104           u_char  t_in_pkt;   /* first DLE received */
105           u_char  t_dle;                /* subsequent DLE received */
106           u_short t_week;               /* GPS week */
107           u_short t_weekleap; /* GPS week of next/last week */
108           u_short t_dayleap;  /* day in week */
109           u_short t_gpsutc;   /* GPS - UTC offset */
110           u_short t_gpsutcleap;         /* offset at next/last leap */
111           u_char  t_operable; /* receiver feels OK */
112           u_char  t_mode;               /* actual operating mode */
113           u_char  t_leap;               /* possible leap warning */
114         u_char  t_utcknown;   /* utc offset known */
115 };
116 
117 #define STATUS_BAD    0                 /* BAD or UNINITIALIZED receiver status */
118 #define STATUS_UNSAFE 1                 /* not enough receivers for full precision */
119 #define STATUS_SYNC   2                 /* enough information for good operation */
120 
121 static unsigned long inp_tsip (parse_t *, char, timestamp_t *);
122 static unsigned long cvt_trimtsip (unsigned char *, int, struct format *, clocktime_t *, void *);
123 
124 struct clockformat clock_trimtsip =
125 {
126           inp_tsip,           /* Trimble TSIP input handler */
127           cvt_trimtsip,                 /* Trimble TSIP conversion */
128           pps_one,            /* easy PPS monitoring */
129           0,                            /* no configuration data */
130           "Trimble TSIP",
131           400,                          /* input buffer */
132           sizeof(struct trimble)        /* private data */
133 };
134 
135 #define ADDSECOND   0x01
136 #define DELSECOND   0x02
137 
138 static unsigned long
inp_tsip(parse_t * parseio,char ch,timestamp_t * tstamp)139 inp_tsip(
140            parse_t      *parseio,
141            char         ch,
142            timestamp_t  *tstamp
143           )
144 {
145           struct trimble *t = (struct trimble *)parseio->parse_pdata;
146 
147           if (!t)
148               return PARSE_INP_SKIP;              /* local data not allocated - sigh! */
149 
150           if (!t->t_in_pkt && ch != DLE) {
151                     /* wait for start of packet */
152                     return PARSE_INP_SKIP;
153           }
154 
155           if ((parseio->parse_index >= (parseio->parse_dsize - 2)) ||
156               (parseio->parse_dtime.parse_msglen >= (sizeof(parseio->parse_dtime.parse_msg) - 2)))
157                     {                   /* OVERFLOW - DROP! */
158                               t->t_in_pkt = t->t_dle = 0;
159                               parseio->parse_index = 0;
160                               parseio->parse_dtime.parse_msglen = 0;
161                     return PARSE_INP_SKIP;
162           }
163 
164           switch (ch) {
165               case DLE:
166                     if (!t->t_in_pkt) {
167                               t->t_dle = 0;
168                               t->t_in_pkt = 1;
169                               parseio->parse_index = 0;
170                               parseio->parse_data[parseio->parse_index++] = ch;
171                               parseio->parse_dtime.parse_msglen = 0;
172                               parseio->parse_dtime.parse_msg[parseio->parse_dtime.parse_msglen++] = ch;
173                               parseio->parse_dtime.parse_stime = *tstamp; /* pick up time stamp at packet start */
174                     } else if (t->t_dle) {
175                               /* Double DLE -> insert a DLE */
176                               t->t_dle = 0;
177                               parseio->parse_data[parseio->parse_index++] = DLE;
178                               parseio->parse_dtime.parse_msg[parseio->parse_dtime.parse_msglen++] = DLE;
179                     } else
180                         t->t_dle = 1;
181                     break;
182 
183               case ETX:
184                     if (t->t_dle) {
185                               /* DLE,ETX -> end of packet */
186                               parseio->parse_data[parseio->parse_index++] = DLE;
187                               parseio->parse_data[parseio->parse_index] = ch;
188                               parseio->parse_ldsize = (u_short) (parseio->parse_index + 1);
189                               memcpy(parseio->parse_ldata, parseio->parse_data, parseio->parse_ldsize);
190                               parseio->parse_dtime.parse_msg[parseio->parse_dtime.parse_msglen++] = DLE;
191                               parseio->parse_dtime.parse_msg[parseio->parse_dtime.parse_msglen++] = ch;
192                               t->t_in_pkt = t->t_dle = 0;
193                               return PARSE_INP_TIME|PARSE_INP_DATA;
194                     }
195                     /*FALLTHROUGH*/
196 
197               default:                  /* collect data */
198                     t->t_dle = 0;
199                     parseio->parse_data[parseio->parse_index++] = ch;
200                     parseio->parse_dtime.parse_msg[parseio->parse_dtime.parse_msglen++] = ch;
201           }
202 
203   return PARSE_INP_SKIP;
204 }
205 
206 static short
getshort(unsigned char * p)207 getshort(
208            unsigned char *p
209            )
210 {
211           return (short) get_msb_short(&p);
212 }
213 
214 /*
215  * cvt_trimtsip
216  *
217  * convert TSIP type format
218  */
219 static unsigned long
cvt_trimtsip(unsigned char * buffer,int size,struct format * format,clocktime_t * clock_time,void * local)220 cvt_trimtsip(
221                unsigned char *buffer,
222                int            size,
223                struct format *format,
224                clocktime_t   *clock_time,
225                void          *local
226                )
227 {
228         register struct trimble *t = (struct trimble *)local; /* get local data space */
229 #define mb(_X_) (buffer[2+(_X_)]) /* shortcut for buffer access */
230           register u_char cmd;
231 
232           clock_time->flags = 0;
233 
234           if (!t) {
235                     return CVT_NONE;              /* local data not allocated - sigh! */
236           }
237 
238           if ((size < 4) ||
239               (buffer[0]      != DLE) ||
240               (buffer[size-1] != ETX) ||
241               (buffer[size-2] != DLE))
242           {
243                     printf("TRIMBLE BAD packet, size %d:\n", size);
244                     return CVT_NONE;
245           }
246           else
247           {
248                     unsigned char *bp;
249                     cmd = buffer[1];
250 
251                         switch(cmd)
252                         {
253                         case CMD_RCURTIME:
254                                   {                         /* GPS time */
255                                             l_fp  secs;
256                                             u_int week = getshort((unsigned char *)&mb(4));
257                                             l_fp  utcoffset;
258                                             l_fp  gpstime;
259 
260                                             bp = &mb(0);
261                                             if (fetch_ieee754(&bp, IEEE_SINGLE, &secs, trim_offsets) != IEEE_OK)
262                                                       return CVT_FAIL|CVT_BADFMT;
263 
264                                             if ((secs.l_i <= 0) ||
265                                                   (t->t_utcknown == 0))
266                                             {
267                                                       clock_time->flags = PARSEB_POWERUP;
268                                                       return CVT_OK;
269                                             }
270                                             week = basedate_expand_gpsweek(week);
271 
272                                             /* time OK */
273 
274                                             /* fetch UTC offset */
275                                             bp = &mb(6);
276                                             if (fetch_ieee754(&bp, IEEE_SINGLE, &utcoffset, trim_offsets) != IEEE_OK)
277                                                       return CVT_FAIL|CVT_BADFMT;
278 
279                                             L_SUB(&secs, &utcoffset); /* adjust GPS time to UTC time */
280 
281                                             gpstolfp((unsigned short)week, (unsigned short)0,
282                                                        secs.l_ui, &gpstime);
283 
284                                             gpstime.l_uf = secs.l_uf;
285 
286                                             clock_time->utctime = gpstime.l_ui - JAN_1970;
287 
288                                             TSFTOTVU(gpstime.l_uf, clock_time->usecond);
289 
290                                             if (t->t_leap == ADDSECOND)
291                                                   clock_time->flags |= PARSEB_LEAPADD;
292 
293                                             if (t->t_leap == DELSECOND)
294                                                   clock_time->flags |= PARSEB_LEAPDEL;
295 
296                                             switch (t->t_operable)
297                                               {
298                                               case STATUS_SYNC:
299                                                   clock_time->flags &= ~(PARSEB_POWERUP|PARSEB_NOSYNC);
300                                                   break;
301 
302                                               case STATUS_UNSAFE:
303                                                   clock_time->flags |= PARSEB_NOSYNC;
304                                                   break;
305 
306                                               case STATUS_BAD:
307                                                   clock_time->flags |= PARSEB_NOSYNC|PARSEB_POWERUP;
308                                                   break;
309                                               }
310 
311                                             if (t->t_mode == 0)
312                                                       clock_time->flags |= PARSEB_POSITION;
313 
314                                             clock_time->flags |= PARSEB_S_LEAP|PARSEB_S_POSITION;
315 
316                                             return CVT_OK;
317 
318                                   } /* case 0x41 */
319 
320                         case CMD_RRECVHEALTH:
321                                   {
322                                             /* TRIMBLE health */
323                                             u_char status = mb(0);
324 
325                                             switch (status)
326                                             {
327                                               case 0x00: /* position fixes */
328                                                   t->t_operable = STATUS_SYNC;
329                                                   break;
330 
331                                               case 0x09: /* 1 satellite */
332                                               case 0x0A: /* 2 satellites */
333                                               case 0x0B: /* 3 satellites */
334                                                   t->t_operable = STATUS_UNSAFE;
335                                                   break;
336 
337                                               default:
338                                                   t->t_operable = STATUS_BAD;
339                                                   break;
340                                             }
341                                             t->t_mode = status;
342                                   }
343                                   break;
344 
345                         case CMD_RUTCPARAM:
346                                   {
347                                           l_fp t0t;
348                                             unsigned char *lbp;
349 
350                                             /* UTC correction data - derive a leap warning */
351                                             int tls   = t->t_gpsutc     = (u_short) getshort((unsigned char *)&mb(12)); /* current leap correction (GPS-UTC) */
352                                             int tlsf  = t->t_gpsutcleap = (u_short) getshort((unsigned char *)&mb(24)); /* new leap correction */
353 
354                                             t->t_weekleap   = basedate_expand_gpsweek(
355                                                   (u_short) getshort((unsigned char *)&mb(20))); /* week no of leap correction */
356 
357                                             t->t_dayleap    = (u_short) getshort((unsigned char *)&mb(22)); /* day in week of leap correction */
358                                             t->t_week = basedate_expand_gpsweek(
359                                                   (u_short) getshort((unsigned char *)&mb(18))); /* current week no */
360 
361                                             lbp = (unsigned char *)&mb(14); /* last update time */
362                                             if (fetch_ieee754(&lbp, IEEE_SINGLE, &t0t, trim_offsets) != IEEE_OK)
363                                                       return CVT_FAIL|CVT_BADFMT;
364 
365                                             t->t_utcknown = t0t.l_ui != 0;
366 
367                                             if ((t->t_utcknown) && /* got UTC information */
368                                                   (tlsf != tls)   && /* something will change */
369                                                   ((t->t_weekleap - t->t_week) < 5)) /* and close in the future */
370                                             {
371                                                       /* generate a leap warning */
372                                                       if (tlsf > tls)
373                                                             t->t_leap = ADDSECOND;
374                                                       else
375                                                             t->t_leap = DELSECOND;
376                                             }
377                                             else
378                                             {
379                                                       t->t_leap = 0;
380                                             }
381                                   }
382                                   break;
383 
384                         default:
385                                   /* it's validly formed, but we don't care about it! */
386                                   break;
387                     }
388           }
389           return CVT_SKIP;
390 }
391 
392 #else /* not (REFCLOCK && CLOCK_PARSE && CLOCK_TRIMTSIP && !PARSESTREAM) */
393 NONEMPTY_TRANSLATION_UNIT
394 #endif /* not (REFCLOCK && CLOCK_PARSE && CLOCK_TRIMTSIP && !PARSESTREAM) */
395 
396 /*
397  * History:
398  *
399  * clk_trimtsip.c,v
400  * Revision 4.19  2009/11/01 10:47:49  kardel
401  * de-P()
402  *
403  * Revision 4.18  2009/11/01 08:46:46  kardel
404  * clarify case FALLTHROUGH
405  *
406  * Revision 4.17  2005/04/16 17:32:10  kardel
407  * update copyright
408  *
409  * Revision 4.16  2004/11/14 15:29:41  kardel
410  * support PPSAPI, upgrade Copyright to Berkeley style
411  *
412  * Revision 4.13  1999/11/28 09:13:51  kardel
413  * RECON_4_0_98F
414  *
415  * Revision 4.12  1999/02/28 13:00:08  kardel
416  * *** empty log message ***
417  *
418  * Revision 4.11  1999/02/28 11:47:54  kardel
419  * (struct trimble): new member t_utcknown
420  * (cvt_trimtsip): fixed status monitoring, bad receiver states are
421  * now recognized
422  *
423  * Revision 4.10  1999/02/27 15:57:15  kardel
424  * use mmemcpy instead of bcopy
425  *
426  * Revision 4.9  1999/02/21 12:17:42  kardel
427  * 4.91f reconcilation
428  *
429  * Revision 4.8  1998/11/15 20:27:58  kardel
430  * Release 4.0.73e13 reconcilation
431  *
432  * Revision 4.7  1998/08/16 18:49:20  kardel
433  * (cvt_trimtsip): initial kernel capable version (no more floats)
434  * (clock_trimtsip =): new format name
435  *
436  * Revision 4.6  1998/08/09 22:26:05  kardel
437  * Trimble TSIP support
438  *
439  * Revision 4.5  1998/08/02 10:37:05  kardel
440  * working TSIP parser
441  *
442  * Revision 4.4  1998/06/28 16:50:40  kardel
443  * (getflt): fixed ENDIAN issue
444  * (getdbl): fixed ENDIAN issue
445  * (getint): use get_msb_short()
446  * (cvt_trimtsip): use gpstolfp() for conversion
447  *
448  * Revision 4.3  1998/06/13 12:07:31  kardel
449  * fix SYSV clock name clash
450  *
451  * Revision 4.2  1998/06/12 15:22:30  kardel
452  * fix prototypes
453  *
454  * Revision 4.1  1998/05/24 09:39:54  kardel
455  * implementation of the new IO handling model
456  *
457  * Revision 4.0  1998/04/10 19:45:32  kardel
458  * Start 4.0 release version numbering
459  *
460  * from V3 1.8 loginfo deleted 1998/04/11 kardel
461  */
462