contrib/ntp/libparse/clk_trimtsip.c

   1 /*
   2  * /src/NTP/ntp-4/libparse/clk_trimtsip.c,v 4.13 1999/11/28 09:13:51 kardel RELEASE_19991128_A
   3  *
   4  * clk_trimtsip.c,v 4.13 1999/11/28 09:13:51 kardel RELEASE_19991128_A
   5  *
   6  * Trimble TSIP support - CURRENTLY VERY MUCH UNDER CONSTRUCTION
   7  */
   8
   9 #ifdef HAVE_CONFIG_H
  10 # include <config.h>
  11 #endif
  12
  13 #if defined(REFCLOCK) && defined(CLOCK_PARSE) && defined(CLOCK_TRIMTSIP)
  14
  15 #include "ntp_syslog.h"
  16 #include "ntp_types.h"
  17 #include "ntp_fp.h"
  18 #include "ntp_unixtime.h"
  19 #include "ntp_calendar.h"
  20 #include "ntp_machine.h"
  21 #include "ntp_stdlib.h"
  22
  23 #include "parse.h"
  24
  25 #ifndef PARSESTREAM
  26 # include <stdio.h>
  27 #else
  28 # include "sys/parsestreams.h"
  29 #endif
  30
  31 #include "ascii.h"
  32 #include "binio.h"
  33 #include "ieee754io.h"
  34 #include "trimble.h"
  35
  36 /*
  37  * Trimble low level TSIP parser / time converter
  38  *
  39  * The receiver uses a serial message protocol called Trimble Standard
  40  * Interface Protocol (it can support others but this driver only supports
  41  * TSIP). Messages in this protocol have the following form:
  42  *
  43  * <DLE><id> ... <data> ... <DLE><ETX>
  44  *
  45  * Any bytes within the <data> portion of value 10 hex (<DLE>) are doubled
  46  * on transmission and compressed back to one on reception. Otherwise
  47  * the values of data bytes can be anything. The serial interface is RS-422
  48  * asynchronous using 9600 baud, 8 data bits with odd party (**note** 9 bits
  49  * in total!), and 1 stop bit. The protocol supports byte, integer, single,
  50  * and double datatypes. Integers are two bytes, sent most significant first.
  51  * Singles are IEEE754 single precision floating point numbers (4 byte) sent
  52  * sign & exponent first. Doubles are IEEE754 double precision floating point
  53  * numbers (8 byte) sent sign & exponent first.
  54  * The receiver supports a large set of messages, only a very small subset of
  55  * which is used here.
  56  *
  57  * From this module the following are recognised:
  58  *
  59  *  ID    Description
  60  *
  61  *  41    GPS Time
  62  *  46    Receiver health
  63  *  4F    UTC correction data (used to get leap second warnings)
  64  *
  65  * All others are accepted but ignored for time conversion - they are passed up to higher layers.
  66  *
  67  */
  68
  69 static offsets_t trim_offsets = { 0, 1, 2, 3, 4, 5, 6, 7 };
  70
  71 struct trimble
  72 {
  73         u_char  t_in_pkt;       /* first DLE received */
  74         u_char  t_dle;          /* subsequent DLE received */
  75         u_short t_week;         /* GPS week */
  76         u_short t_weekleap;     /* GPS week of next/last week */
  77         u_short t_dayleap;      /* day in week */
  78         u_short t_gpsutc;       /* GPS - UTC offset */
  79         u_short t_gpsutcleap;   /* offset at next/last leap */
  80         u_char  t_operable;     /* receiver feels OK */
  81         u_char  t_mode;         /* actual operating mode */
  82         u_char  t_leap;         /* possible leap warning */
  83         u_char  t_utcknown;     /* utc offset known */
  84 };
  85
  86 #define STATUS_BAD    0         /* BAD or UNINITIALIZED receiver status */
  87 #define STATUS_UNSAFE 1         /* not enough receivers for full precision */
  88 #define STATUS_SYNC   2         /* enough information for good operation */
  89
  90 static unsigned long inp_tsip P((parse_t *, unsigned int, timestamp_t *));
  91 static unsigned long cvt_trimtsip P((unsigned char *, int, struct format *, clocktime_t *, void *));
  92
  93 struct clockformat clock_trimtsip =
  94 {
  95         inp_tsip,               /* Trimble TSIP input handler */
  96         cvt_trimtsip,           /* Trimble TSIP conversion */
  97         pps_one,                /* easy PPS monitoring */
  98         0,                      /* no configuration data */
  99         "Trimble TSIP",
 100         400,                    /* input buffer */
 101         sizeof(struct trimble)  /* private data */
 102 };
 103
 104 #define ADDSECOND       0x01
 105 #define DELSECOND       0x02
 106
 107 static unsigned long
 108 inp_tsip(
 109          parse_t      *parseio,
 110          unsigned int ch,
 111          timestamp_t  *tstamp
 112         )
 113 {
 114         struct trimble *t = (struct trimble *)parseio->parse_pdata;
 115
 116         if (!t)
 117             return PARSE_INP_SKIP;              /* local data not allocated - sigh! */
 118
 119         if (!t->t_in_pkt && ch != DLE) {
 120                 /* wait for start of packet */
 121                 return PARSE_INP_SKIP;
 122         }
 123
 124         if ((parseio->parse_index >= (parseio->parse_dsize - 2)) ||
 125             (parseio->parse_dtime.parse_msglen >= (sizeof(parseio->parse_dtime.parse_msg) - 2)))
 126                 {               /* OVERFLOW - DROP! */
 127                         t->t_in_pkt = t->t_dle = 0;
 128                         parseio->parse_index = 0;
 129                         parseio->parse_dtime.parse_msglen = 0;
 130                 return PARSE_INP_SKIP;
 131         }
 132
 133         switch (ch) {
 134             case DLE:
 135                 if (!t->t_in_pkt) {
 136                         t->t_dle = 0;
 137                         t->t_in_pkt = 1;
 138                         parseio->parse_index = 0;
 139                         parseio->parse_data[parseio->parse_index++] = ch;
 140                         parseio->parse_dtime.parse_msglen = 0;
 141                         parseio->parse_dtime.parse_msg[parseio->parse_dtime.parse_msglen++] = ch;
 142                         parseio->parse_dtime.parse_stime = *tstamp; /* pick up time stamp at packet start */
 143                 } else if (t->t_dle) {
 144                         /* Double DLE -> insert a DLE */
 145                         t->t_dle = 0;
 146                         parseio->parse_data[parseio->parse_index++] = DLE;
 147                         parseio->parse_dtime.parse_msg[parseio->parse_dtime.parse_msglen++] = DLE;
 148                 } else
 149                     t->t_dle = 1;
 150                 break;
 151
 152             case ETX:
 153                 if (t->t_dle) {
 154                         /* DLE,ETX -> end of packet */
 155                         parseio->parse_data[parseio->parse_index++] = DLE;
 156                         parseio->parse_data[parseio->parse_index] = ch;
 157                         parseio->parse_ldsize = parseio->parse_index+1;
 158                         memcpy(parseio->parse_ldata, parseio->parse_data, parseio->parse_ldsize);
 159                         parseio->parse_dtime.parse_msg[parseio->parse_dtime.parse_msglen++] = DLE;
 160                         parseio->parse_dtime.parse_msg[parseio->parse_dtime.parse_msglen++] = ch;
 161                         t->t_in_pkt = t->t_dle = 0;
 162                         return PARSE_INP_TIME|PARSE_INP_DATA;
 163                 }
 164
 165             default:            /* collect data */
 166                 t->t_dle = 0;
 167                 parseio->parse_data[parseio->parse_index++] = ch;
 168                 parseio->parse_dtime.parse_msg[parseio->parse_dtime.parse_msglen++] = ch;
 169         }
 170
 171   return PARSE_INP_SKIP;
 172 }
 173
 174 static int
 175 getshort(
 176          unsigned char *p
 177          )
 178 {
 179         return get_msb_short(&p);
 180 }
 181
 182 /*
 183  * cvt_trimtsip
 184  *
 185  * convert TSIP type format
 186  */
 187 static unsigned long
 188 cvt_trimtsip(
 189              unsigned char *buffer,
 190              int            size,
 191              struct format *format,
 192              clocktime_t   *clock_time,
 193              void          *local
 194              )
 195 {
 196         register struct trimble *t = (struct trimble *)local; /* get local data space */
 197 #define mb(_X_) (buffer[2+(_X_)]) /* shortcut for buffer access */
 198         register u_char cmd;
 199
 200         clock_time->flags = 0;
 201
 202         if (!t) {
 203                 return CVT_NONE;                /* local data not allocated - sigh! */
 204         }
 205
 206         if ((size < 4) ||
 207             (buffer[0]      != DLE) ||
 208             (buffer[size-1] != ETX) ||
 209             (buffer[size-2] != DLE))
 210         {
 211                 printf("TRIMBLE BAD packet, size %d:\n", size);
 212                 return CVT_NONE;
 213         }
 214         else
 215         {
 216                 unsigned char *bp;
 217                 cmd = buffer[1];
 218
 219                     switch(cmd)
 220                     {
 221                     case CMD_RCURTIME:
 222                             {                   /* GPS time */
 223                                     l_fp secs;
 224                                     int   week = getshort((unsigned char *)&mb(4));
 225                                     l_fp utcoffset;
 226                                     l_fp gpstime;
 227
 228                                     bp = &mb(0);
 229                                     if (fetch_ieee754(&bp, IEEE_SINGLE, &secs, trim_offsets) != IEEE_OK)
 230                                             return CVT_FAIL|CVT_BADFMT;
 231
 232                                     if ((secs.l_i <= 0) ||
 233                                         (t->t_utcknown == 0))
 234                                     {
 235                                             clock_time->flags = PARSEB_POWERUP;
 236                                             return CVT_OK;
 237                                     }
 238                                     if (week < 990) {
 239                                             week += 1024;
 240                                     }
 241
 242                                     /* time OK */
 243
 244                                     /* fetch UTC offset */
 245                                     bp = &mb(6);
 246                                     if (fetch_ieee754(&bp, IEEE_SINGLE, &utcoffset, trim_offsets) != IEEE_OK)
 247                                             return CVT_FAIL|CVT_BADFMT;
 248
 249                                     L_SUB(&secs, &utcoffset); /* adjust GPS time to UTC time */
 250
 251                                     gpstolfp((unsigned short)week, (unsigned short)0,
 252                                              secs.l_ui, &gpstime);
 253
 254                                     gpstime.l_uf = secs.l_uf;
 255
 256                                     clock_time->utctime = gpstime.l_ui - JAN_1970;
 257
 258                                     TSFTOTVU(gpstime.l_uf, clock_time->usecond);
 259
 260                                     if (t->t_leap == ADDSECOND)
 261                                         clock_time->flags |= PARSEB_LEAPADD;
 262
 263                                     if (t->t_leap == DELSECOND)
 264                                         clock_time->flags |= PARSEB_LEAPDEL;
 265
 266                                     switch (t->t_operable)
 267                                       {
 268                                       case STATUS_SYNC:
 269                                         clock_time->flags &= ~(PARSEB_POWERUP|PARSEB_NOSYNC);
 270                                         break;
 271
 272                                       case STATUS_UNSAFE:
 273                                         clock_time->flags |= PARSEB_NOSYNC;
 274                                         break;
 275
 276                                       case STATUS_BAD:
 277                                         clock_time->flags |= PARSEB_NOSYNC|PARSEB_POWERUP;
 278                                         break;
 279                                       }
 280
 281                                     if (t->t_mode == 0)
 282                                             clock_time->flags |= PARSEB_POSITION;
 283
 284                                     clock_time->flags |= PARSEB_S_LEAP|PARSEB_S_POSITION;
 285
 286                                     return CVT_OK;
 287
 288                             } /* case 0x41 */
 289
 290                     case CMD_RRECVHEALTH:
 291                             {
 292                                     /* TRIMBLE health */
 293                                     u_char status = mb(0);
 294
 295                                     switch (status)
 296                                     {
 297                                       case 0x00: /* position fixes */
 298                                         t->t_operable = STATUS_SYNC;
 299                                         break;
 300
 301                                       case 0x09: /* 1 satellite */
 302                                       case 0x0A: /* 2 satellites */
 303                                       case 0x0B: /* 3 satellites */
 304                                         t->t_operable = STATUS_UNSAFE;
 305                                         break;
 306
 307                                       default:
 308                                         t->t_operable = STATUS_BAD;
 309                                         break;
 310                                     }
 311                                     t->t_mode = status;
 312                             }
 313                             break;
 314
 315                     case CMD_RUTCPARAM:
 316                             {
 317                                     l_fp t0t;
 318                                     unsigned char *lbp;
 319
 320                                     /* UTC correction data - derive a leap warning */
 321                                     int tls   = t->t_gpsutc     = getshort((unsigned char *)&mb(12)); /* current leap correction (GPS-UTC) */
 322                                     int tlsf  = t->t_gpsutcleap = getshort((unsigned char *)&mb(24)); /* new leap correction */
 323
 324                                     t->t_weekleap   = getshort((unsigned char *)&mb(20)); /* week no of leap correction */
 325                                     if (t->t_weekleap < 990)
 326                                       t->t_weekleap += 1024;
 327
 328                                     t->t_dayleap    = getshort((unsigned char *)&mb(22)); /* day in week of leap correction */
 329                                     t->t_week = getshort((unsigned char *)&mb(18)); /* current week no */
 330                                     if (t->t_week < 990)
 331                                       t->t_week += 1024;
 332
 333                                     lbp = (unsigned char *)&mb(14); /* last update time */
 334                                     if (fetch_ieee754(&lbp, IEEE_SINGLE, &t0t, trim_offsets) != IEEE_OK)
 335                                             return CVT_FAIL|CVT_BADFMT;
 336
 337                                     t->t_utcknown = t0t.l_ui != 0;
 338
 339                                     if ((t->t_utcknown) && /* got UTC information */
 340                                         (tlsf != tls)   && /* something will change */
 341                                         ((t->t_weekleap - t->t_week) < 5)) /* and close in the future */
 342                                     {
 343                                             /* generate a leap warning */
 344                                             if (tlsf > tls)
 345                                                 t->t_leap = ADDSECOND;
 346                                             else
 347                                                 t->t_leap = DELSECOND;
 348                                     }
 349                                     else
 350                                     {
 351                                             t->t_leap = 0;
 352                                     }
 353                             }
 354                             break;
 355
 356                     default:
 357                             /* it's validly formed, but we don't care about it! */
 358                             break;
 359                 }
 360         }
 361         return CVT_SKIP;
 362 }
 363
 364 #else /* not (REFCLOCK && CLOCK_PARSE && CLOCK_TRIMTSIP && !PARSESTREAM) */
 365 int clk_trimtsip_bs;
 366 #endif /* not (REFCLOCK && CLOCK_PARSE && CLOCK_TRIMTSIP && !PARSESTREAM) */
 367
 368 /*
 369  * History:
 370  *
 371  * clk_trimtsip.c,v
 372  * Revision 4.13  1999/11/28 09:13:51  kardel
 373  * RECON_4_0_98F
 374  *
 375  * Revision 4.12  1999/02/28 13:00:08  kardel
 376  * *** empty log message ***
 377  *
 378  * Revision 4.11  1999/02/28 11:47:54  kardel
 379  * (struct trimble): new member t_utcknown
 380  * (cvt_trimtsip): fixed status monitoring, bad receiver states are
 381  * now recognized
 382  *
 383  * Revision 4.10  1999/02/27 15:57:15  kardel
 384  * use mmemcpy instead of bcopy
 385  *
 386  * Revision 4.9  1999/02/21 12:17:42  kardel
 387  * 4.91f reconcilation
 388  *
 389  * Revision 4.8  1998/11/15 20:27:58  kardel
 390  * Release 4.0.73e13 reconcilation
 391  *
 392  * Revision 4.7  1998/08/16 18:49:20  kardel
 393  * (cvt_trimtsip): initial kernel capable version (no more floats)
 394  * (clock_trimtsip =): new format name
 395  *
 396  * Revision 4.6  1998/08/09 22:26:05  kardel
 397  * Trimble TSIP support
 398  *
 399  * Revision 4.5  1998/08/02 10:37:05  kardel
 400  * working TSIP parser
 401  *
 402  * Revision 4.4  1998/06/28 16:50:40  kardel
 403  * (getflt): fixed ENDIAN issue
 404  * (getdbl): fixed ENDIAN issue
 405  * (getint): use get_msb_short()
 406  * (cvt_trimtsip): use gpstolfp() for conversion
 407  *
 408  * Revision 4.3  1998/06/13 12:07:31  kardel
 409  * fix SYSV clock name clash
 410  *
 411  * Revision 4.2  1998/06/12 15:22:30  kardel
 412  * fix prototypes
 413  *
 414  * Revision 4.1  1998/05/24 09:39:54  kardel
 415  * implementation of the new IO handling model
 416  *
 417  * Revision 4.0  1998/04/10 19:45:32  kardel
 418  * Start 4.0 release version numbering
 419  *
 420  * from V3 1.8 loginfo deleted 1998/04/11 kardel
 421  */