/contrib/ntp/libparse/clk_rawdcf.c
https://bitbucket.org/freebsd/freebsd-head/ · C · 658 lines · 406 code · 73 blank · 179 comment · 56 complexity · 202554d133a1a281aadeec284a471b69 MD5 · raw file
- /*
- * /src/NTP/REPOSITORY/ntp4-dev/libparse/clk_rawdcf.c,v 4.18 2006/06/22 18:40:01 kardel RELEASE_20060622_A
- *
- * clk_rawdcf.c,v 4.18 2006/06/22 18:40:01 kardel RELEASE_20060622_A
- *
- * Raw DCF77 pulse clock support
- *
- * Copyright (c) 1995-2006 by Frank Kardel <kardel <AT> ntp.org>
- * Copyright (c) 1989-1994 by Frank Kardel, Friedrich-Alexander Universität Erlangen-Nürnberg, Germany
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. Neither the name of the author nor the names of its contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- *
- */
- #ifdef HAVE_CONFIG_H
- # include <config.h>
- #endif
- #if defined(REFCLOCK) && defined(CLOCK_PARSE) && defined(CLOCK_RAWDCF)
- #include "ntp_fp.h"
- #include "ntp_unixtime.h"
- #include "ntp_calendar.h"
- #include "parse.h"
- #ifdef PARSESTREAM
- # include <sys/parsestreams.h>
- #endif
- #ifndef PARSEKERNEL
- # include "ntp_stdlib.h"
- #endif
- /*
- * DCF77 raw time code
- *
- * From "Zur Zeit", Physikalisch-Technische Bundesanstalt (PTB), Braunschweig
- * und Berlin, Maerz 1989
- *
- * Timecode transmission:
- * AM:
- * time marks are send every second except for the second before the
- * next minute mark
- * time marks consist of a reduction of transmitter power to 25%
- * of the nominal level
- * the falling edge is the time indication (on time)
- * time marks of a 100ms duration constitute a logical 0
- * time marks of a 200ms duration constitute a logical 1
- * FM:
- * see the spec. (basically a (non-)inverted psuedo random phase shift)
- *
- * Encoding:
- * Second Contents
- * 0 - 10 AM: free, FM: 0
- * 11 - 14 free
- * 15 R - alternate antenna
- * 16 A1 - expect zone change (1 hour before)
- * 17 - 18 Z1,Z2 - time zone
- * 0 0 illegal
- * 0 1 MEZ (MET)
- * 1 0 MESZ (MED, MET DST)
- * 1 1 illegal
- * 19 A2 - expect leap insertion/deletion (1 hour before)
- * 20 S - start of time code (1)
- * 21 - 24 M1 - BCD (lsb first) Minutes
- * 25 - 27 M10 - BCD (lsb first) 10 Minutes
- * 28 P1 - Minute Parity (even)
- * 29 - 32 H1 - BCD (lsb first) Hours
- * 33 - 34 H10 - BCD (lsb first) 10 Hours
- * 35 P2 - Hour Parity (even)
- * 36 - 39 D1 - BCD (lsb first) Days
- * 40 - 41 D10 - BCD (lsb first) 10 Days
- * 42 - 44 DW - BCD (lsb first) day of week (1: Monday -> 7: Sunday)
- * 45 - 49 MO - BCD (lsb first) Month
- * 50 MO0 - 10 Months
- * 51 - 53 Y1 - BCD (lsb first) Years
- * 54 - 57 Y10 - BCD (lsb first) 10 Years
- * 58 P3 - Date Parity (even)
- * 59 - usually missing (minute indication), except for leap insertion
- */
- static u_long pps_rawdcf P((parse_t *, int, timestamp_t *));
- static u_long cvt_rawdcf P((unsigned char *, int, struct format *, clocktime_t *, void *));
- static u_long inp_rawdcf P((parse_t *, unsigned int, timestamp_t *));
- typedef struct last_tcode {
- time_t tcode; /* last converted time code */
- } last_tcode_t;
- #define BUFFER_MAX 61
- clockformat_t clock_rawdcf =
- {
- inp_rawdcf, /* DCF77 input handling */
- cvt_rawdcf, /* raw dcf input conversion */
- pps_rawdcf, /* examining PPS information */
- 0, /* no private configuration data */
- "RAW DCF77 Timecode", /* direct decoding / time synthesis */
- BUFFER_MAX, /* bit buffer */
- sizeof(last_tcode_t)
- };
- static struct dcfparam
- {
- unsigned char *onebits;
- unsigned char *zerobits;
- } dcfparameter =
- {
- (unsigned char *)"###############RADMLS1248124P124812P1248121241248112481248P??", /* 'ONE' representation */
- (unsigned char *)"--------------------s-------p------p----------------------p__" /* 'ZERO' representation */
- };
- static struct rawdcfcode
- {
- char offset; /* start bit */
- } rawdcfcode[] =
- {
- { 0 }, { 15 }, { 16 }, { 17 }, { 19 }, { 20 }, { 21 }, { 25 }, { 28 }, { 29 },
- { 33 }, { 35 }, { 36 }, { 40 }, { 42 }, { 45 }, { 49 }, { 50 }, { 54 }, { 58 }, { 59 }
- };
- #define DCF_M 0
- #define DCF_R 1
- #define DCF_A1 2
- #define DCF_Z 3
- #define DCF_A2 4
- #define DCF_S 5
- #define DCF_M1 6
- #define DCF_M10 7
- #define DCF_P1 8
- #define DCF_H1 9
- #define DCF_H10 10
- #define DCF_P2 11
- #define DCF_D1 12
- #define DCF_D10 13
- #define DCF_DW 14
- #define DCF_MO 15
- #define DCF_MO0 16
- #define DCF_Y1 17
- #define DCF_Y10 18
- #define DCF_P3 19
- static struct partab
- {
- char offset; /* start bit of parity field */
- } partab[] =
- {
- { 21 }, { 29 }, { 36 }, { 59 }
- };
- #define DCF_P_P1 0
- #define DCF_P_P2 1
- #define DCF_P_P3 2
- #define DCF_Z_MET 0x2
- #define DCF_Z_MED 0x1
- static u_long
- ext_bf(
- unsigned char *buf,
- int idx,
- unsigned char *zero
- )
- {
- u_long sum = 0;
- int i, first;
- first = rawdcfcode[idx].offset;
-
- for (i = rawdcfcode[idx+1].offset - 1; i >= first; i--)
- {
- sum <<= 1;
- sum |= (buf[i] != zero[i]);
- }
- return sum;
- }
- static unsigned
- pcheck(
- unsigned char *buf,
- int idx,
- unsigned char *zero
- )
- {
- int i,last;
- unsigned psum = 1;
- last = partab[idx+1].offset;
- for (i = partab[idx].offset; i < last; i++)
- psum ^= (buf[i] != zero[i]);
- return psum;
- }
- static u_long
- convert_rawdcf(
- unsigned char *buffer,
- int size,
- struct dcfparam *dcfprm,
- clocktime_t *clock_time
- )
- {
- unsigned char *s = buffer;
- unsigned char *b = dcfprm->onebits;
- unsigned char *c = dcfprm->zerobits;
- int i;
- parseprintf(DD_RAWDCF,("parse: convert_rawdcf: \"%s\"\n", buffer));
- if (size < 57)
- {
- #ifndef PARSEKERNEL
- msyslog(LOG_ERR, "parse: convert_rawdcf: INCOMPLETE DATA - time code only has %d bits\n", size);
- #endif
- return CVT_NONE;
- }
-
- for (i = 0; i < size; i++)
- {
- if ((*s != *b) && (*s != *c))
- {
- /*
- * we only have two types of bytes (ones and zeros)
- */
- #ifndef PARSEKERNEL
- msyslog(LOG_ERR, "parse: convert_rawdcf: BAD DATA - no conversion");
- #endif
- return CVT_NONE;
- }
- if (*b) b++;
- if (*c) c++;
- s++;
- }
- /*
- * check Start and Parity bits
- */
- if ((ext_bf(buffer, DCF_S, dcfprm->zerobits) == 1) &&
- pcheck(buffer, DCF_P_P1, dcfprm->zerobits) &&
- pcheck(buffer, DCF_P_P2, dcfprm->zerobits) &&
- pcheck(buffer, DCF_P_P3, dcfprm->zerobits))
- {
- /*
- * buffer OK
- */
- parseprintf(DD_RAWDCF,("parse: convert_rawdcf: parity check passed\n"));
- clock_time->flags = PARSEB_S_ANTENNA|PARSEB_S_LEAP;
- clock_time->utctime= 0;
- clock_time->usecond= 0;
- clock_time->second = 0;
- clock_time->minute = ext_bf(buffer, DCF_M10, dcfprm->zerobits);
- clock_time->minute = TIMES10(clock_time->minute) + ext_bf(buffer, DCF_M1, dcfprm->zerobits);
- clock_time->hour = ext_bf(buffer, DCF_H10, dcfprm->zerobits);
- clock_time->hour = TIMES10(clock_time->hour) + ext_bf(buffer, DCF_H1, dcfprm->zerobits);
- clock_time->day = ext_bf(buffer, DCF_D10, dcfprm->zerobits);
- clock_time->day = TIMES10(clock_time->day) + ext_bf(buffer, DCF_D1, dcfprm->zerobits);
- clock_time->month = ext_bf(buffer, DCF_MO0, dcfprm->zerobits);
- clock_time->month = TIMES10(clock_time->month) + ext_bf(buffer, DCF_MO, dcfprm->zerobits);
- clock_time->year = ext_bf(buffer, DCF_Y10, dcfprm->zerobits);
- clock_time->year = TIMES10(clock_time->year) + ext_bf(buffer, DCF_Y1, dcfprm->zerobits);
- switch (ext_bf(buffer, DCF_Z, dcfprm->zerobits))
- {
- case DCF_Z_MET:
- clock_time->utcoffset = -1*60*60;
- break;
- case DCF_Z_MED:
- clock_time->flags |= PARSEB_DST;
- clock_time->utcoffset = -2*60*60;
- break;
- default:
- parseprintf(DD_RAWDCF,("parse: convert_rawdcf: BAD TIME ZONE\n"));
- return CVT_FAIL|CVT_BADFMT;
- }
- if (ext_bf(buffer, DCF_A1, dcfprm->zerobits))
- clock_time->flags |= PARSEB_ANNOUNCE;
- if (ext_bf(buffer, DCF_A2, dcfprm->zerobits))
- clock_time->flags |= PARSEB_LEAPADD; /* default: DCF77 data format deficiency */
- if (ext_bf(buffer, DCF_R, dcfprm->zerobits))
- clock_time->flags |= PARSEB_ALTERNATE;
- parseprintf(DD_RAWDCF,("parse: convert_rawdcf: TIME CODE OK: %d:%d, %d.%d.%d, flags 0x%lx\n",
- (int)clock_time->hour, (int)clock_time->minute, (int)clock_time->day, (int)clock_time->month,(int) clock_time->year,
- (u_long)clock_time->flags));
- return CVT_OK;
- }
- else
- {
- /*
- * bad format - not for us
- */
- #ifndef PARSEKERNEL
- msyslog(LOG_ERR, "parse: convert_rawdcf: parity check FAILED for \"%s\"\n", buffer);
- #endif
- return CVT_FAIL|CVT_BADFMT;
- }
- }
- /*
- * raw dcf input routine - needs to fix up 50 baud
- * characters for 1/0 decision
- */
- static u_long
- cvt_rawdcf(
- unsigned char *buffer,
- int size,
- struct format *param,
- clocktime_t *clock_time,
- void *local
- )
- {
- last_tcode_t *t = (last_tcode_t *)local;
- unsigned char *s = (unsigned char *)buffer;
- unsigned char *e = s + size;
- unsigned char *b = dcfparameter.onebits;
- unsigned char *c = dcfparameter.zerobits;
- u_long rtc = CVT_NONE;
- unsigned int i, lowmax, highmax, cutoff, span;
- #define BITS 9
- unsigned char histbuf[BITS];
- /*
- * the input buffer contains characters with runs of consecutive
- * bits set. These set bits are an indication of the DCF77 pulse
- * length. We assume that we receive the pulse at 50 Baud. Thus
- * a 100ms pulse would generate a 4 bit train (20ms per bit and
- * start bit)
- * a 200ms pulse would create all zeroes (and probably a frame error)
- */
- for (i = 0; i < BITS; i++)
- {
- histbuf[i] = 0;
- }
- cutoff = 0;
- lowmax = 0;
- while (s < e)
- {
- unsigned int ch = *s ^ 0xFF;
- /*
- * these lines are left as an excercise to the reader 8-)
- */
- if (!((ch+1) & ch) || !*s)
- {
- for (i = 0; ch; i++)
- {
- ch >>= 1;
- }
- *s = i;
- histbuf[i]++;
- cutoff += i;
- lowmax++;
- }
- else
- {
- parseprintf(DD_RAWDCF,("parse: cvt_rawdcf: character check for 0x%x@%d FAILED\n", *s, (int)(s - (unsigned char *)buffer)));
- *s = (unsigned char)~0;
- rtc = CVT_FAIL|CVT_BADFMT;
- }
- s++;
- }
- if (lowmax)
- {
- cutoff /= lowmax;
- }
- else
- {
- cutoff = 4; /* doesn't really matter - it'll fail anyway, but gives error output */
- }
- parseprintf(DD_RAWDCF,("parse: cvt_rawdcf: average bit count: %d\n", cutoff));
- lowmax = 0;
- highmax = 0;
- parseprintf(DD_RAWDCF,("parse: cvt_rawdcf: histogram:"));
- for (i = 0; i <= cutoff; i++)
- {
- lowmax+=histbuf[i] * i;
- highmax += histbuf[i];
- parseprintf(DD_RAWDCF,(" %d", histbuf[i]));
- }
- parseprintf(DD_RAWDCF, (" <M>"));
- lowmax += highmax / 2;
- if (highmax)
- {
- lowmax /= highmax;
- }
- else
- {
- lowmax = 0;
- }
- highmax = 0;
- cutoff = 0;
- for (; i < BITS; i++)
- {
- highmax+=histbuf[i] * i;
- cutoff +=histbuf[i];
- parseprintf(DD_RAWDCF,(" %d", histbuf[i]));
- }
- parseprintf(DD_RAWDCF,("\n"));
- if (cutoff)
- {
- highmax /= cutoff;
- }
- else
- {
- highmax = BITS-1;
- }
- span = cutoff = lowmax;
- for (i = lowmax; i <= highmax; i++)
- {
- if (histbuf[cutoff] > histbuf[i])
- {
- cutoff = i;
- span = i;
- }
- else
- if (histbuf[cutoff] == histbuf[i])
- {
- span = i;
- }
- }
- cutoff = (cutoff + span) / 2;
- parseprintf(DD_RAWDCF,("parse: cvt_rawdcf: lower maximum %d, higher maximum %d, cutoff %d\n", lowmax, highmax, cutoff));
- s = (unsigned char *)buffer;
- while (s < e)
- {
- if (*s == (unsigned char)~0)
- {
- *s = '?';
- }
- else
- {
- *s = (*s >= cutoff) ? *b : *c;
- }
- s++;
- if (*b) b++;
- if (*c) c++;
- }
- if (rtc == CVT_NONE)
- {
- rtc = convert_rawdcf(buffer, size, &dcfparameter, clock_time);
- if (rtc == CVT_OK)
- {
- time_t newtime;
- newtime = parse_to_unixtime(clock_time, &rtc);
- if ((rtc == CVT_OK) && t)
- {
- if ((newtime - t->tcode) == 60) /* guard against multi bit errors */
- {
- clock_time->utctime = newtime;
- }
- else
- {
- rtc = CVT_FAIL|CVT_BADTIME;
- }
- t->tcode = newtime;
- }
- }
- }
-
- return rtc;
- }
- /*
- * pps_rawdcf
- *
- * currently a very stupid version - should be extended to decode
- * also ones and zeros (which is easy)
- */
- /*ARGSUSED*/
- static u_long
- pps_rawdcf(
- parse_t *parseio,
- int status,
- timestamp_t *ptime
- )
- {
- if (!status) /* negative edge for simpler wiring (Rx->DCD) */
- {
- parseio->parse_dtime.parse_ptime = *ptime;
- parseio->parse_dtime.parse_state |= PARSEB_PPS|PARSEB_S_PPS;
- }
- return CVT_NONE;
- }
- static u_long
- snt_rawdcf(
- parse_t *parseio,
- timestamp_t *ptime
- )
- {
- if ((parseio->parse_dtime.parse_status & CVT_MASK) == CVT_OK)
- {
- parseio->parse_dtime.parse_stime = *ptime;
- #ifdef PARSEKERNEL
- parseio->parse_dtime.parse_time.tv.tv_sec++;
- #else
- parseio->parse_dtime.parse_time.fp.l_ui++;
- #endif
-
- parseprintf(DD_RAWDCF,("parse: snt_rawdcf: time stamp synthesized offset %d seconds\n", parseio->parse_index - 1));
-
- return updatetimeinfo(parseio, parseio->parse_lstate);
- }
- return CVT_NONE;
- }
- /*
- * inp_rawdcf
- *
- * grab DCF77 data from input stream
- */
- static u_long
- inp_rawdcf(
- parse_t *parseio,
- unsigned int ch,
- timestamp_t *tstamp
- )
- {
- static struct timeval timeout = { 1, 500000 }; /* 1.5 secongs denote second #60 */
-
- parseprintf(DD_PARSE, ("inp_rawdcf(0x%lx, 0x%x, ...)\n", (long)parseio, ch));
-
- parseio->parse_dtime.parse_stime = *tstamp; /* collect timestamp */
- if (parse_timedout(parseio, tstamp, &timeout))
- {
- parseprintf(DD_PARSE, ("inp_rawdcf: time out seen\n"));
- (void) parse_end(parseio);
- (void) parse_addchar(parseio, ch);
- return PARSE_INP_TIME;
- }
- else
- {
- unsigned int rtc;
-
- rtc = parse_addchar(parseio, ch);
- if (rtc == PARSE_INP_SKIP)
- {
- if (snt_rawdcf(parseio, tstamp) == CVT_OK)
- return PARSE_INP_SYNTH;
- }
- return rtc;
- }
- }
- #else /* not (REFCLOCK && CLOCK_PARSE && CLOCK_RAWDCF) */
- int clk_rawdcf_bs;
- #endif /* not (REFCLOCK && CLOCK_PARSE && CLOCK_RAWDCF) */
- /*
- * History:
- *
- * clk_rawdcf.c,v
- * Revision 4.18 2006/06/22 18:40:01 kardel
- * clean up signedness (gcc 4)
- *
- * Revision 4.17 2006/01/22 16:01:55 kardel
- * update version information
- *
- * Revision 4.16 2006/01/22 15:51:22 kardel
- * generate reasonable timecode output on invalid input
- *
- * Revision 4.15 2005/08/06 19:17:06 kardel
- * clean log output
- *
- * Revision 4.14 2005/08/06 17:39:40 kardel
- * cleanup size handling wrt/ to buffer boundaries
- *
- * Revision 4.13 2005/04/16 17:32:10 kardel
- * update copyright
- *
- * Revision 4.12 2004/11/14 15:29:41 kardel
- * support PPSAPI, upgrade Copyright to Berkeley style
- *
- * Revision 4.9 1999/12/06 13:42:23 kardel
- * transfer correctly converted time codes always into tcode
- *
- * Revision 4.8 1999/11/28 09:13:50 kardel
- * RECON_4_0_98F
- *
- * Revision 4.7 1999/04/01 20:07:20 kardel
- * added checking for minutie increment of timestamps in clk_rawdcf.c
- *
- * Revision 4.6 1998/06/14 21:09:37 kardel
- * Sun acc cleanup
- *
- * Revision 4.5 1998/06/13 12:04:16 kardel
- * fix SYSV clock name clash
- *
- * Revision 4.4 1998/06/12 15:22:28 kardel
- * fix prototypes
- *
- * Revision 4.3 1998/06/06 18:33:36 kardel
- * simplified condidional compile expression
- *
- * Revision 4.2 1998/05/24 11:04:18 kardel
- * triggering PPS on negative edge for simpler wiring (Rx->DCD)
- *
- * Revision 4.1 1998/05/24 09:39:53 kardel
- * implementation of the new IO handling model
- *
- * Revision 4.0 1998/04/10 19:45:30 kardel
- * Start 4.0 release version numbering
- *
- * from V3 3.24 log info deleted 1998/04/11 kardel
- *
- */