NetBSD/usr.sbin/xntp/xntpd/clk_rawdcf.c

610 lines
15 KiB
C

/*
* /src/NTP/REPOSITORY/v4/libparse/clk_rawdcf.c,v 3.23 1997/01/19 12:44:39 kardel Exp
*
* clk_rawdcf.c,v 3.23 1997/01/19 12:44:39 kardel Exp
*
* Raw DCF77 pulse clock support
*
* Copyright (C) 1992,1993,1994,1995,1996 by Frank Kardel
* Friedrich-Alexander Universität Erlangen-Nürnberg, Germany
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
*
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#if defined(REFCLOCK) && (defined(PARSE) || defined(PARSEPPS)) && defined(CLOCK_RAWDCF)
#include <sys/types.h>
#include <sys/time.h>
#include <sys/errno.h>
#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 cvt_rawdcf();
static u_long pps_rawdcf();
static u_long snt_rawdcf();
clockformat_t clock_rawdcf =
{
(unsigned long (*)())0, /* no input handling */
cvt_rawdcf, /* raw dcf input conversion */
(void (*)())0, /* no character bound synchronisation */
pps_rawdcf, /* examining PPS information */
snt_rawdcf, /* synthesize time code from input */
(void *)0, /* buffer bit representation */
"RAW DCF77 Timecode", /* direct decoding / time synthesis */
61, /* bit buffer */
SYNC_ONE|SYNC_ZERO|SYNC_TIMEOUT|SYNC_SYNTHESIZE|CVT_FIXEDONLY,
/* catch all transitions, buffer restart on timeout, fixed configuration only */
0, /* no private data (currently in input buffer) */
{ 1, 500000}, /* restart after 1.5 seconds */
'\0',
'\0',
'\0'
};
static struct dcfparam
{
unsigned char onebits[60];
unsigned char zerobits[60];
} dcfparam =
{
"###############RADMLS1248124P124812P1248121241248112481248P", /* 'ONE' representation */
"--------------------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(buf, idx, zero)
register char *buf;
register int idx;
register char *zero;
{
register u_long sum = 0;
register 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(buf, idx, zero)
register char *buf;
register int idx;
register char *zero;
{
register int i,last;
register 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(buffer, size, dcfparam, clock)
register unsigned char *buffer;
register int size;
register struct dcfparam *dcfparam;
register clocktime_t *clock;
{
register unsigned char *s = buffer;
register unsigned char *b = dcfparam->onebits;
register unsigned char *c = dcfparam->zerobits;
register int i;
parseprintf(DD_RAWDCF,("parse: convert_rawdcf: \"%s\"\n", buffer));
if (size < 57)
{
#ifdef PARSEKERNEL
printf("parse: convert_rawdcf: INCOMPLETE DATA - time code only has %d bits\n", size);
#else
msyslog(LOG_ERR, "parse: convert_rawdcf: INCOMPLETE DATA - time code only has %d bits\n", size);
#endif
return CVT_NONE;
}
for (i = 0; i < 58; i++)
{
if ((*s != *b) && (*s != *c))
{
/*
* we only have two types of bytes (ones and zeros)
*/
#ifdef PARSEKERNEL
printf("parse: convert_rawdcf: BAD DATA - no conversion for \"%s\"\n", buffer);
#else
msyslog(LOG_ERR, "parse: convert_rawdcf: BAD DATA - no conversion for \"%s\"\n", buffer);
#endif
return CVT_NONE;
}
b++;
c++;
s++;
}
/*
* check Start and Parity bits
*/
if ((ext_bf(buffer, DCF_S, dcfparam->zerobits) == 1) &&
pcheck(buffer, DCF_P_P1, dcfparam->zerobits) &&
pcheck(buffer, DCF_P_P2, dcfparam->zerobits) &&
pcheck(buffer, DCF_P_P3, dcfparam->zerobits))
{
/*
* buffer OK
*/
parseprintf(DD_RAWDCF,("parse: convert_rawdcf: parity check passed\n"));
clock->flags = PARSEB_S_ANTENNA|PARSEB_S_LEAP;
clock->utctime= 0;
clock->usecond= 0;
clock->second = 0;
clock->minute = ext_bf(buffer, DCF_M10, dcfparam->zerobits);
clock->minute = TIMES10(clock->minute) + ext_bf(buffer, DCF_M1, dcfparam->zerobits);
clock->hour = ext_bf(buffer, DCF_H10, dcfparam->zerobits);
clock->hour = TIMES10(clock->hour) + ext_bf(buffer, DCF_H1, dcfparam->zerobits);
clock->day = ext_bf(buffer, DCF_D10, dcfparam->zerobits);
clock->day = TIMES10(clock->day) + ext_bf(buffer, DCF_D1, dcfparam->zerobits);
clock->month = ext_bf(buffer, DCF_MO0, dcfparam->zerobits);
clock->month = TIMES10(clock->month) + ext_bf(buffer, DCF_MO, dcfparam->zerobits);
clock->year = ext_bf(buffer, DCF_Y10, dcfparam->zerobits);
clock->year = TIMES10(clock->year) + ext_bf(buffer, DCF_Y1, dcfparam->zerobits);
switch (ext_bf(buffer, DCF_Z, dcfparam->zerobits))
{
case DCF_Z_MET:
clock->utcoffset = -1*60*60;
break;
case DCF_Z_MED:
clock->flags |= PARSEB_DST;
clock->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, dcfparam->zerobits))
clock->flags |= PARSEB_ANNOUNCE;
if (ext_bf(buffer, DCF_A2, dcfparam->zerobits))
clock->flags |= PARSEB_LEAPADD; /* default: DCF77 data format deficiency */
if (ext_bf(buffer, DCF_R, dcfparam->zerobits))
clock->flags |= PARSEB_ALTERNATE;
parseprintf(DD_RAWDCF,("parse: convert_rawdcf: TIME CODE OK: %d:%d, %d.%d.%d, flags 0x%lx\n",
(int)clock->hour, (int)clock->minute, (int)clock->day, (int)clock->month,(int) clock->year,
(u_long)clock->flags));
return CVT_OK;
}
else
{
/*
* bad format - not for us
*/
#ifdef PARSEKERNEL
printf("parse: convert_rawdcf: parity check FAILED for \"%s\"\n", buffer);
#else
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(buffer, size, param, clock)
register unsigned char *buffer;
register int size;
register void *param;
register clocktime_t *clock;
{
register unsigned char *s = buffer;
register unsigned char *e = buffer + size;
register unsigned char *b = dcfparam.onebits;
register unsigned char *c = dcfparam.zerobits;
register unsigned rtc = CVT_NONE;
register 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)
{
register 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, s - buffer));
*s = ~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 = buffer;
while ((s < e) && *c && *b)
{
if (*s == (unsigned char)~0)
{
*s = '?';
}
else
{
*s = (*s >= cutoff) ? *b : *c;
}
s++;
b++;
c++;
}
return (rtc == CVT_NONE) ? convert_rawdcf(buffer, size, &dcfparam, clock) : 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(parseio, status, ptime)
register parse_t *parseio;
register int status;
register timestamp_t *ptime;
{
if (status)
{
parseio->parse_dtime.parse_ptime = *ptime;
parseio->parse_dtime.parse_state |= PARSEB_PPS|PARSEB_S_PPS;
}
return CVT_NONE;
}
/*ARGSUSED*/
static u_long snt_rawdcf(parseio, ptime)
register parse_t *parseio;
register timestamp_t *ptime;
{
clocktime_t clock;
u_long cvtrtc;
time_t t;
/*
* start at last sample and add second index - gross, may have to be much more careful
*/
if (convert_rawdcf(parseio->parse_ldata, parseio->parse_ldsize - 1, &dcfparam, &clock) == CVT_OK)
{
if ((t = parse_to_unixtime(&clock, &cvtrtc)) == -1)
{
parseprintf(DD_RAWDCF,("parse: snt_rawdcf: time conversion FAILED\n"));
return CVT_FAIL|cvtrtc;
}
}
else
{
parseprintf(DD_RAWDCF,("parse: snt_rawdcf: data conversion FAILED\n"));
return CVT_NONE;
}
parseio->parse_dtime.parse_stime = *ptime;
t += parseio->parse_index - 1;
/*
* time stamp
*/
#ifdef PARSEKERNEL
parseio->parse_dtime.parse_time.tv.tv_sec = t;
parseio->parse_dtime.parse_time.tv.tv_usec = clock.usecond;
#else
parseio->parse_dtime.parse_time.fp.l_ui = t + JAN_1970;
TVUTOTSF(clock.usecond, parseio->parse_dtime.parse_time.fp.l_uf);
#endif
parseprintf(DD_RAWDCF,("parse: snt_rawdcf: time stamp synthesized offset %d seconds\n", parseio->parse_index - 1));
return updatetimeinfo(parseio, t, clock.usecond, clock.flags);
}
#else /* not (REFCLOCK && (PARSE || PARSEPPS) && CLOCK_RAWDCF) */
int clk_rawdcf_bs;
#endif /* not (REFCLOCK && (PARSE || PARSEPPS) && CLOCK_RAWDCF) */
/*
* History:
*
* clk_rawdcf.c,v
* Revision 3.23 1997/01/19 12:44:39 kardel
* 3-5.88.1 reconcilation
*
* Revision 3.22 1996/12/01 16:04:15 kardel
* freeze for 5.86.12.2 PARSE-Patch
*
* Revision 3.21 1996/11/24 23:16:31 kardel
* checkpoint - partial autoconfigure update for parse modules
*
* Revision 3.20 1996/11/24 20:09:45 kardel
* RELEASE_5_86_12_2 reconcilation
*
* Revision 3.19 1996/10/05 13:30:20 kardel
* general update
*
* Revision 3.18 1994/10/03 21:59:22 kardel
* 3.4e cleanup/integration
*
* Revision 3.17 1994/10/03 10:04:07 kardel
* 3.4e reconcilation
*
* Revision 3.16 1994/05/31 20:02:40 kardel
* sync on ONE transition
*
* Revision 3.15 1994/05/30 10:20:01 kardel
* LONG cleanup
*
* Revision 3.14 1994/05/12 12:49:09 kardel
* printf fmt/arg cleanup
*
* Revision 3.13 1994/03/10 19:00:43 kardel
* clear utctime field to avoid confusion on synthesize time stamps
*
* Revision 3.12 1994/02/20 13:04:39 kardel
* parse add/delete second support
*
* Revision 3.11 1994/02/02 17:45:23 kardel
* rcs ids fixed
*
* Revision 3.9 1994/01/25 19:05:12 kardel
* 94/01/23 reconcilation
*
* Revision 3.8 1994/01/22 11:24:11 kardel
* fixed PPS handling
*
* Revision 3.7 1993/10/30 09:44:41 kardel
* conditional compilation flag cleanup
*
* Revision 3.6 1993/10/03 19:10:45 kardel
* restructured I/O handling
*
* Revision 3.5 1993/09/27 21:08:07 kardel
* utcoffset now in seconds
*
* Revision 3.4 1993/09/26 23:40:25 kardel
* new parse driver logic
*
* Revision 3.3 1993/09/01 21:44:54 kardel
* conditional cleanup
*
* Revision 3.2 1993/07/09 11:37:18 kardel
* Initial restructured version + GPS support
*
* Revision 3.1 1993/07/06 10:00:19 kardel
* DCF77 driver goes generic...
*
*/