320 lines
8.1 KiB
C
320 lines
8.1 KiB
C
/*
|
|
* refclock_ulink - clock driver for Ultralink Model 320 WWVB receivers
|
|
* By Dave Strout <dstrout@linuxfoundary.com>
|
|
*
|
|
* Latest version is always on www.linuxfoundary.com
|
|
*
|
|
* Based on the Spectracom driver
|
|
*/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include <config.h>
|
|
#endif
|
|
|
|
#if defined(REFCLOCK) && defined(CLOCK_ULINK)
|
|
|
|
#include <stdio.h>
|
|
#include <ctype.h>
|
|
#include <sys/time.h>
|
|
#include <time.h>
|
|
|
|
#include "ntpd.h"
|
|
#include "ntp_io.h"
|
|
#include "ntp_refclock.h"
|
|
#include "ntp_calendar.h"
|
|
#include "ntp_stdlib.h"
|
|
|
|
/*
|
|
* This driver supports the Ultralink Model 320 WWVB receiver. The Model 320 is
|
|
* an RS-232 powered unit which consists of two parts: a DB-25 shell that contains
|
|
* a microprocessor, and an approx 2"x4" plastic box that contains the antenna.
|
|
* The two are connected by a 6-wire RJ-25 cable of length up to 1000'. The
|
|
* microprocessor steals power from the RS-232 port, which means that the port must
|
|
* be kept open all of the time. The unit also has an internal clock for loss of signal
|
|
* periods. Claimed accuracy is 0.1 sec.
|
|
*
|
|
* The timecode format is:
|
|
*
|
|
* <cr><lf>SQRYYYYDDD+HH:MM:SS.mmLT<cr>
|
|
*
|
|
* where:
|
|
*
|
|
* S = 'S' -- sync'd in last hour, '0'-'9' - hours x 10 since last update, else '?'
|
|
* Q = Number of correlating time-frames, from 0 to 5
|
|
* R = 'R' -- reception in progress, 'N' -- Noisy reception, ' ' -- standby mode
|
|
* YYYY = year from 1990 to 2089
|
|
* DDD = current day from 1 to 366
|
|
* + = '+' if current year is a leap year, else ' '
|
|
* HH = UTC hour 0 to 23
|
|
* MM = Minutes of current hour from 0 to 59
|
|
* SS = Seconds of current minute from 0 to 59
|
|
* mm = 10's milliseconds of the current second from 00 to 99
|
|
* L = Leap second pending at end of month -- 'I' = inset, 'D'=delete
|
|
* T = DST <-> STD transition indicators
|
|
*
|
|
* Note that this driver does not do anything with the L or T flags.
|
|
*
|
|
* The M320 also has a 'U' command which returns UT1 correction information. It
|
|
* is not used in this driver.
|
|
*
|
|
*/
|
|
|
|
/*
|
|
* Interface definitions
|
|
*/
|
|
#define DEVICE "/dev/ulink%d" /* device name and unit */
|
|
#define SPEED232 B9600 /* uart speed (9600 baud) */
|
|
#define PRECISION (-13) /* precision assumed (about 100 us) */
|
|
#define REFID "M320" /* reference ID */
|
|
#define DESCRIPTION "Ultralink WWVB Receiver" /* WRU */
|
|
|
|
#define LENWWVB0 28 /* format 0 timecode length */
|
|
#define LENWWVB2 24 /* format 2 timecode length */
|
|
#define LENWWVB3 29 /* format 3 timecode length */
|
|
|
|
#define MONLIN 15 /* number of monitoring lines */
|
|
|
|
/*
|
|
* ULINK unit control structure
|
|
*/
|
|
struct ulinkunit {
|
|
u_char tcswitch; /* timecode switch */
|
|
l_fp laststamp; /* last receive timestamp */
|
|
u_char lasthour; /* last hour (for monitor) */
|
|
u_char linect; /* count ignored lines (for monitor */
|
|
};
|
|
|
|
/*
|
|
* Function prototypes
|
|
*/
|
|
static int ulink_start P((int, struct peer *));
|
|
static void ulink_shutdown P((int, struct peer *));
|
|
static void ulink_receive P((struct recvbuf *));
|
|
static void ulink_poll P((int, struct peer *));
|
|
static int fd; /* We need to keep the serial port open to power the ULM320 */
|
|
|
|
/*
|
|
* Transfer vector
|
|
*/
|
|
struct refclock refclock_ulink = {
|
|
ulink_start, /* start up driver */
|
|
ulink_shutdown, /* shut down driver */
|
|
ulink_poll, /* transmit poll message */
|
|
noentry, /* not used (old wwvb_control) */
|
|
noentry, /* initialize driver (not used) */
|
|
noentry, /* not used (old wwvb_buginfo) */
|
|
NOFLAGS /* not used */
|
|
};
|
|
|
|
|
|
/*
|
|
* ulink_start - open the devices and initialize data for processing
|
|
*/
|
|
static int
|
|
ulink_start(
|
|
int unit,
|
|
struct peer *peer
|
|
)
|
|
{
|
|
register struct ulinkunit *up;
|
|
struct refclockproc *pp;
|
|
char device[20];
|
|
fprintf(stderr, "Starting Ulink driver\n");
|
|
/*
|
|
* Open serial port. Use CLK line discipline, if available.
|
|
*/
|
|
(void)sprintf(device, DEVICE, unit);
|
|
if (!(fd = refclock_open(device, SPEED232, LDISC_CLK)))
|
|
return (0);
|
|
|
|
/*
|
|
* Allocate and initialize unit structure
|
|
*/
|
|
if (!(up = (struct ulinkunit *)
|
|
emalloc(sizeof(struct ulinkunit)))) {
|
|
(void) close(fd);
|
|
return (0);
|
|
}
|
|
memset((char *)up, 0, sizeof(struct ulinkunit));
|
|
pp = peer->procptr;
|
|
pp->unitptr = (caddr_t)up;
|
|
pp->io.clock_recv = ulink_receive;
|
|
pp->io.srcclock = (caddr_t)peer;
|
|
pp->io.datalen = 0;
|
|
pp->io.fd = fd;
|
|
if (!io_addclock(&pp->io)) {
|
|
(void) close(fd);
|
|
free(up);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Initialize miscellaneous variables
|
|
*/
|
|
peer->precision = PRECISION;
|
|
peer->flags |= FLAG_BURST;
|
|
peer->burst = NSTAGE;
|
|
pp->clockdesc = DESCRIPTION;
|
|
memcpy((char *)&pp->refid, REFID, 4);
|
|
return (1);
|
|
}
|
|
|
|
|
|
/*
|
|
* ulink_shutdown - shut down the clock
|
|
*/
|
|
static void
|
|
ulink_shutdown(
|
|
int unit,
|
|
struct peer *peer
|
|
)
|
|
{
|
|
register struct ulinkunit *up;
|
|
struct refclockproc *pp;
|
|
|
|
pp = peer->procptr;
|
|
up = (struct ulinkunit *)pp->unitptr;
|
|
io_closeclock(&pp->io);
|
|
free(up);
|
|
close(fd);
|
|
}
|
|
|
|
|
|
/*
|
|
* ulink_receive - receive data from the serial interface
|
|
*/
|
|
static void
|
|
ulink_receive(
|
|
struct recvbuf *rbufp
|
|
)
|
|
{
|
|
struct ulinkunit *up;
|
|
struct refclockproc *pp;
|
|
struct peer *peer;
|
|
|
|
l_fp trtmp; /* arrival timestamp */
|
|
char syncchar; /* synchronization indicator */
|
|
char qualchar; /* quality indicator */
|
|
char modechar; /* Modes: 'R'=rx, 'N'=noise, ' '=standby */
|
|
char leapchar; /* leap indicator */
|
|
int temp; /* int temp */
|
|
|
|
/*
|
|
* Initialize pointers and read the timecode and timestamp
|
|
*/
|
|
peer = (struct peer *)rbufp->recv_srcclock;
|
|
pp = peer->procptr;
|
|
up = (struct ulinkunit *)pp->unitptr;
|
|
temp = refclock_gtlin(rbufp, pp->a_lastcode, BMAX, &trtmp);
|
|
|
|
/*
|
|
* Note we get a buffer and timestamp for both a <cr> and <lf>,
|
|
* but only the <cr> timestamp is retained. Note: in format 0 on
|
|
* a Netclock/2 or upgraded 8170 the start bit is delayed 100
|
|
* +-50 us relative to the pps; however, on an unmodified 8170
|
|
* the start bit can be delayed up to 10 ms. In format 2 the
|
|
* reading precision is only to the millisecond. Thus, unless
|
|
* you have a pps gadget and don't have to have the year, format
|
|
* 0 provides the lowest jitter.
|
|
*/
|
|
if (temp == 0) {
|
|
if (up->tcswitch == 0) {
|
|
up->tcswitch = 1;
|
|
up->laststamp = trtmp;
|
|
} else
|
|
up->tcswitch = 0;
|
|
return;
|
|
}
|
|
pp->lencode = temp;
|
|
pp->lastrec = up->laststamp;
|
|
up->laststamp = trtmp;
|
|
up->tcswitch = 1;
|
|
#ifdef DEBUG
|
|
if (debug)
|
|
printf("ulink: timecode %d %s\n", pp->lencode,
|
|
pp->a_lastcode);
|
|
#endif
|
|
|
|
/*
|
|
* We get down to business, check the timecode format and decode
|
|
* its contents. This code uses the timecode length to determine
|
|
* whether format 0 or format 2. If the timecode has invalid
|
|
* length or is not in proper format, we declare bad format and
|
|
* exit.
|
|
*/
|
|
syncchar = qualchar = leapchar = ' ';
|
|
pp->msec = 0;
|
|
|
|
/*
|
|
* Timecode format SQRYYYYDDD+HH:MM:SS.mmLT
|
|
*/
|
|
sscanf(pp->a_lastcode, "%c%c%c%4d%3d%c%2d:%2d:%2d.%2d",
|
|
&syncchar, &qualchar, &modechar, &pp->year, &pp->day,
|
|
&leapchar,&pp->hour, &pp->minute, &pp->second,&pp->msec);
|
|
|
|
pp->msec *= 10; /* M320 returns 10's of msecs */
|
|
qualchar = ' ';
|
|
|
|
/*
|
|
* Decode synchronization, quality and leap characters. If
|
|
* unsynchronized, set the leap bits accordingly and exit.
|
|
* Otherwise, set the leap bits according to the leap character.
|
|
* Once synchronized, the dispersion depends only on the
|
|
* quality character.
|
|
*/
|
|
pp->disp = .001;
|
|
pp->leap = LEAP_NOWARNING;
|
|
|
|
/*
|
|
* Process the new sample in the median filter and determine the
|
|
* timecode timestamp.
|
|
*/
|
|
if (!refclock_process(pp))
|
|
refclock_report(peer, CEVNT_BADTIME);
|
|
}
|
|
|
|
|
|
/*
|
|
* ulink_poll - called by the transmit procedure
|
|
*/
|
|
static void
|
|
ulink_poll(
|
|
int unit,
|
|
struct peer *peer
|
|
)
|
|
{
|
|
register struct ulinkunit *up;
|
|
struct refclockproc *pp;
|
|
char pollchar;
|
|
|
|
pp = peer->procptr;
|
|
up = (struct ulinkunit *)pp->unitptr;
|
|
pollchar = 'T';
|
|
if (write(pp->io.fd, &pollchar, 1) != 1)
|
|
refclock_report(peer, CEVNT_FAULT);
|
|
else
|
|
pp->polls++;
|
|
if (peer->burst > 0)
|
|
return;
|
|
if (pp->coderecv == pp->codeproc) {
|
|
refclock_report(peer, CEVNT_TIMEOUT);
|
|
return;
|
|
}
|
|
record_clock_stats(&peer->srcadr, pp->a_lastcode);
|
|
refclock_receive(peer);
|
|
peer->burst = NSTAGE;
|
|
|
|
/*
|
|
* If the monitor flag is set (flag4), we dump the internal
|
|
* quality table at the first timecode beginning the day.
|
|
*/
|
|
if (pp->sloppyclockflag & CLK_FLAG4 && pp->hour <
|
|
(int)up->lasthour)
|
|
up->linect = MONLIN;
|
|
up->lasthour = pp->hour;
|
|
}
|
|
|
|
#else
|
|
int refclock_ulink_bs;
|
|
#endif /* REFCLOCK */
|