/*
* refclock_true - clock driver for the Kinemetrics/TrueTime receivers
* Receiver Version 3.0C - tested plain, with CLKLDISC
* Development work being done:
* - Support TL-3 WWV TOD receiver
*/
/* This should be an atom clock but those are very hard to build.
*
* The PCL720 from P C Labs has an Intel 8253 lookalike, as well as a bunch
* of TTL input and output pins, all brought out to the back panel. If you
* wire a PPS signal (such as the TTL PPS coming out of a GOES or other
* Kinemetrics/Truetime clock) to the 8253's GATE0, and then also wire the
* 8253's OUT0 to the PCL720's INPUT3.BIT0, then we can read CTR0 to get the
* number of uSecs since the last PPS upward swing, mediated by reading OUT0
* to find out if the counter has wrapped around (this happens if more than
* 65535us (65ms) elapses between the PPS event and our being called.)
*/
#ifdef CLOCK_PPS720
# undef min /* XXX */
# undef max /* XXX */
# include <machine/inline.h>
# include <sys/pcl720.h>
# include <sys/i8253.h>
# define PCL720_IOB 0x2a0 /* XXX */
# define PCL720_CTR 0 /* XXX */
#endif
/*
* Support for Kinemetrics Truetime Receivers
* GOES: (468-DC, usable with GPS->GOES converting antenna)
* GPS/TM-TMD:
* XL-DC: (a 151-602-210, reported by the driver as a GPS/TM-TMD)
* GPS-800 TCU: (an 805-957 with the RS232 Talker/Listener module)
* TL-3: 3 channel WWV/H receiver w/ IRIG and RS-232 outputs
* OM-DC: getting stale ("OMEGA")
*
* Most of this code is originally from refclock_wwvb.c with thanks.
* It has been so mangled that wwvb is not a recognizable ancestor.
*
* Timcode format: ADDD:HH:MM:SSQCL
* A - control A (this is stripped before we see it)
* Q - Quality indication (see below)
* C - Carriage return
* L - Line feed
*
* Quality codes indicate possible error of
* 468-DC GOES Receiver:
* GPS-TM/TMD Receiver: (default quality codes for XL-DC)
* ? +/- 1 milliseconds # +/- 100 microseconds
* * +/- 10 microseconds . +/- 1 microsecond
* space less than 1 microsecond
* TL-3 Receiver: (default quality codes for TL-3)
* ? unknown quality (receiver is unlocked)
* space +/- 5 milliseconds
* OM-DC OMEGA Receiver: (default quality codes for OMEGA)
* WARNING OMEGA navigation system is no longer existent
* > >+- 5 seconds
* ? >+/- 500 milliseconds # >+/- 50 milliseconds
* * >+/- 5 milliseconds . >+/- 1 millisecond
* A-H less than 1 millisecond. Character indicates which station
* is being received as follows:
* A = Norway, B = Liberia, C = Hawaii, D = North Dakota,
* E = La Reunion, F = Argentina, G = Australia, H = Japan.
*
* The carriage return start bit begins on 0 seconds and extends to 1 bit time.
*
* Notes on 468-DC and OMEGA receiver:
*
* Send the clock a 'R' or 'C' and once per second a timestamp will
* appear. Send a 'P' to get the satellite position once (GOES only.)
*
* Notes on the 468-DC receiver:
*
* Since the old east/west satellite locations are only historical, you can't
* set your clock propagation delay settings correctly and still use
* automatic mode. The manual says to use a compromise when setting the
* switches. This results in significant errors. The solution; use fudge
* time1 and time2 to incorporate corrections. If your clock is set for
* 50 and it should be 58 for using the west and 46 for using the east,
* use the line
*
* fudge 127.127.5.0 time1 +0.008 time2 -0.004
*
* This corrects the 4 milliseconds advance and 8 milliseconds retard
* needed. The software will ask the clock which satellite it sees.
*
* Notes on the TrueTime TimeLink TL-3 WWV TOD receiver:
*
* This clock may be polled, or send one timecode per second.
* That mode may be toggled via the front panel ("C" mode), or controlled
* from the RS-232 port. Send the receiver "ST1" to turn it on, and
* "ST0" to turn it off. Send "QV" to get the firmware revision (useful
* for identifying this model.)
*
* Note that it can take several polling cycles, especially if the receiver
* was in the continuous timecode mode. (It can be slow to leave that mode.)
*
* ntp.conf parameters:
* time1 - offset applied to samples when reading WEST satellite (default = 0)
* time2 - offset applied to samples when reading EAST satellite (default = 0)
* stratum - stratum to assign to this clock (default = 0)
* refid - refid assigned to this clock (default = "TRUE", see below)
* flag1 - will silence the clock side of ntpd, just reading the clock
* without trying to write to it. (default = 0)
* flag2 - generate a debug file /tmp/true%d.
* flag3 - enable ppsclock streams module
* flag4 - use the PCL-720 (BSD/OS only)
*/
/*
* Tags which station (satellite) we see
*/
#define GOES_WEST 0 /* Default to WEST satellite and apply time1 */
#define GOES_EAST 1 /* until you discover otherwise */
/*
* unit control structure
*/
struct true_unit {
unsigned int pollcnt; /* poll message counter */
unsigned int station; /* which station we are on */
unsigned int polled; /* Hand in a time sample? */
enum true_state state; /* state machine */
enum true_type type; /* what kind of clock is it? */
int unit; /* save an extra copy of this */
FILE *debug; /* debug logging file */
#ifdef CLOCK_PPS720
int pcl720init; /* init flag for PCL 720 */
#endif
};
/*
* true_start - open the devices and initialize data for processing
*/
static int
true_start(
int unit,
struct peer *peer
)
{
register struct true_unit *up;
struct refclockproc *pp;
char device[40];
int fd;
/*
* Open serial port
*/
snprintf(device, sizeof(device), DEVICE, unit);
fd = refclock_open(&peer->srcadr, device, SPEED232, LDISC_CLK);
if (fd <= 0)
return 0;
/*
* Allocate and initialize unit structure
*/
up = emalloc_zero(sizeof(*up));
pp = peer->procptr;
pp->io.clock_recv = true_receive;
pp->io.srcclock = peer;
pp->io.datalen = 0;
pp->io.fd = fd;
if (!io_addclock(&pp->io)) {
close(fd);
pp->io.fd = -1;
free(up);
return (0);
}
pp->unitptr = up;
/*
* Send a CTRL-C character at the start,
* just in case the clock is already
* sending timecodes
*/
true_send(peer, "\03\r");
true_doevent(peer, e_Init);
return (1);
}
/*
* true_shutdown - shut down the clock
*/
static void
true_shutdown(
int unit,
struct peer *peer
)
{
register struct true_unit *up;
struct refclockproc *pp;
pp = peer->procptr;
up = pp->unitptr;
if (pp->io.fd != -1)
io_closeclock(&pp->io);
if (up != NULL)
free(up);
}
/*
* true_receive - receive data from the serial interface on a clock
*/
static void
true_receive(
struct recvbuf *rbufp
)
{
register struct true_unit *up;
struct refclockproc *pp;
struct peer *peer;
u_short new_station;
char synced;
int i;
int lat, lon, off; /* GOES Satellite position */
/* These variables hold data until we decide to keep it */
char rd_lastcode[BMAX];
l_fp rd_tmp;
u_short rd_lencode;
/*
* Get the clock this applies to and pointers to the data.
*/
peer = rbufp->recv_peer;
pp = peer->procptr;
up = pp->unitptr;
/*
* We get down to business, check the timecode format and decode
* its contents. This code decodes a multitude of different
* clock messages. Timecodes are processed if needed. All replies
* will be run through the state machine to tweak driver options
* and program the clock.
*/
/*
* Clock misunderstood our last command?
*/
if (pp->a_lastcode[0] == '?' ||
strcmp(pp->a_lastcode, "ERROR 05 NO SUCH FUNCTION") == 0) {
true_doevent(peer, e_Huh);
return;
}
/*
* This is less than perfect. Call the (satellite)
* either EAST or WEST and adjust slop accodingly
* Perfectionists would recalculate the exact delay
* and adjust accordingly...
*/
if (lon > 7000 && lon < 14000) {
if (lon < 10000) {
new_station = GOES_EAST;
label = "EAST";
} else {
new_station = GOES_WEST;
label = "WEST";
}
/*
* Adjust the synchronize indicator according to timecode
* say were OK, and then say not if we really are not OK
*/
if (synced == '>' || synced == '#' || synced == '?'
|| synced == 'X')
pp->leap = LEAP_NOTINSYNC;
else
pp->leap = LEAP_NOWARNING;
true_doevent(peer, e_TS);
#ifdef CLOCK_PPS720
/* If it's taken more than 65ms to get here, we'll lose. */
if ((pp->sloppyclockflag & CLK_FLAG4) && up->pcl720init) {
l_fp off;
#ifdef CLOCK_ATOM
/*
* find out what time it really is. Include
* the count from the PCL720
*/
if (!clocktime(pp->day, pp->hour, pp->minute,
pp->second, GMT, pp->lastrec.l_ui,
&pp->yearstart, &off.l_ui)) {
refclock_report(peer, CEVNT_BADTIME);
return;
}
off.l_uf = 0;
#endif
/*
* Stomp all over the timestamp that was pulled out
* of the input stream. It's irrelevant since we've
* adjusted the input time to reflect now (via pp->usec)
* rather than when the data was collected.
*/
get_systime(&pp->lastrec);
#ifdef CLOCK_ATOM
/*
* Create a true offset for feeding to pps_sample()
*/
L_SUB(&off, &pp->lastrec);
/*
* The clock will blurt a timecode every second but we only
* want one when polled. If we havn't been polled, bail out.
*/
if (!up->polled)
return;
/* We only call doevent if additional things need be done
* at poll interval. Currently, its only for GOES. We also
* call it for clock unknown so that it gets logged.
*/
if (up->type == t_goes || up->type == t_unknown)
true_doevent(peer, e_Poll);
if (!refclock_process(pp)) {
refclock_report(peer, CEVNT_BADTIME);
return;
}
/*
* If clock is good we send a NOMINAL message so that
* any previous BAD messages are nullified
*/
pp->lastref = pp->lastrec;
refclock_receive(peer);
refclock_report(peer, CEVNT_NOMINAL);
/*
* We have succedded in answering the poll.
* Turn off the flag and return
*/
up->polled = 0;
return;
}
/*
* No match to known timecodes, report failure and return
*/
refclock_report(peer, CEVNT_BADREPLY);
return;
}
/*
* true_send - time to send the clock a signal to cough up a time sample
*/
static void
true_send(
struct peer *peer,
const char *cmd
)
{
struct refclockproc *pp;
pp = peer->procptr;
if (!(pp->sloppyclockflag & CLK_FLAG1)) {
size_t len = strlen(cmd);
/*
* state machine for initializing and controlling a clock
*/
static void
true_doevent(
struct peer *peer,
enum true_event event
)
{
struct true_unit *up;
struct refclockproc *pp;
pp = peer->procptr;
up = pp->unitptr;
if (event != e_TS) {
NLOG(NLOG_CLOCKSTATUS) {
msyslog(LOG_INFO, "TRUE: clock %s, state %s, event %s",
typeStr(up->type),
stateStr(up->state),
eventStr(event));
}
}
true_debug(peer, "clock %s, state %s, event %s\n",
typeStr(up->type), stateStr(up->state), eventStr(event));
switch (up->type) {
case t_goes:
switch (event) {
case e_Init: /* FALLTHROUGH */
case e_Satellite:
/*
* Switch back to on-second time codes and return.
*/
true_send(peer, "C");
up->state = s_Start;
break;
case e_Poll:
/*
* After each poll, check the station (satellite).
*/
true_send(peer, "P");
/* No state change needed. */
break;
default:
break;
}
/* FALLTHROUGH */
case t_omega:
switch (event) {
case e_Init:
true_send(peer, "C");
up->state = s_Start;
break;
case e_TS:
if (up->state != s_Start && up->state != s_Auto) {
true_send(peer, "\03\r");
break;
}
up->state = s_Auto;
break;
default:
break;
}
break;
case t_tm:
switch (event) {
case e_Init:
true_send(peer, "F18\r");
up->state = s_Init;
break;
case e_F18:
true_send(peer, "F50\r");
/*
* Timecode: " TRUETIME Mk III" or " TRUETIME XL"
* (from a TM/TMD/XL clock during initialization.)
*/
if ( strcmp(pp->a_lastcode, " TRUETIME Mk III") == 0 ||
strncmp(pp->a_lastcode, " TRUETIME XL", 12) == 0) {
true_doevent(peer, e_F18);
NLOG(NLOG_CLOCKSTATUS) {
msyslog(LOG_INFO, "TM/TMD/XL: %s",
pp->a_lastcode);
}
return;
}
up->state = s_F18;
break;
case e_F50:
true_send(peer, "F51\r");
up->state = s_F50;
break;
case e_F51:
true_send(peer, "F08\r");
up->state = s_Start;
break;
case e_TS:
if (up->state != s_Start && up->state != s_Auto) {
true_send(peer, "\03\r");
break;
}
up->state = s_Auto;
break;
default:
break;
}
break;
case t_tcu:
switch (event) {
case e_Init:
true_send(peer, "MD3\r"); /* GPS Synch'd Gen. */
true_send(peer, "TSU\r"); /* UTC, not GPS. */
true_send(peer, "AU\r"); /* Auto Timestamps. */
up->state = s_Start;
break;
case e_TS:
if (up->state != s_Start && up->state != s_Auto) {
true_send(peer, "\03\r");
break;
}
up->state = s_Auto;
break;
default:
break;
}
break;
case t_tl3:
switch (event) {
case e_Init:
true_send(peer, "ST1"); /* Turn on continuous stream */
break;
case e_TS:
up->state = s_Auto;
break;
default:
break;
}
break;
case t_unknown:
if (event == e_Poll)
break;
switch (up->state) {
case s_Base:
if (event != e_Init)
abort();
true_send(peer, "P\r");
up->state = s_InqGOES;
break;
case s_InqGOES:
switch (event) {
case e_Satellite:
up->type = t_goes;
true_doevent(peer, e_Init);
break;
case e_Init: /*FALLTHROUGH*/
case e_Huh:
case e_TS:
true_send(peer, "ST0"); /* turn off TL3 auto */
sleep(1); /* wait for it */
up->state = s_InqTL3;
true_send(peer, "QV"); /* see if its a TL3 */
break;
default:
abort();
}
break;
case s_InqTL3:
switch (event) {
case e_TL3:
up->type = t_tl3;
up->state = s_Auto; /* Inq side-effect. */
true_send(peer, "ST1"); /* Turn on 1/sec data */
break;
case e_Init: /*FALLTHROUGH*/
case e_Huh:
up->state = s_InqOmega;
true_send(peer, "C\r");
break;
case e_TS:
up->type = t_tl3; /* Already sending data */
up->state = s_Auto;
break;
default:
msyslog(LOG_INFO,
"TRUE: TL3 init fellthrough! (%d)", event);
break;
}
break;
case s_InqOmega:
switch (event) {
case e_TS:
up->type = t_omega;
up->state = s_Auto; /* Inq side-effect. */
break;
case e_Init: /*FALLTHROUGH*/
case e_Huh:
up->state = s_InqTM;
true_send(peer, "F18\r");
break;
default:
abort();
}
break;
case s_InqTM:
switch (event) {
case e_F18:
up->type = t_tm;
true_doevent(peer, e_Init);
break;
case e_Init: /*FALLTHROUGH*/
case e_Huh:
true_send(peer, "PO\r");
up->state = s_InqTCU;
break;
default:
msyslog(LOG_INFO,
"TRUE: TM/TMD init fellthrough!");
break;
}
break;
case s_InqTCU:
switch (event) {
case e_Location:
up->type = t_tcu;
true_doevent(peer, e_Init);
break;
case e_Init: /*FALLTHROUGH*/
case e_Huh:
up->state = s_Base;
sleep(1); /* XXX */
break;
default:
msyslog(LOG_INFO,
"TRUE: TCU init fellthrough!");
break;
}
break;
/*
* An expedient hack to prevent lint complaints,
* these don't actually need to be used here...
*/
case s_Init:
case s_F18:
case s_F50:
case s_Start:
case s_Auto:
case s_Max:
msyslog(LOG_INFO, "TRUE: state %s is unexpected!",
stateStr(up->state));
}
break;
default:
msyslog(LOG_INFO, "TRUE: cannot identify refclock!");
abort();
/* NOTREACHED */
}
#ifdef CLOCK_PPS720
if ((pp->sloppyclockflag & CLK_FLAG4) && !up->pcl720init) {
/* Make counter trigger on gate0, count down from 65535. */
pcl720_load(PCL720_IOB, PCL720_CTR, i8253_oneshot, 65535);
/*
* (These constants are OK since
* they represent hardware maximums.)
*/
NLOG(NLOG_CLOCKINFO) {
msyslog(LOG_NOTICE, "PCL-720 initialized");
}
up->pcl720init++;
}
#endif
}
/*
* true_poll - called by the transmit procedure
*/
static void
true_poll(
int unit,
struct peer *peer
)
{
struct true_unit *up;
struct refclockproc *pp;
/*
* You don't need to poll this clock. It puts out timecodes
* once per second. If asked for a timestamp, take note.
* The next time a timecode comes in, it will be fed back.
*/
pp = peer->procptr;
up = pp->unitptr;
if (up->pollcnt > 0) {
up->pollcnt--;
} else {
true_doevent(peer, e_Init);
refclock_report(peer, CEVNT_TIMEOUT);
}
/*
* polled every 64 seconds. Ask true_receive to hand in a
* timestamp.
*/
up->polled = 1;
pp->polls++;
}
#ifdef CLOCK_PPS720
/*
* true_sample720 - sample the PCL-720
*/
static u_long
true_sample720(void)
{
unsigned long f;
/* We wire the PCL-720's 8253.OUT0 to bit 0 of connector 3.
* If it is not being held low now, we did not get called
* within 65535us.
*/
if (inb(pcl720_data_16_23(PCL720_IOB)) & 0x01) {
NLOG(NLOG_CLOCKINFO) {
msyslog(LOG_NOTICE, "PCL-720 out of synch");
}
return (0);
}
f = (65536 - pcl720_read(PCL720_IOB, PCL720_CTR));
#ifdef PPS720_DEBUG
msyslog(LOG_DEBUG, "PCL-720: %luus", f);
#endif
return (f);
}
#endif
