Operating Instructions PCIe TS
Page 15
Pleas note: Do not set values less than 0.5 seconds. If the system time is hard set, a
difference of some ms occurs, which will then be readjusted. This difference is produced by
the Windows system. If the selected value is too low, this difference might cause a hard set,
which will cause another hard set, etc.
•
“Difference for error”: The difference between the sys
tem time and the LTC in seconds,
from which on the LTC will be rejected as not plausible. If system time and LTC have been
synchronized o
nce (e.g. with the “Hard set” button), no considerable differences between
these two times will occur during continuous operation. If the PC is switched off, the system
time will continue counting battery-powered with an accuracy of 10
-5
to 10
-4
approx. This
way a difference will accumulate, up to a maximum of 9 seconds per day, depending on
the circumstances. Please take this into consideration when setting the difference.
Differences above this setting may hint at a faulty LTC. Hence, this setting serves to detect
such faults. If every LTC shall be accepted, this error detection may be disabled by setting
0.00.
•
“Sync
+”, “
Sync -
”:
The adjusting speed to accelerate (Sync +) or moderate (Sync -) the
system clock. A setting of 2000 effects an adjustment of approximately 20ms per second. A
difference of one second (1000ms) will be readjusted within 1000ms / 20ms = 50
seconds. The higher the values, the faster the system clock will catch up with the LTC.
•
“LTC board base address”:
If more than one PCL board is installed, the PCIe TS board can
be selected here. If the PCIe TS is the only PCL board installed, this parameter is always 1.
•
“Format of date”:
Beside the time, date information from the LTC can be used. To do this,
the format of the date has to be defined:
Format
User bits
Date State Time zone
0 None
Not used
1 MTD
MTD
2 Date
User = XX DD MM YY
3 Status
User = SS DD MM YY
4 EBU I29
User = EBU Tech. I29-1995 (BBC)
5 Date-2
User = DD MM YYYY
6 Date-3
User = YY MM DD XX
7 Date-4
User = XX YY MM DD
8 Date-5
User = X YY MM DD X
9 Date-6
User = DD MM YY XX
Meaning of symbols: SS = state, DD = day, MM = month, YY two-digit year, YYYY = four
digit year, X = unused. The format number is the same as the user mode of the Plura LTC
generator Rubidium GT.
•
“Time
zone”:
The LTC source does not necessary has been generated in the same time
zone the PC is running in. It is possible to have the PC running in Central Europe Time
(CET, with daylight saving time switching), but the LTC running in UTC. The setting
“
Time
zone
” spe
cifies how to handle time zones:
−
“From LTC Status”:
The time zone information is read from the LTC. This is only possible
in date formats 1 and 3.
−
“Same as PC”:
The LTC is running in the same time zone as the PC. That means that the
LTC does the same daylight switching as the PC.
−
“UTC”:
The LTC is running in UTC.
