Arbiter Systems 1088A, Operation Manual

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8.2 Event Inputs 67
Where: “nnn” = event number (001 to 200)
“ddd” = day of year of the event (1 to 366)
“hh” = hour of the event (00 to 23)
“mm” = minute of the event (00 to 59)
“ss.sssssss” = second and fractional seconds of the event (e.g. 59.9999999)
Press the UP or DOWN key to scroll through all events presently stored in the event time buffer.
After exiting and re-entering the event display mode, the first event data displayed for a given
channel will correspond to the same event number as was last displayed for that channel. However,
the data itself may be changed if it has been overwritten.
To clear the event buffer, press the EVENT/DEVIATION key again, while viewing Event data.
This will cause the display to issue the following prompt:
CLEAR EVENT (A)?
UP=YES DOWN=NO
NOTE: If the event capture channel is not configured for event time recording, it will not display
the CLEAR EVENT prompt.
Clocks display the CLEAR EVENT prompt only if the event capture channel was previously
configured for event time recording. Press ENTER during this display to delete all of the records
in the event buffer, and to allow recording of new event times, starting with event number 001.
If the event capture channel is configured for 1–PPS Deviation, the readout will display the deviation
of the 1–PPS input signal. In this case, the readout display will have the format:
A 1 PPS
±
XXXXX.XX µ S
SIGMA: XXXXX.XX µ S
Where:
1. The top number is the mean (average) value of the most recent 16 records in the event buffer,
and represents the mean deviation (in microseconds) of the measured 1–PPS signal from the
GPS 1–PPS signal. A negative number means the applied 1–PPS signal is early, i.e. before
on-time, and a positive number means it is late, i.e. after on-time.
2. The bottom number is the standard deviation (sigma) of the values of the 16 samples.
8.2.8 RS-232C Event Trapping
The event capture channel of the Model 1088B can be configured to capture one or more events via
the RS-232C Serial Interface. The time mark for a captured event will correspond to the leading
edge of the start bit of the first character in the RS-232C signal. This event mode can be both
armed and interrogated for data over the RS-232C interface, allowing automated synchronization
of an external computer or system.