Symmetricom XL-GPS, User Manual

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F111 – J2 Output (Rate, PPO)
For example, to produce a fixed 100 kPPS rate output, enter:
F111 RATE 100KPPS<CR>
XL-GPS responds:
OK<CR><LF>
Single PPO pulse output
For example, to produce a a single pulse with duration of 1 second on January 1, enter:
F111 PPO 001:00:00:00.000000 001:00:00:01.000000 <CR>
XL-GPS responds:
OK<CR><LF>
Or, for example, to produce a single pulse with duration of 1 microsecond on January 1,
enter:
F111 PPO 001:00:00:00.000000<CR>
XL-GPS responds:
OK<CR><LF>
Repetitive PPO pulse outputs
Repetitive PPO pulse output function can be used to produce repetitive pulses from once per
year up to 100,000 per second.
To issue repetitive pulses using PPO, "wildcards" are utilized in the Start Time (and Stop
Time) fields. Through the command line interface, the user may place 'X' (or 'x') in the time
fields of the F111 command. The 'X' (or 'x') character is referred to as the "wildcard" in the
PPO time fields. The most significant non-wildcard-digit in the time field is used to specify the
Start (or Stop) Time of the repetitive pulses, which in turn specifies the pulse width of the
repetitive pulses. The least significant "wildcard" character (the one to the immediate left of
the most significant non-wildcard-digit) specifies the period of repetition.
When specifying repetitive rates, the Start Time must include the same number of significant
digits as the Stop Time or an ambiguous output may occur.
Any time the clock reads a new time that matches the specified least significant digits, a pulse
either starts or stops. For example, the following string produces a pulse at midnight every
day with a “1” in the least significant digit:
F111 PPO XX1:00:00:00.000000 XX1:00:00:01.000000<CR>
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