5: Function Reference
F71 – Oscillator Statistics
Use F71 to display the phase, frequency offset, drift rate, and DAC value of an internal or
optional external oscillator.
Definitions:
The phase is the instantaneous error in seconds between the oscillator and the control loop
zero servo point. The frequency offset is computed using an averaging time that is equal to
the effective averaging time of the oscillator controller. The oscillator Drift Rate is computed
using a 24-hour average and is the daily Drift Rate of the oscillator. The oscillator DAC value
is the signed 16-bit integer that controls the DAC output voltage. It ranges from 0 to 65536.
Command Line
To display the F71 settings, enter:
F71<CR>
F71 responds using the following format:
F71<S>phase=<SIGN><MULT>E<SIGN><EXP><S>s<S><S>offset=<SIGN>
<MULT>E<SIGN><EXP><S><S>drift=<SIGN><MULT>E<SIGN><EXP>/DAY
<S><S>DAC=<SIGN><INT><CR><LF>
Note: The display example above will be one unbroken line. It is broken here into three lines
for demonstration purposes.
where:
F
= ASCII string indicating function F71
<S>
= ASCII space character one or more.
<MULT>
= multiplier, 4 digits with decimal point.
E
= ASCII character E for exponent.
s
= ASCII character s for seconds abbreviation
<SIGN>
= - for negative or <S> for positive.
<EXP>
= 2 digit exponent.
/DAY
= ASCII characters, units of Drift Rate
<INT>
= integer, 5 digits
<CR>
= carriage return.
<LF>
= line feed.
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