Symmetricom Time Server - Manual (Page 70)

4-56 TimeVault™ User’s Manual 6000-100Ch4.fm Rev. D
Chapter 4: Serial or Telnet I/O Functions Function Commands
4.3.5 F60 – Satellite List Request
Use Function 60 to list current satellites and to see the relative signal strength of satellites
the unit is tracking. Signal strength is given in units in the range of 0 to +25.
The unit monitors five variables: the prn number, good/bad, enabled/disabled, tracked, and
current.
To request the list, send the following command:
F60
where
F = ASCII character F
60 = function number
= input line terminator
The unit responds:
F60prn NNgoodenabledtrackedcurrent
siglevel= +
where
prn NN = pseudo-random number; the prn number is a unique
identifier for a particular satellite’s communication
path; for example, satellite 3 might have the prn
number 15; if that satellite is recalled to Earth and
replaced by satellite 42, the communication path of
satellite 42 might also be assigned prn 15
enabled/disabled = “Enabled” refers to a factory default configuration
value that allows the GPS to track all satellites on
the F60 list
good/bad = “Good” means all three of the following apply:
• the satellite is visible, and
• the satellite’s ephemeris and almanac data report
the satellite’s health as “good”, and
• the satellite reports its own health as “good”
“Bad” means at least one of the following applies:
• the satellite is not visible, or
• the satellite’s ephemeris and almanac data report
the satellite’s health as “bad”, or
• the satellite reports its own health as “bad” (for
example, during maintenance periods)
tracked = “Tracked” means that the unit is tracking this
particular satellite
current = “Current” means that the unit is both tracking this
satellite and using the satellite’s communication to
calculate accurate time; an example from the list is
prn 3
= line terminator