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Format 2

Provides a time data stream with millisecond resolution. The Format 2 data stream consists of indicators for time sync status, time quality, leap second and Daylight Saving Time. Time data reflects UTC time and is in the 24-hour format. Format 2 data structure is:


CR LF IQYY ^ DDD ^ HH:MM:SS.sss ^ LD


CHARACTER DESCRIPTOR:
CR Carriage Return
LF Line Feed
I Time Sync Status (space, ?, *)
Q Quality Indicator (space, A, B, C, D)
YY Year without century (02, 03, 04 etc.)
^ space separator
DDD Day of Year (001-366)
HH Hours (00-23)
: Colon separator
MM Minutes (00-59)
SS Seconds (00-60)
. Decimal Separator
sss Milliseconds (000-999)
L Leap Second Indicator (space, L)
D Daylight Savings Time indicator (S,I,D,O)

Example: ?A02 271 12:45:36.123 S


Sync Status The clock has lost time sync. The inaccuracy code of "A" indicates the expected time error is <10 milliseconds.
Date Year 02, Day 271
Time 12:45:36.123 UTC time, standard time.

Notes

  1. The leading edge of the first character (CR) marks the on-time point of the data stream.
  2. The time sync status character I is defined as described below:
    (Space) = Whenever the front panel Time Sync lamp is green.
    ? = When the receiver is unable to track any satellites and the Time Sync lamp is red.
    * = the receiver time is derived from the battery backed clock or set manually through the Serial Setup Interface.
  3. The quality indicator Q provides an inaccuracy estimate of the output data stream. When the receiver is unable to track the reference, a timer is started. The table below lists the quality indicators and the corresponding error estimates based upon the internal oscillator stability and the time elapsed tracking no satellites. The timer and the quality indicator reset when the receiver requires its reference.

    TYPICAL NETCLOCK/GPS INACCURACY
    Inaccuracy Code Time Error (mSec) Time Since Unlock (Hours)
    Space <1 Locked
    A <10 <10
    B <100 <10
    C <500 <10
    D >500 >500
  4. The Daylight Saving Time indicator D is defined as:
    S During periods of standard time for the selected DST schedule.
    I During the 24-hour period preceding the change into DST
    D During periods of Daylight Saving Time for the selected DST schedule
    O During the 24-hour period preceding the change out of DST

Back to:
ASCII Time Code Format 1
Next to:
ASCII Time Code Format 3
 
 
   
 
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