Safran SecureSync 2400 User Manual page 610

APPENDIX
1. Time frame: 1.0 seconds.
2. Code digit weighting:
3. Code word structure:
The table below lists the Control Function Field and the function of each ele-
ment.
594
A. Binary Coded Decimal time-of-year.
Code word - 30 binary digits.
Seconds, minutes hours, and days.
Recycles yearly.
B. Straight Binary Seconds time-of-day.
Code word - 17 binary digits.
Seconds only, recycles daily.
BCD: Word seconds digits begin at index count 1. Binary coded ele-
ments occur between position identifier elements P0 and P5 (7 for
seconds, 7 for minutes, 6 for hours, and 10 for days) until the code
word is complete. An index marker occurs between decimal digits in
each group to provide separation for visual resolution. Least sig-
nificant digit occurs first.
CF: IRIG formats reserve a set of elements known as Control Func-
tions (CF) for the encoding of various control, identification, or other
special purpose functions. IRIG B has 27 Control Functions located
between elements 50 and 78. The SecureSync uses the Control Func-
tions to encode year information and time synchronization status.
Element 55 is the time synchronization status bit. Element 55 is a Binary 1
when the unit is in sync, and a Binary 0 when it is not.
Year information consists of the last two digits of the current year (i.e. 97,
98, 99 etc.). Elements 60 through 63 contain the binary equivalent of year
units. Elements 65 through 68 contain the binary equivalent of tens of
years. In keeping with IRIG formats, the least significant bit occurs first. All
unused Control Functions are filled with a space (Binary 0).
SBS: Word begins at index count 80. Seventeen Straight Binary Coded ele-
ments occur with a position identifier between the 9th and 10th binary
coded elements. Least significant digit occurs first.
SecureSync 2400 User Manual