Orolia Spectracom VelaSync 1232, User Manual

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Code digit (Binary 1): 50 millisecond duration.
Position identifier: 80 millisecond duration.
Reference marker: 80 millisecond duration, 1 per 10 seconds. The reference marker
appears as two consecutive position identifiers. The second position identifier or ref-
erence marker is the on-time point for the succeeding code word.
Figure 5-2:
IRIG E time code description
Additional information
The beginning of each 10 second time frame is identified by two consecutive 80 ms ele-
ments (P
0
and P
R
). The leading edge of the second 80 ms element (P
R
) is the "on time"
reference point for the succeeding time code. 1PPS position identifiers P
0
, P
1
… P
9
(80 ms
duration) occur 0.1 s before 1PPS "on time" and refer to the leading edge of the suc-
ceeding element.
The time code word and the control functions presented during the time frame are pulse-
width coded. The binary "zero" and index markers have a duration of 20 ms, and the binary
"one" has a duration of 50 ms. The leading edge is the 10 pps "on time" reference point for
all elements.
The binary coded decimal (BCD) time-of-year code word consists of 26 digits beginning at
index count 6. The binary coded subword elements occur between position identifiers P
0
and P
5
(3 for seconds; 7 for minutes; 6 for hours; 10 for days) until the code word is
230 VelaSync 1232 User Manual
APPENDIX