VeEX RXT3900, User Manual

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Summary tab, which is the same as the summary section of Overhead Analyzer .
Overhead Generator
Programming most overhead bytes is possible using the OH Generator feature, however dedicated
test functions are available for Pointer Tasks, Payload Labels, Trace Identifier, APS Testing, TCM
testing.
In some instances, more advanced editing is possible using the dedicated functions.
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10.1.4 Pointer Tasks
Tap the Pointer Tasks icon from the Home menu to display the Pointer testing screens.
10.1.4.1 Pointer Analysis
Pointers keep SDH signals synchronous by compensating for timing differences without having to use stuffing bits. Pointers are
allowed to move up or down every three frames, however the actual rate should be slower. The Administrative Unit (AU) and the
Tributary Unit (TU) each has its own pointer and the unit has two tabs for displaying the values and measurements.
For AU pointers:
SS bits – Displays bits 5 and 6 of the H1 byte to indicate SDH [10], SONET [00], Unknown [01] and [11] signal type
Pointer value – Displays the H1 and H2 values (addresses) indicating the offset in bytes between the pointer and
first byte of the AU-n
LOP (Loss of Pointer)
PJE and NJE
NDF or New Data Flag. NDF is enabled when all bits match “1001” (or "0001", "1101", "1011" and "1000") and is
disabled when all bits match "0110" (or "1110", "0010", "0100", "0111").
Difference and Sum
Implied Offset [ppm]
Analysis > AU tab
RXT-3900 e-Manual D07-00-111P Rev A00