EXFO FTB-8510B Guia Del Usuario página 977

The following controls are available with SONET/SDH Intrusive through
mode only:
The Overwrite check box when selected, allows the generation of the
selected byte. The byte can be selected by clicking on its blue label.
The byte having its Overwrite check box selected will have its
hexadecimal value on a yellow background. A byte having its
hexadecimal value with a gray background cannot be overwritten.
The Overwrite LED indicates if there is any byte in any timeslot having
the Overwrite check box selected (LED is green) or not (LED is gray).
Disable All allows to clear the Overwrite check box for all bytes.
The following overhead byte values are displayed in hexadecimal format.
However, a common field allows to see the value of specific byte in binary
format. Click on the blue label of a byte and its binary value will be
displayed in the common field beside the STM-1 Channel selection.
H1 and H2: Pointer
H3: Pointer Action
B2: BIP-8
K1 and K2: Automatic Protection Switching (APS)
D4 through D12: Data Communications Channel (DCC)
S1: Synchronization Status.
M0 or M1
M0: REI-L [STM-1 channel 1 of a STM-0e signal; STM-1 channel 2 of an
STM-64/STM-256 signal]
M1: REI-L [STM-1 channel 1 of a STM-1e or STM-1o signal; STM-1
channel 3 of an STM-4/16/64/256 signal]
Undefined "--" for all other timeslots not covered by M0 and M1.
E2: Orderwire
SONET/SDH Application
Multiplex Section OH TX/RX (SDH)
SDH Tabs
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