VSC6134
Datasheet
A block diagram of the LOH generator is shown in the following figure.
Figure 11. LOH Generator Functional Block Diagram
Bypass
Mux
S1, E2,
K1/K2, and
Reserve
Bytes
M0/M1
Insert
Line DCC
Insertion
AIS-P
Insertions
Insertion
B2 Insert/
Corruption
Line Overhead Generator MPU Interface
2.4.1
AIS-P Generator
Path AIS (AIS-P) is generated by setting all bytes, except section and line overhead (but including H1,
H2 bytes) to all ones. The AIS-P condition is activated when the SP_AIS_L, SP_LOF, SP_LOS, or
SP_LOC conditions are detected in the same generation path. Each of these conditions can be
provisionally enabled or disabled from AIS-P generation using their respective configuration bits
AISP_AISL_EN, AISP_LOF_EN, AISP_LOS_EN, and AISP_LOC_EN.
Table 8.
Line Overhead Generator Mode Functions
VSC6134 Mode Is Section Terminator
(SONET_SL_MODE = 1)
VSC6134 Mode Is Line Terminator
(SONET_SL_MODE = 0)
In Fail Condition? (LOS or
LOF or LOC or AIS-L)
YES
NO
No AIS-P generation. Source each line
overhead byte if provisioned by
respective source configuration bits.
Generate AIS-P if provisioned to do
so. Source each line overhead byte if
provisioned by respective source
configuration bits.
No AIS-P generation. Source each line
overhead byte if provisioned by
respective source configuration bits.
No AIS-P generation. Source each
line overhead byte if provisioned by
respective source configuration bits.
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VMDS-10185 Revision 4.0
July 2006