PMC-Sierra, Inc.
PRELIMINARY
PM5381 S/UNI-2488
DATASHEET
PMC-2000489
ISSUE 1
SATURN USER NETWORK INTERFACE FOR 2488 MBIT/S
Figure 15: STS-48c (STM-16-16c) on TTOH
First order of transmission
A1 A1 A1 A1 A1 ... A1 A2 A2 A2 A2 A2 ... A2 J0 Z0 Z0 Z0 Z0 ... Z0
B1
D1
...
...
E1
D2
...
...
F1
D3
...
...
H1 H1 H1 H1 H1 ... H1 H2 H2 H2 H2 H2 ... H2 H3 H3 H3 H3 H3 ... H3
B2 B2 B2 B2 B2 ... B2 K1
...
...
...
...
K2
D6
...
...
...
...
...
D4
D7
...
...
...
D5
D8
D9
D10
D11
D12
S1 Z1 Z1 Z1 Z1 ... Z1 Z2 Z2 M1 Z2 Z2 ... Z2 E2
Unused bytes
National bytes Z0 Z0 or National bytes
Note, only the overhead from the first STS-12 (STM-4) of the STS-48c (STM-16c) can be
sourced. Overhead from the other three STS-12s (STM-4s) are internally generated assigned or
are assigned default values as described below.
The TRMP also inserts most of the transport overhead bytes from internal registers. Since there
is multiple sources for the same overhead byte, the TOH bytes must be prioritised according to
Table 4 before being inserted into the data stream.
Table 4: TOH insertion priority
BYTE
HIGHEST
priority
LOWEST
priority
A1
76h
(A1ERR=1)
F6h
(A1A2EN=1)
TTOH
(TTOHEN=1)
A1 pass through
A2 pass through
J0 pass through
A2
28h
(A1A2EN=1)
TTOH
(TTOHEN=1)
J0
STS-1/STM-0 #
(J0Z0INCEN=1)
J0[7:0]
(TRACEEN=1
)
J0V
(J0REGEN=1)
TTOH
(TTOHEN=1)
Z0
B1
STS-1/STM-0 #
(J0Z0INCEN=1)
Z0V
(Z0REGEN=1)
TTOH
(TTOHEN=1)
Z0 pass through
Calculated B1
xor TTOH
Calculated B1
xor B1MASK
(TTOHEN=1 &
B1MASKEN=1)
TTOH
(TTOHEN=1 &
B1MASKEN=0)
E1
F1
E1V
(E1REGEN=1)
TTOH
(TTOHEN=1)
E1 pass through
F1 pass through
F1V
TTOH
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73
PMC [ PMC-SIERRA, INC ]
