PM7346 S/UNI-QJET
DATASHEET
PMC-960835
ISSUE 6
SATURN QUAD USER NETWORK INTERFACE FOR J2, E3, T3
PMC-SIERRA, INC. PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA INC., AND ITS CUSTOMERS’ INTERNAL USE
359
error mask, that is the binary value sampled on TOH in the EM byte location is
not inserted directly into the transmit overhead but, rather, the value is XORed
with the calculated BIP-8 and inserted in the transmit overhead. Asserting
TOHINS during the “gaps” in the TOH stream has no effect.
Figure 58
- Transmit G.751 E3 Overhead
TOHFP[x]
TOHCLK[x]
TOH[x]
G.751 Frame Period
RAI Nat C11 C21 C31 C41 C12 C22 C32
C13 C23 C33
J1
J2
J3
C42
C43
J4
TOHINS[x]
RAI
...
...
...
30 cycles
...
The Transmit G.751 E3 Overhead diagram (Figure 58) shows the insertion of
G.751 overhead bits RAI, the National Use Bit, and the stuff indication and
opportunity bits using the TOH input, along with the overhead insertion enable
input, TOHINS. The TOHFP output is set to logic 1 once per G.751 E3 frame
period (during the RAI bit position). In Figure 58, the data sampled on TOH
during the RAI, National Use, or stuff bit positions while TOHINS is logic 1 is
inserted into the G.751 E3 overhead bits in the transmit stream.
The PYLD&JUST bit in the E3 TRAN Status and Diagnostics Options register
has no affect on the insertion of the justification service and the tributary
justification bits through the TOH and the TOHINS inputs.
Figure 59
- Transmit J2 Overhead
...
...
...
...
...
...
...
...
m1
0
0
1
1
e5
e4
e3
e2
e1
TS97
TS98
TS97
TS98
TS97
J2 Multi-Frame Period
TOHFP[x]
TOHCLK[x]
TOH[x]
TOHINS[x]