PM73121ꢀAAL1gator II
Data Sheet
PMC-Sierra, Inc.
PMC-980620
,VVXHꢀꢁ
AAL1 SAR Processor
and Figure 21 shows the contents of the transmit signaling buffer for the different signaling
modes.
0
15
Bit
Word 0
1
CH1
CH0
3
5
2
4
2
3
4
5
7
9
6
8
11
13
15
10
12
14
6
7
8
9
17
19
16
18
10
21
23
20
22
11
12
13
24
25
27
26
14
15
29
28
CH30
CH31
NOTE: The upper nibble of each byte is 0.
T1 format uses word addresses 0 to 11.
Figure 21. SDF-MF Format of the T_SIGNALING_BUFFER (T1 and E1 Modes)
3.1.1 Transmit Conditioning
The T_COND_DATA structure allows conditional data to be defined on a per-DS0 basis. The
structure T_COND_SIG allows conditioned signaling to be defined on a per-DS0 basis. The TX_
COND bit in the T_QUEUE_TBL allows the cell building logic (described in section 3.3 “Trans-
mit Adaptation Layer Processor (TALP)” on page 38) to be directed to build cells from the condi-
tioned data and signaling. The TX_COND bit can be set on a per-queue basis.
3.1.2 Transmit Signaling Freezing
Signaling freezing is a required function when transporting CAS. This function holds the signal-
ing unchanged when the incoming line fails. The PMC-Sierra framers provide this function. If a
framer is used that does not support signaling freezing, this function must be provided externally.
3.1.3 SRTS for the Transmit Side
NOTE: The AAL1gator II uses Bellcore’s patented SRTS clock recovery technique. Refer to
the NOTE on page 172 for additional information regarding Bellcore’s SRTS patent.
ꢂꢁ
PMC [ PMC-SIERRA, INC ]
