PM73121ꢀAAL1gator II
Data Sheet
PMC-Sierra, Inc.
PMC-980620
,VVXHꢀꢁ
AAL1 SAR Processor
no pointer, set T_CHAN_UNSTRUCT = 1 in the QUEUE_CONFIG word of the T_QUEUE_
TBL.
4. The TALP fills the rest of the cell payload with data and/or signaling information. The T_
CHAN_ALLOC table (refer to section 7.6.8 “T_QUEUE_TBL” on page 134) determines
which channels are dedicated to which queue. If a bit is set, the channel represented by that bit
is assigned to that queue. The TALP successively writes the data from the marked channels
into the UTOPIA interface. A queue-based parameter, BYTES_PER_CELL, decides when
enough payload bytes have been obtained. If this number is fewer than 47, then the remaining
bytes for the cell are loaded with P_FILL_CHAR. This implies that because of the presence of
the structure pointer, the number of fill bytes will not be constant for structured data queues.
5. The structure used for signaling is determined by the mode of the line and the value of
E1_WITH_T1_SIG. Normally the signaling structure will follow the mode of the line.
However, if the line is in E1 mode and E1_WITH_T1_SIG is set, then a T1 signaling
structure is used. This means that for a single DS0, signaling is inserted after 24 data
bytes instead of after 16 data bytes. If data is to be sent from the data queue, this process
continues byte-by-byte while updating pointers and counters until one of the following
occurs:
•
•
The cell is complete.
The last data byte for the last frame of the multiframe has been set.
6. When signaling information is to be sent, data is obtained from the signaling locations of the
multiframe, with the help of the channel allocation table (T_CHAN_ALLOC). This process
proceeds byte-by-byte until one of the following occurs:
•
•
The cell is complete.
All signaling nibbles for all channels assigned to the queue have been sent.
ꢃꢉ
PMC [ PMC-SIERRA, INC ]
