RELEASED
PM73123 AAL1GATOR-8
DATASHEET
PMC-2000097
ISSUE 2
8 LINK CES/DBCES AAL1 SAR
Figure 20 SDF-MF E1 with T1 Signaling Format of the
T_SIGNALING_BUFFER
Byte Address
Multiframe
Channel 30
ABCD
Channel 31
ABCD
Channel 0
ABCD
Channel 1
ABCD
0
3
9.2.1.1.1 Transmit Conditioning
The T_COND_DATA structure allows conditional data to be defined on a per-
DS0 basis and the T_COND_SIG structure 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 9.2.1.3 Transmit Adaptation Layer
Processor (TALP) on page 96) to be directed to build cells from the conditioned
data and signaling. To control whether conditioned data, conditioned signaling, or
both is used, set TX_COND_MODE in the TX_CONFIG register to the
appropriate value. The TX_COND bit and TX_COND_MODE bits can be set on a
per-queue basis.
By having independent control over whether signaling or data is conditioned, it is
possible to substitute the signaling which is carried in the CAS bits across the
ATM network while still passing the data received off the line. This is useful for
applications that may not be receiving the signaling with the data.
For HS_UDF mode the HS_TX_COND bit needs to be set in the HS_LIN_REG
register. When this bit is set cells with an all ones pattern will be generated. The
CMD_REG_ATTN bit needs to be written to a ‘1’ after the HS_TX_COND bit is
set for this function to take affect.
Under certain alarm conditions such as Loss of Signal (LOS), an Alarm Indication
Signal (AIS) needs to be transmitted downstream. This means that cells need to
be generated which carry an AIS pattern. The AAL1gator-8 does not do any
alarm processing and is dependent on the external framer for this functionality.
The framer would notify the processor of any alarm conditions and then the
processor would switch a particular queue from normal mode to a conditioned
mode by setting the TX_COND bit in the T_QUEUE_TBL.
Most AIS signals are an all ones pattern, so cells with this pattern can be
generated by setting T_COND_DATA to “FF”x and T_COND_SIG to “F”x. In E3
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