RELEASED
PM73123 AAL1GATOR-8
DATASHEET
PMC-2000097
ISSUE 2
8 LINK CES/DBCES AAL1 SAR
MODE
SYS_CLK=38.88 MHz SYS_CLK = 45 MHz
16
21
22
15
19
20
T1 SDF-MF
E1 SDF-FR
E1 SDF-MF
9.2.1.4 Transmit FIFO (TALP_FIFO)
This block contains an 8 cell FIFO which buffers cells going out to the UTOPIA
Interface block.
The UTOPIAI polls the A1SP block to determine if the A1SP has cells available
in the TALP_FIFO. If the TUTOPIA FIFO has room for a cell, the A1SP block is
selected, a cell is read from the TALP FIFO, and moved into the TUTOPIA FIFO.
9.2.1.5 Local Loopback Block(LOC_LPBK)
The AAL1gator-8 supports local loopback of cells. Local loopback is when a cell
generated by TALP is looped back to RALP instead of being sent out to the
UTOPIA bus via the TALP FIFO.
When LOOPBACK_ENABLE is set in the TRANSMIT_CONFIG register, cells for
that queue will be looped back to the RALP block instead of being transmitted
toward the UTOPIA bus. Since this bit is configurable on a per queue basis it can
be used during normal operation to loop back individual time slots, groups of
time slots on a given line or even entire lines. The cells, which are looped back,
are stored in a separate 3 cell FIFO that RALP can read. The loopback FIFO will
have higher priority to prevent the transmitter from backing up. See Figure 32 for
architecture of the local loopback.
Note: Remote loopback is also supported in the AAL1gator-8, but it is
performed in the UTOPIAI block.
PMC-SIERRA, INC. PROPRIETARY AND CONFIDENTIAL
101
PMC [ PMC-SIERRA, INC ]
