RELEASED
PM7350 S/UNI-DUPLEX
DATA SHEET
PMC-1980581
ISSUE 5
DUAL SERIAL LINK PHY MULTIPLEXER
Ball
Ball
Name
Type
No. Function
High Speed LVDS Links
ICA
I/O
A3 The Input Cell Available (ICA) signal provides cell-
level flow control. ICA’s direction depends on the
state of the IMASTER input.
As a SCI-PHY/Utopia bus master (IMASTER = 1,
IANYPHY = 0) the S/UNI-DUPLEX polls up to 32
PHYs using the PHY address signals IADDR[4:0].
A PHY device being addressed by IADDR[4:0] is
expected to indicate whether or not it has a
complete cell available for transfer by driving ICA
during the clock cycle following that in which it is
addressed. When a cell transfer is in progress, the
S/UNI-DUPLEX will not poll the PHY device which
is sending the cell so PHY devices need not
support the cell availability indication during cell
transfer. The selection of a particular PHY device
from which to transfer a cell is indicated by the state
of IADDR[4:0] during the last cycle IENB is high.
As a bus slave (IMASTER = 0) the S/UNI-DUPLEX
indicates the ability to accept additional cells via the
ICA output. When IAVALID is sampled high in SCI-
PHY or low in Any-PHY configuration, ICA is
asserted if the cell FIFO for the logical channel
addressed by IADDR[4:0] has at least one empty
cell buffer. If the FIFO is full, ICA is deasserted. If a
cell transfer is in progress that will fill a logical
channel FIFO, ICA will also be deasserted. When
IAVALID is sampled low in SCI-PHY or high in Any-
PHY configuration, ICA becomes high impedance.
ICA is delayed by an additional clock cycle in Any-
PHY configuration. The buffer status for the
particular logical channel involved is stale for a
maximum of 16 cycles after the start of the cell
transfer when using a 8 bit bus or 12 cycles when
using a 16 bit bus. Therefore, the master should
refrain from polling that logical channel in the
interim.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
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PMC [ PMC-SIERRA, INC ]
