PM7344 S/UNI-MPH
DATA SHEET
PMC-950449
ISSUE 6
MULTI-PHY USER NETWORK INTERFACE
Pin Name
Type
Pin Function
No.
TWA[0]
Input
64
Transmit Write Address LSB (TWA[0]). The
TWA[0] signal is available on this pin when input
MPHEN is high. TWA[0] is used (along with
TWA[1]) to select the FIFO (and hence port) that
is written to using the TWRMPHB signal.
TWA[0] is sampled on the rising edge of TFCLK
together with TWRMPHB.
TWRENB[2
]
Transmit Write Enable PHY #2 (TWRENB[2]).
The TWRENB[2] signal is available on this pin
when input MPHEN is low. TWRENB[2] is used
to initiate writes to the transmit FIFO of PHY #2.
When sampled low using the rising edge of
TFCLK (and the remaining three TWRENBs
remain high), a byte is written to PHY #2's
synchronous FIFO. When sampled high using
the rising edge of TFCLK, no write is performed.
TWRENB[2] must operate in conjunction with
TFCLK to access the FIFOs at a high enough
instantaneous rate as to avoid FIFO overflows.
The ATM layer device may deassert
TWRENB[2] at anytime it is unable to provide
another byte.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
32
PMC [ PMC-SIERRA, INC ]
