PM5351 Datasheet, PDF (50/393 Pages) PMC-Sierra, Inc – Quad 155 Mbit/s ATM and Packet Over SONET/SDH Physical Layer Device

S/UNI-TETRA
DATASHEET
PMC-1971240
Pin Name
PTPA
PMC-Sierra, Inc.
PM5351 S/UNI-TETRA
ISSUE 7
SATURN USER NETWORK INTERFACE (155-TETRA)
Type Pin
No.
J23
Function
POS-PHY Polled Transmit multi-PHY Packet
Available (PTPA).
PTPA transitions high when a programmable
minimum number of bytes is available in the polled
transmit FIFO (TPAHWM[7:0] register bits). Once
high, PTPA indicates that the transmit FIFO is not
full. When PTPA transitions low, it optionally
indicates that the transmit FIFO is full or near full
(TPALWM[7:0] register bits). PTPA allows to poll
the PHY address selected by TADR[4:0] when
TENB is asserted.
PTPA is tri-stated when either the null-PHY address
(0x1F) or an address not matching the address
space set by PHY_ADR[2:0] is latched from the
TADR[4:0] inputs when TENB is high.
PTPA is only available in POS-PHY packet-level
transfer mode, as selected by the POS_PLVL
register bit. PTPA is tristated in byte-level transfer
mode. PTPA is updated on the rising edge of
TFCLK.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
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