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S/UNI-JET Data Sheet
Released
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990267, Issue 3
47
Pin Name
Type
Pin
No.
Function
RPRTY
Output
R18
The Receive Parity (RPRTY) signal indicates the parity
of the RDAT bus.
The S/UNI-JET can be configured to operate with an 8-
bit wide or 16-bit wide ATM data interface via the ATM8
input pin. In the 8-bit mode, RPRTY reflects the parity of
RDAT[7:0]. In the 16-bit mode, RPRTY reflects the parity
of RDAT[15:0].
Odd or even parity selection is made using the RXPTYP
register bit.
RPRTY is tri-stated when either the null-PHY address
(7H) or an address not matching the address space set
by PHY_ADR[2:0] is latched from the RADR[2:0] inputs
when RENB is high.
RSOC
Output
M17
The Receive Start of Cell (RSOC) signal marks the start
of cell on the RDAT bus. RSOC marks the start of the
cell on the RDAT bus.
RSOC is tri-stated when either the null-PHY address
(7H) or an address not matching the address space set
by PHY_ADR[2:0] is latched from the RADR[2:0] inputs
when RENB is high.
RENB
Input
N18
The Receive Multi-PHY Read Enable (RENB) signal is
used to initiate reads from the receive FIFO.
When sampled low using the rising edge of RFCLK, a
byte is read (if one is available) from the receive FIFO
selected by the RADR[2:0] address bus and output on
the RDAT bus. When sampled high using the rising edge
of RFCLK, no read is performed and RDAT[15:0],
RPRTY, and RSOC are tri-stated, and the address on
RADR[2:0] is latched to select the device or port for the
next ATM FIFO access.
RENB must operate in conjunction with RFCLK to
access the FIFOs at a high enough rate to prevent FIFO
overflows. The ATM layer device may de-assert RENB at
anytime it is unable to accept another byte.
RADR[2]
RADR[1]
RADR[0]
Input
P19
N17
P18
The Receive Address (RADR[2:0])] bus is used for
device selection and device polling in accordance with
the Utopia Level 2 standard. When RADR[2:0] is set to
the same value as the PHY_ADR[2:0] inputs than the
receive interface of this S/UNI-JET is either being
selected or polled.
Note: The null PHY address 7H is an invalid address and
cannot be used to select the S/UNI-JET.
RADR[2:0] is sampled on the rising edge of TFCLK.