PM5381-BI PMC-Sierra, Inc., PM5381-BI Datasheet - Page 61

• Manufacturer Part Number: PM5381-BI
• Description: ATM UNI, Single Channel ATM PHY Interface for 2488.32Mbps
• Manufacturer: PMC-Sierra, Inc.

Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-2000489, Issue 4
Pin Name
RCA
RVAL
RERR
REOP
RMOD[1]
RMOD[0]
Type
Output
Output
Output
Output
Output
Pin
No.
U30
U30
T29
P30
T28
T27
Function
The UTOPIA receive cell available (RCA) signal provides
direct status indication when a cell is available in the receive
FIFO.
RCA is updated on the rising edge of RFCLK.
The POS-PHY receive data valid (RVAL) signal indicates the
validity of the receive data signals. When RVAL is high, the
receive signals RDAT[31:0], RPRTY, RSOP, REOP,
RMOD[1:0], and RERR are valid. When RVAL is low, all
receive signals are invalid and must be disregarded.
RVAL will be high when there is valid data on the RDAT[31:0]
bus. RVAL will transition low when the FIFO does not have
data to give. RVAL will remain low until a programmable
minimum number of bytes or an end-of-packet (EOP) exists in
the receive FIFO. The threshold is configurable.
RVAL is updated on the rising edge of RFCLK.
The POS-PHY receive error (RERR) signal indicates that the
current packet is invalid due to an error such as invalid FCS,
excessive length or received abort. RERR may only assert
when REOP is asserted marking the last word of the packet.
RERR is only used in POS-PHY mode and is updated on the
rising edge of RFCLK.
The POS-PHY receive end of packet (REOP) signal marks
the end of packet on the RDAT[31:0] bus. It is legal for RSOP
to be high at the same time REOP is high. REOP is set high
to mark the last word of the packet presented on the
RDAT[31:0] bus. When REOP is high, RMOD[1:0] specifies if
the last word has 1, 2, 3, or 4 valid bytes of data.
REOP is only used for POS-PHY operation and is updated on
the rising edge of RFCLK.
The POS-PHY receive modulo (RMOD[1:0]) bus indicates
the size of the current word when configured for packet mode.
During a packet transfer, every word on RDAT[31:0] must
contain four valid bytes of packet data except at the end of the
packet where the word is composed of 1, 2, 3, or 4 valid
bytes. The number of valid bytes in this last word is specified
by RMOD[1:0].
RMOD[1:0] is considered valid only when RVAL is asserted.
RMOD[1:0] is only used for POS-PHY operation and is
updated on the rising edge of RFCLK.
RMOD[1:0] = “00”
RMOD[1:0] = “01”
RMOD[1:0] = “10”
RMOD[1:0] = “11”
S/UNI-2488 Telecom Standard Product Datasheet
RDAT[31:0] valid
RDAT[31:8] valid
RDAT[31:16] valid
RDAT[31:24] valid
Released
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