PMC-Sierra, Inc.

S/UNI-QUAD

DATASHEET

PM5349 S/UNI-QUAD

PMC-971239

ISSUE 6

SATURN USER NETWORK INTERFACE (155-QUAD)

 

 

 

During multi-PHY operation, several PHY layer devices share the TCA signal. As a result, this signals must be tri-stated in all PHY devices which have not been selected for polling by the ATM Layer. The value of TADR[4:0] selects the PHY being polled for the TCA signal, and all devices not corresponding to this address must tri-state its TCA output. This multi-PHY operation is directly supported by the S/UNI-QUAD.

Figure 23: Multi-PHY Polling and Addressing Receive Cell Interface

RFCLK

RCA

 

 

CA(A)

 

 

CA(B)

 

 

CA(C)

 

 

 

 

X

 

CA(B)

 

 

CA(D)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RENB

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RADR[4:0] A

1Fh

B

 

1Fh

C

 

1Fh

X

 

 

 

B

 

1Fh D

1Fh

 

E

RSOC

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RDAT[15:0] W (n-7)

W (n-6)

W (n-5)

W (n-4)

W (n-3)

W (n-2) W (n-1)

W (n)

 

 

 

 

 

 

 

 

W 1

W 2

W 3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RPRTY

Figure 67 shows an example of the multi-PHY polling and selection sequence supported by the S/UNI-QUAD. "A", "B", "C", "D", and "E" represent any arbitrary address values which may be occupied by the S/UNI-QUAD. The ATM Layer device is not restricted in its polling order. The PHY associated with address "A" indicates it does not have a cell available, but PHY "B" indicates that it does. As a result, the ATM Layer places address "B" on RADR[4:0] the cycle before RENB is asserted to select PHY "B" as the next cell source. In this example, PHY "C"s status is ignored. The ATM Layer device is not constrained to select the latest PHY polled. As soon as the cell transfer is started, the polling process may be restarted.

During multi-PHY operation, several PHY layer devices share the RDAT[15:0], RSOC, RPRTY, and RCA signals. As a result, these signals must be tri-stated in all PHY devices which have not been selected for reading or polling by the ATM

Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use

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PMC-Sierra PM5349 manual Multi-PHY Polling and Addressing Receive Cell Interface