PM7367 datasheet(304/323 Pages) PMC

304 / 323 page

PM7367 FREEDM-32P32

DATA SHEET

PMC-1991499

ISSUE 2

FRAME ENGINE AND DATA LINK MANAGER

PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMER’S INTERNAL USE

290

Figure 29 – PCI Write Cycle

PCICLK

FRAMEB

AD[31:0]

C/BEB[3:0]

IRDYB

TRDYB

DEVSELB

Address Data 1

Data 2

Data 3

Byte En Byte En

Byte Enable

Bus Cmd

The PCI Target Disconnect (Figure 30) illustrates the case when the target wants

to prematurely terminate the current cycle. Note, when the FREEDM-32P32 is

the target, it never prematurely terminates the current cycle.

A target can terminate the current cycle by asserting the STOPB signal to the

initiator. Whether data is transferred or not depends on the state of the ready

signals at the time that the target disconnects. If the FREEDM-32P32 is the

initiator and the target terminates the current access, the FREEDM-32P32 will

retry the access after two PCI bus cycles.

During clock 1, an access is in progress.

During clock 2, the target indicates that it wishes to disconnect by asserting

STOPB. Data may be transferred depending on the state of the ready lines.

During clock 3, the initiator negates FRAMEB to signal the end of the cycle.

During clock 4, the target negates STOPB and DEVSELB in response to the

FRAMEB signal being negated.

PM7367 Datasheet(PDF) 304 Page - PMC-Sierra, Inc