Master mode operation – Altera PCI Compiler User Manual

Page 208

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3–134

User Guide Version 11.1

Altera Corporation

PCI Compiler

October 2011

64-Bit Addressing, Dual Address Cycle (DAC)

Master Mode Operation

A master operation begins when the local-side master interface asserts
the lm_req64n signal to request a 64-bit transaction or the lm_req32n
signal to request a 32-bit transaction. The pci_mt64 function outputs the
reqn

signal to the PCI bus arbiter to request bus ownership. The

pci_mt64

function also outputs the lm_adr_ackn signal to the local

side to acknowledge the request. When the lm_adr_ackn signal is
asserted, the local side provides the PCI address on the l_adi[63..0]
bus, the DAC command on l_cbeni[3..0], and the transaction
command on l_cbeni[7..4]. When the PCI bus arbiter grants the bus
to the pci_mt64 function by asserting gntn, pci_mt64 begins the
transaction with a dual address phase. The pci_mt64 function asserts
the framen signal in the first clock cycle, which is called the first address
phase. During the first address phase, the pci_mt64 function drives the
64-bit transaction address on ad[63..0], the dual address cycle
command on cben[3..0], and the transaction command on
cben[7..4]

. On the following clock cycle, during the second address

phase, the pci_mt64 function drives the upper 32-bit transaction
address on both ad[63..32] and ad[31..0], and the transaction
command on both cben[7..4] and cben[3..0].

64-Bit Address, 64-Bit Data Master Burst Memory Read Transaction

Figure 3–49

shows the waveform for a 64-bit address, 64-bit data master

burst memory read transaction.

Figure 3–49

is exactly the same as

Figure 3–31

, except that

Figure 3–49

has two address phases (as described

in the previous paragraph).

1

All 32-bit addressing transactions described in

“Master Mode

Operation” on page 3–134

are applicable for 64-bit addressing

transactions, except for the differences described in the previous
paragraph.

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