Altera PCI Compiler User Manual
Page 92

3–18
User Guide Version 11.1
Altera Corporation
PCI Compiler
October 2011
PCI Bus Signals
l_adro[63..0]
Output
–
Local address output. The l_adro[63..0] bus is driven by the PCI
MegaCore functions during target transactions. The pci_mt32 and
pci_t32 functions only implement l_adro[31..0]. During dual address
transactions in the pci_mt64 and pci_t64 MegaCore functions, the
l_adro[63..32] bus is driven with a valid address. DAC is indicated by
the assertion of lt_tsr[11]. For more information on the local target
status signals, refer to
The falling edge of lt_framen indicates a valid l_adro[63..0]. The PCI
address is held at the local side as long as possible and should be
assumed invalid at the end of the target transaction on the PCI bus.
The end of the target transaction is indicated by lt_tsr[8] (targ_access)
being deasserted.
l_dato[63..0]
Output
–
Local data output. The
l_dato[63..0]
bus is driven active during
PCI bus-initiated target write transactions or local side-initiated master
read transactions. The functionality of this bus changes depending on
the function you are using and the transaction being considered. The
pci_mt32
and
pci_t32
functions implement only
l_dato[31..0]
. The operation in the
pci_mt64
and
pci_t64
MegaCore functions is dependent on the type of transaction being
considered. During 64-bit target write transactions and master read
transactions, the data is transferred on the entire
l_dato[63..0]
bus. During 32-bit master read transactions, the data is only
transferred on
l_dato[31..0]
. During 32-bit target write
transactions, the data is also only transferred on
l_dato[31..0]
;
however, depending on the transaction address, the
pci_mt64
or
pci_t64
MegaCore function either asserts
l_ldat_ackn
or
l_hdat_ackn
to indicate whether the address for the current data
word is a
QWORD
boundary (
ad[2..0] = B"000"
) or not.
l_beno[7..0]
Output
–
Local byte enable output. The
l_beno[7..0]
bus is driven by the
PCI function during target transactions. This bus holds the byte enable
value during data transfers. The functionality of this bus is different
depending on the function being used and the transaction being
considered. The
pci_mt32
and
pci_t32
functions implement only
l_beno[3..0]
. The operation in the
pci_mt64
and
pci_t64
MegaCore functions is dependent on the type of transaction being
considered. During 64-bit target write transactions, the byte enables
are transferred on the entire
l_beno[7..0]
bus. During 32-bit
target write transactions, the byte enables are transferred on the
l_beno[3..0]
bus and, depending on the transaction address, the
pci_mt64
or
pci_t64
MegaCore function either asserts
l_ldat_ackn
or
l_hdat_ackn
to indicate whether the address
for the current byte enables is at a
QWORD
boundary (
ad[2..0] =
B"000"
) or not.
Table 3–6. PCI Local Address, Data, Command & Byte Enable Signals (Part 2 of 3)
Name
Type
Polarity
Description