UPD98405 NEC, UPD98405 Datasheet - Page 17

• Manufacturer Part Number: UPD98405
• Description: 155M ATM INTEGRATED SAR CONTROLLER
• Manufacturer: NEC

<2> PCI bus 64-bit expansion interface signals
AD63-AD32
PCBE7_B
PCBE6_B
PCBE5_B
PCBE4_B
PAR64
REQ64_B
ACK64_B
Pin Name
Open AD63 through AD32, PCBE7_B through PCBE4_B, and PAR64 when using the 32-bit PCI bus interface.
73-75, 79, 80,
100-103,
106-109,
112-115
Pin No.
69-71,
82-85,
88-91,
94-97,
116
63
64
65
66
60
59
Sustained
3-state
3-state
3-state
3-state
3-state
I/O
I/O
I/O
I/O
I/O
I/O
I/O Level
Data Sheet S12689EJ2V0DS00
PCI
PCI
PCI
PCI
CPI
Address/data.
AD63 through AD32 constitutes a 32-bit multiplexed
address/data bus that extends the PCI bus to 64 bits. This
address/data bus transfers the high-order 32 bits of a 64-bit
address in the address phase. It outputs the high-order 32 bits
of 64-bit data in the data phase when both REQ64_B and
ACK64_B are asserted.
Bus command/byte enable.
These signals define a “bus command” (bus transaction that
occurs) in the address phase. In the data phase, they indicate
which byte lane holds valid data. The PCBE7_B pin
corresponds to AD63 through AD56, and PCBE4_B pin
corresponds to AD39 through AD32.
Parity 64.
This signal indicates an even parity on AD63 through AD32 and
PCBE7_B through PCBE4_B pins, including the PAR64 signal.
When the PD98405 is operating as a master, the PAR signal
becomes active in the address and write data phases. When
the PD98405 is operating as a target, it becomes active in the
read data phase.
Request 64.
This signal indicates the start and period of a 64-bit bus
transaction. When the PD98405 is operating as a master, it
asserts REQ64_B active to request 64-bit data transfer.
REQ64_B is the same as FRAME_B in timing.
Acknowledge 64.
When the PD98405 is operating as a target, it makes this
signal low after the REQ64_B signal has been asserted active
and the PD98405 has recognized an address. When the
check whether the target device has acknowledged 64-bit
transfer. ACK64_B is the same as DEVSEL_B in timing.
PD98405 is operating as a master, it samples this signal to
Function
PD98405
17