SB82371 Intel Corporation, SB82371 Datasheet - Page 92

• Manufacturer Part Number: SB82371
• Description: 82371FB (PIIX) AND 82371SB (PIIX3) PCI ISA IDE XCELERATOR
• Manufacturer: Intel Corporation

82371FB (PIIX) AND 82371SB (PIIX3)
3.3.
The PIIX/PIIX3 incorporates a fully ISA Bus compatible master and slave interface. The PIIX/PIIX3 directly
drives five ISA slots without external data buffers. External transceivers are used on the SA[19:8] and SBHE#
signals to permit these signals to be used with the IDE interface (Figure 1). The ISA interface also provides
byte swap logic, I/O recovery support, wait state generation, and SYSCLK generation.
The ISA interface supports the following types of cycles:
92
PCI master-initiated I/O and memory cycles to the ISA Bus
DMA compatible cycles between main memory and ISA I/O and between ISA I/O and ISA memory
Enhanced DMA cycles between PCI memory and ISA I/O (for motherboard devices only)
ISA refresh cycles initiated by either the PIIX/PIIX3 or an external ISA master
ISA master-initiated memory cycles to PCI and ISA master-initiated I/O cycles to the internal PIIX/PIIX3
registers, as shown in ISA-Compatible Register table in the Register Description section.
ISA Interface
PIIX/PIIX3
ISA
Control
Signals
SD[15:0]
LA[23:17]
Figure 1. ISA Interface
SA[7:0]
BIOSCS#,
RTCCS#,
KBCCS#
SOE#,
SDIR
14
ALS245
SA[19:8]
SBHE#
PCS#
DD[15:0]
051908_3.drw
To IDE
Connector
051908