14
1 HP Vectra 500 Series
Principal Components and Features
The PCI/ISA Bridge and IDE Controller (82371FB)
The 82371FB device serves as a bridge between the PCI bus and the ISA
expansion bus, and incorporates a two-channel PCI IDE controller. It
incorporates the logic for a PCI interface, a DMA interface, a DMA controller
that supports fast DMA transfers, data buffers to isolate the PCI and ISA
buses, Timer/Counter logic, and NMI control logic.
The 82371FB PCI/ISA bridge also provides decode for the following
peripheral devices:
•
Flash BIOS
•
Real Time Clock/CMOS Memory
•
Keyboard/Mouse Controller
•
Flexible Disk Controller
•
Two Serial Ports
•
One Parallel Port
•
PCI Accessory Board Slots.
The 82438FX and 82371FB Feature Summary
Function
Features
Data buffer
(for 82438FX and 82371FB together)
❒
Provides a high performance 64-bit data path between the
processor (local) bus and main memory
❒
Provides a 32-bit data path to the PCI bus
❒
Provides a 8-deep x 64-bits wide write buffer for all processor
writes to main memory
❒
Provides a one-level posted write buffer for all processor writes
to PCI bus memory
PCI master / slave interface
(for 82371FB only)
❒
Fully compatible with PCI specification
❒
Supports PCI-to-ISA / ISA-to-PCI bus master cycle translations
❒
Supports programmable memory regions to provide fast
positive decode for PCI master accesses
❒
Implements subtractive decoding for unclaimed PCI cycles
❒
Supports PCI-to-ISA posted memory writes
❒
Translates DMA transfers for PCI slaves
❒
Supports PCI address/data parity generation and checking
