Compaq Deskpro 4000 - 4.4 ISA BUS OVERVIEW

Technical Reference Guide
Compaq Deskpro 4000 and 6000 Personal Computers
featuring the Pentium II Processor
First Edition–- October 1997
4-13
4.4 ISA BUS OVERVIEW
NOTE:
This section describes the ISA bus in general and highlights bus
implementation in this particular system. For detailed information regarding ISA bus
operation, refer to the Compaq Extended Industry Standard Architecture (EISA)
Technical Reference Guide.
The industry standard architecture (ISA) bus provides an 8-/16-bit path for standard I/O
peripherals as well as for optional devices that can be installed in the ISA expansion slots. Figure
4-5 shows the key functions and devices that reside on the ISA bus.
Figure 4–6.
ISA Bus Block Diagram
Both desktop and minitower systems provide three ISA connectors for accommodating ISA
expansion cards.
8-/16-Bit ISA Bus
BIOS ROM
and Buffers
ISA Connectors (3)
PCI/ISA
Bridge Function
PCI Bus
Audio
Controller
PC 87307B I/O Controller
Diskette
I/F
Keyboard/
Mouse I/F
Serial
I/F
(
2
)
Parallel
I/F
IrDA
I/F
System
Management
Controller