System I/O; System Bios - Compaq Deskpro 2000 Maintenance & Service Manual

1.3.8

System I/O

The onboard I/O controller integrates the functions for the serial and parallel ports, diskette drives,
the keyboard and mouse. This component provides support for the following:
Multimode bidirectional parallel port
Standard mode: Centronics-compatible operation
High-speed mode with support for an enhanced capabilities port (ECP) and enhanced parallel
port (EPP)
One RS-232C compatible 9-pin serial port
Integrated real-time clock
242-byte, battery-backed CMOS RAM
Integrated 8042-compatible keyboard controller
Industry-standard diskette drive controller that supports 360-kilobyte and 1.2-megabyte
5.25-inch drives
1.3.9

System BIOS

The system BIOS provides ISA and PCI compatibility. Contained in a flash memory device on the
system board, the BIOS provides both the Power-On Self-Test (POST) and PCI and EIDE auto-
configuration utilities.
The system BIOS is always "shadowed." Shadowing allows any BIOS routines to be executed from
fast 64-bit onboard DRAM instead of from the slower 8-bit flash device.
PCI Auto-Configuration
The PCI auto-configuration utility works in conjunction with the Setup program to support using PCI
expansion boards in the system. When you turn on the computer power after installing a PCI board,
the BIOS automatically configures interrupts, I/O space, and PCI devices. If problems arise or you
wish to reconfigure the device, refer to Chapter 2, "Compaq Utilities," which explains how to use the
Setup program. The PCI auto-configuration program complies with version 2.1 of the PCI BIOS
specification.
IDE/EIDE Auto-Configuration
If you install an IDE/EIDE drive into the computer, the IDE/EIDE auto-configuration utility
automatically detects and configures the drive for operation in the computer. This utility eliminates
the need to run the Setup program after you install an IDE/EIDE drive.
ISA Plug and Play Capability
ISA Plug and Play capability provides auto-configuration of Plug and Play ISA boards and resource
management for legacy (non–Plug and Play) ISA boards when used with Computer Setup or a Plug
and Play–compatible operating system like Microsoft's Windows 95.
1-8 Product Description