HP VECTRA VL 6/XXX 6 Manual

Technical Reference Manual

Hardware and BIOS

HP Vectra VL

6/xxx Series 6 PC

Notice

The information contained in this document is subject to change without notice.

Hewlett-Packard makes no warranty of any kind with regard to this material, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose.

Hewlett-Packard shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance, or use of this material.

Hewlett-Packard assumes no responsibility for the use or reliability of its software on equipment that is not furnished by Hewlett-Packard.

This document contains proprietary information that is protected by copyright. All rights are reserved. No part of this document may be photocopied, reproduced, or translated to another language without the prior written consent of Hewlett-Packard Company.

AdobeTM is a trademark of Adobe Systems Incorporated which may be registered in certain jurisdictions.

Microsoft®, Windows® and MS-DOS® are U.S. registered trademarks of Microsoft Corporation.

Pentium® is a U.S. registered trademark of Intel Corporation.

Hewlett-Packard France

Commercial Desktop Computing Division

38053 Grenoble Cedex 9

France

ã 1997 Hewlett-Packard Company

Preface

This manual is a technical reference and BIOS document for engineers and technicians providing system level support. It is assumed that the reader possesses a detailed understanding of AT-compatible microprocessor functions and digital addressing techniques.

Technical information that is readily available from other sources, such as manufacturer’s proprietary publications, has not been reproduced.

This manual contains summary information only. For additional reference material, refer to the bibliography, on the next page.

Conventions

The following conventions are used throughout this manual to identify specific numeric elements:

Hexadecimal numbers are identified by a lower case h. For example, 0FFFFFFFh or 32F5h

Binary numbers and bit patterns are identified by a lower case b. For example, 1101b or 10011011b

iii

Bibliography

HP Vectra VL 6/xxx Series 6 User’s Guide manual (D5040-90001).

HP Vectra VL 6/xxx MT Series 6 User’s Guide manual (D5050-90001).

HP Vectra VL 6/xxx Series 6 Familiarization Guide (D5040-90901).

HP Network Administrator’s Guide (online).

HP Vectra Accessories Service Handbook - 7th edition

(5965-4074).

HP Vectra PC Service Handbook (Volume 1) - 12th edition

(to be announced).

HP Support Assistant CD-ROM (by subscription).

The following Intel® publications provide more detailed information:

Pentium Pro Family Developer’s Manual, Volume 1: Specifications,

Intel, 1996, ISBN 1-55512-259-0

Pentium Pro Family Developer’s Manual, Volume 2: Programmer’s reference manual, Intel, 1996, ISBN 1-55512-260-4

Pentium Pro Family Developer’s Manual, Volume 3: Operating System Writer’s Manual, Intel, 1996, ISBN 1-55512-261-2

iv

Contents

Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii Conventions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii Bibliography. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv

1 System Overview

Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Minitower Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Specifications and Characteristic Data . . . . . . . . . . . . . . . . . . . . . . . 12

Physical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Environmental Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Electrical Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Where to Find the Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

2 System Board

System Board and Backplane Boards . . . . . . . . . . . . . . . . . . . . . . . . 18

Architectural View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Chip-Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

The PMC, PL/PCI Bridge Chip (82441 FX) . . . . . . . . . . . . . . . . . . . . . . . 21 The DBX, Data Bus Accelerator Chip (82442 FX) . . . . . . . . . . . . . . . . . 22 The PIIX3, PCI/ISA Bridge Chip (82371SB) . . . . . . . . . . . . . . . . . . . . . . 23 The SIO, Super I/O Controller (NS 87308) . . . . . . . . . . . . . . . . . . . . . . . 24

Devices on the Processor-Local Bus . . . . . . . . . . . . . . . . . . . . . . . . . 26

Intel Pentium II Microprocessor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Cache Memory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

DRAFT

v

Contents

Main Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	28
Devices on the PCI Bus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	29
Integrated Drive Electronics (IDE). . . . . . . . . . . . . . . . . . . . . . . . . . . . .	29
Universal Serial Bus (USB) Controller . . . . . . . . . . . . . . . . . . . . . . . . . .	30
Devices on the ISA Bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	31
Super I/O Controller. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	31
Little Ben . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	34
Other PCI and ISA Accessory Devices Under Plug and Play . . . . . . . . .	35
3 Interface Devices and Mass-Storage Drives
Cirrus 5446 Graphics Controller Chip. . . . . . . . . . . . . . . . . . . . . . . . .	38
Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	38
Video Memory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	39
Video Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	39
Available Video Resolutions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	42
Matrox MGA Millennium II Graphics Controller Board . . . . . . . . . .	44
Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	45
Video Memory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	45
Available Video Resolutions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	45
Video BIOS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	47
Audio Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	48
Mass-Storage Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	50
Hard Disk Drives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	50
Flexible Disk Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	50
CD-ROM Drives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	50
Connectors and Sockets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	51

vi

DRAFT

Contents

4 Summary of the HP/Phoenix BIOS

HP/Phoenix BIOS Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

Setup Program. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Main Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Configuration Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Security Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Power Menu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Power Saving and Ergonometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

Power-On from Space-Bar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Soft Power Down. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

BIOS Addresses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

System Memory Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 Product Identification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 HP I/O Port Map (I/O Addresses Used by the System). . . . . . . . . . . . . . 65

5 Power-On Self-Test and Error Messages

Order in Which the Tests are Performed . . . . . . . . . . . . . . . . . . . . . . 72 Error Message Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 Beep Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 Lights on the Status Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

DRAFT

vii

Contents

viii

DRAFT

1

System Overview

This manual describes the HP Vectra VL 6/xxx Series 6 PC, and provides detailed system specifications.

This chapter introduces the external features, and lists the specifications and characteristic data of the system. It also summarizes the documentation which is available.

9

1 System Overview

Package

Package

Front view

Front view with cover removed

activity light

status light

(Multimedia models only)

Hard disk drive 24 CD-ROM drive Flexible disk drive

System board switches

Video memory

Processor

VRM

Main memory

Retaining brackets

Rear view

Security lock hole

Display Keyboard USB Mouse	Parallel	Serial A	Serial B

(All icons shown here are for information, and do not necessarily appear on the PC).

10

1 System Overview

Package

Front view with cover removed

Minitower Package

System board switches

Processor

VRM

Video memory

Main memory

Rear view

Serial B

Serial A

Parallel

Mouse

USB

Keyboard

Voltage selection switch

Display

(All icons shown here are for information, and do not necessarily appear on the PC).

11

1 System Overview

Specifications and Characteristic Data

Specifications and Characteristic Data

Physical Characteristics

System Processing Unit

	Desktop	Minitower
Weight	9 kg (20 lbs)	15 kg (33 lbs)
Dimensions	44.6 cm (D) by 43.5 cm (W) by 13.2 cm (H)	44 cm (D) by 19.2 cm (W) by 43.8 cm (H)
	17.5 inches by 17.1 inches by 5.2 inches	17.3 inches by 7.6 inches by 17.2 inches
Footprint	0.194 m2 (2.08 sq ft)	0.085 m2 (0.91 sq ft)

	Keyboard
Flat	464 mm (W) by 178 mm (D) by 33 mm (H) (18.3 inches by 7 inches by 1.3 inches)
Standing	464 mm (W) by 178 mm (D) by 51 mm (H) (18.3 inches by 7 inches by 2 inches)

Environmental Specification

System Processing Unit with a Hard Disk

Acoustic noise emission (operating)	LwA < 40 dB	LpA < 35 dB
Acoustic noise emission (operating	LwA < 41 dB	LpA < 35 dB
with hard disk drive access)
Acoustic noise emission (operating	LwA < 43 dB	LpA < 38 dB
with flexible disk drive access)
Operating temperature	+10°C to +40°C	(+50°F to 104° F)
Recommended operating temperature	+15°C to +40°C	(+59°F to +104°F)
Storage temperature	-40°C to +70°C	(-40°F to +158°F)
Over temperature shutdown	+50°C	(+122°F)
Operating humidity	15% to 80% (relative)
Storage humidity	8% to 80% (relative), non-condensing at 40°C (104°F)
Operating altitude	3100 m max	(10000 ft max)
Storage altitude	4600 m max	(15000 ft max)

Operating temperature and humidity ranges may vary depending upon the mass storage devices installed. High humidity levels can cause improper operation of disk drives. Low humidity levels can aggravate static electricity problems and cause excessive wear of the disk surface.

12

1 System Overview

Specifications and Characteristic Data

Electrical Specification

For the desktop models:

		Limit for the Power				Limit per PCI	Limit per ISA
	Parameter				Notes	Accessory	Accessory
		Supply
						Slot	Slot
	Input voltage	100-127		200-240
		Vac		Vac	Auto-ranging
	Input voltage range	90-264 Vac
	Input current (max)		3 A
	Input power (max)	150 W
	Input power (typical1)	<63 W		<65 W	Fully-on mode (with input/output)
		<31 W		<34 W	Fully-on mode (without input/output)
		<30 W		<30 W	Standby mode
		<24 W		<24 W	Suspend mode
		<1.2 W		<2.8 W	Off (but plugged in)
	Input frequency	45 Hz to 66 Hz
	Available power	120 W (continuous)				25 W (max)	7 W (max)
	Max current at +5 V	13.5 A				4.5 A	4.5 A
	Max current at +3.3 V		6 A			—	—
	Max current at -5 V	0.1 A				—	0.1 A
	Max current at +12 V	4.5 A				0.5 A	1.5 A
	Max current at -12 V	0.3 A				0.1 A	0.3 A

1.Dependant on operating system and PC configuration

13

1 System Overview

Specifications and Characteristic Data

For the minitower models:

		Limit for the Power			Limit per PCI	Limit per ISA
	Parameter			Notes	Accessory	Accessory
		Supply
					Slot	Slot
	Input voltage	100-127	200-240
		Vac	Vac	Switch selectable
	Input voltage range	90-140	180-264
		Vac	Vac
	Input current (max)	5 A	3 A
	Input power (max)	200 W
	Input power (typical1)	<59 W	<58 W	Fully-on mode (with input/output)
		<35 W	<35 W	Fully-on mode (without input/output)
		<30 W	<30 W	Standby mode
		<24 W	<24 W	Suspend mode
		<1.3 W	<1.3 W	Off (but plugged in)
	Input frequency	45 Hz to 66 Hz
	Available power	160 W (continuous)			25 W (max)	7 W (max)
	Max current at +5 V	20 A			4.5 A	4.5 A
	Max current at +3.3 V	12 A			—	—
	Max current at -5 V	0.2 A			—	0.1 A
	Max current at +12 V	4.4 A			1.5 A	0.5 A
	Max current at -12 V	0.5 A			0.1 A	0.3 A
	Max current at +5 Vst	0.05 A			—	—

1.Dependant on operating system and PC configuration

When the computer is turned off, but left plugged in at the mains, the power consumption falls below 5 watts, but is not zero. If the computer is completely unplugged from the mains, the real time clock continues to operate from the charge stored in the battery. If the computer is left plugged in, but not turned on, it continues to supply power to the real time clock, and also keeps the battery recharged. The life-time of rechargeable batteries is considerably extended by keeping them in a fully charged state.

The battery can be recharged by plugging the computer back in for at least an hour. It is not necessary to start the computer.

14

1 System Overview

Documentation

Documentation

The table below summarizes the availability of documentation that is appropriate to the HP Vectra VL 6/xxx Series 6 PCs. Only selected publications are available on paper. Most are available as viewable files (which can also be printed) from the HP division support servers, and on the HP Support Assistant CD-ROM.

	Division Support Server	Support Assistant CD-ROM	Paper-based
HP Vectra VL 6/xxx Series 6	PDF file	PDF file	DT: D5040A
User’s Guide			MT: D5050A
HP Vectra VL 6/xxx Series 6	PDF file	PDF file	D5040-90901
Familiarization Guide
HP Vectra VL 6/xxx Series 6	PDF file	PDF file	no
Technical Reference Manual
HP Vectra PC Service	PDF file	PDF file	To be announced
Handbook (Vol 1, 12th Edition)
HP Vectra Accessory Service	PDF file	PDF file	5965-4074
Handbook (7th Edition)

Each PDF file (portable document format) can be viewed on the screen by opening the file with Acrobat Reader. To print the document, press Ctrl+P whilst you have the document on the screen. You can use the page-up, pagedown, goto page, search string functions to read the document on the screen. (Note, though, that for some documents, there is difference between the page number that is printed on the page, and the page number that Acrobat Reader indicates, because of the presence of the front matter pages).

15

1 System Overview

Documentation

Where to Find the Information

The following table summarizes the availability of information within the

HP Vectra VL 6/xxx Series 6 PC documentation set.

					Familiarization	Service	Technical
		User Guide		User Online			Reference
					Guide	Handbook
							Manual
				Introducing the computer
Product features	Key features			Exploring	New features	Exploded view	Key features
						Parts list
Product model numbers						Product range
						CPL dates
				Using the computer
Connecting cables and	Keyboard, mouse, display,
turning on	network, printer, power
Finding on-line	Finding READ.MEs and on-
information	line documentation
Environmental				Working in			System overview
				comfort
Formal documents	Software license agreement			S/w license
	Warranty information			agreement
				Upgrading the computer
Opening the computer	Full details
Supported accessories	Some part number details					Full PN details
Replacing accessories	How to install				New procedures
Configuring devices				Configuring			Problem fixes
				peripherals
Fields and their options							Key fields
within Setup
				Repairing the computer
Troubleshooting	Basic				New symptoms	Service notes	Advanced
Technical information	Basic			Detailed			Advanced
System board	Jumpers, switches and				Jumpers, switches	Jumpers,	Jumpers, switches
	connectors				and connectors	switches and	and connectors
					How to replace	connectors	Chip-set details
BIOS	Basic details				Upgrading		Technical details
							Memory maps
Power-On Self-Test	Key error codes and						Order of tests
routines (POST)	suggestions for corrective						Complete list
	action

16

2

System Board

The next chapter describes the graphics, disk and audio devices which are supplied with the computer.

This chapter describes the components of the system board, taking in turn the components of the Processor-Local Bus, the Peripheral Component Interconnect (PCI) bus and the Industry Standard Architecture (ISA) bus.

17

2 System Board

System Board and Backplane Boards

System Board and Backplane Boards

Most desktop and minitower models are supplied with a Matrox graphics controller on a PCI board, and do not have the integrated graphics controller loaded on the system board.

Status Panel

						A				Voltage Regulator Module
	Power Connector					A
						B		Not Used
						B
						C			V Connector
						C
				Memory Slots
									3.3
342	Flexible Disk Connector	CD-ROM Connector	Hard Disk Connector							Processor Slot
mm
									Connector
		(Items shown in grey are							External Speaker	System Board Switches	External Battery Connector
		present only on models with					Internal Speaker
		integrated graphics controller)
			Graphics			Video Memory
			Controller					Start
			Chip
		VESA Connector						External
		Display	Kbd	2	Mou	Parallel Port	Serial Port A			Serial Port B
				USB

210 mm

18

2 System Board

System Board and Backplane Boards

Desktop (front view)

2 PCI slot (shown in white)

2 ISA/PCI combination slot (shown in light grey)

1 system board slot (shown in dark grey)

Desktop (rear view)

1 ISA slot (shown in grey)

Minitower (top view)

2 ISA slot (shown in grey)

2 PCI slot (shown in white)

2 ISA/PCI combination slot (shown in light grey)

1 system board slot (shown in dark grey)

PCI Slot #4 (J12)

PCI Slot #3 (J5)

PCI Slot #2 (J11)

PCI Slot #1 (J6)

PCI Slot #4 (J12)

PCI Slot #3 (J5)

PCI Slot #2 (J11)

PCI Slot #1 (J6)

19

2 System Board

Architectural View

Pentium II

Processor

L2 cache memory

Architectural View

Processor-Local Bus	PCI Bus	ISA Bus
(64 bit, 60/66 MHz)	(32 bit, 30/33 MHz)	(16 bit, 7.5/8.25 MHz)

82441 FX

82371 SB

PL/PCI Bridge (PMC)

PCI/ISA Bridge (PIIX3)

PL bus

PCI bus

Interrupt

DMA

interface

interface

controller

controller

DBX

Memory

PCI bus

ISA bus

interface

controller

interface

interface

2 USB

2 IDE

controller

controller

Main

memory

Hard

disk

82442 FX

Data bus accelerator (DBX)

Serial

Little Ben

PMC

DRAM

EEPROM

(HP ASIC)

interface

interface

PL bus

PCI bus

interface

interface

PC87308

Super I/O

Keyboard

Mouse

controller

controller

CL5446 or Millennium II

Graphics controller

Parallel

ISA bus

controller

interface

2 serial

FDD

controller

Controller

System Flexible

ROM disk

20

2 System Board

Chip-Set

Chip-Set

The chip-set comprises four chips. These interface between the three main buses (the Processor-Local bus, the PCI bus and the ISA bus).

•The PMC chip (82441FX) is a combined PL/PCI bridge and main memory controller.

•The DBX chip (82442FX) is the data bus accelerator, implementing the datapath between the processor local bus and main memory.

•The PIIX3 chip (82371SB) is a combined PCI/ISA bridge and IDE controller and USB controller.

•The Super I/O chip (37C932) is a combined serial interface and parallel interface and keyboard controller and mouse controller and flexible disk drive controller.

	The PMC, PL/PCI Bridge Chip (82441 FX)
	This forms the bridge between the Processor Local Bus (PL Bus) and the
	PCI Bus.
PL Bus Interface	The PMC chip monitors each cycle that is initiated by the processor, and
	forwards those to the PCI bus that are not targeted at the local memory. It
	translates PL bus cycles into PCI bus cycles.
	The chip supports the SMM mode of the Pentium processor, the CPU stop
	clock hardware function, and the keyboard lock function. These are used by
	the LittleBen chip, as described on page 34.
PCI Bus Interface	Sequential PL-to-PCI memory write cycles are translated into PCI zero wait
	state burst cycles. The maximum PCI burst transfer can be between
	256 bytes and 4 KB. The chip supports advanced snooping for PCI master
	bursting, and provides a pre-fetch mechanism dedicated for IDE read.
	The PCI arbiter supports PCI bus arbitration for up to four masters using a
	rotating priority mechanism. Its hidden arbitration scheme minimizes
	arbitration overhead.

21

2 System Board

Chip-Set

Main Memory Controller	The main memory controller supports up to 512 MB of dynamic random
	access memory (DRAM), arranged in banks of any mixture of memory
	capacities, provided that each bank contains a pair of identical single
	interline memory modules (SIMMs). With the 32 MB module from HP, the
	three banks on these PCs gives a total capacity of 192 MB. With a 64 MB
	module from HP, it will give a total capacity of 384 MB.
DBX Interface	The DBX chip, described next, is controlled by the PMC chip.
	The DBX, Data Bus Accelerator Chip (82442 FX)
PMC Interface	The DBX chip implements a 64-bit data path (not interleaved) between the
	Processor-Local bus and main memory modules.
PL Bus Interface	This unit takes the data from the Processor Local bus that is to be written to
	the memory, and takes the data out to the Processor Local bus that has been
	read from the memory.
Data Path	Storage elements are provided for bidirectional data buffering among the
	64-bit PL data bus, the 64/32-bit memory data bus, and the 32-bit PCI
	address/data bus.
	There are three FIFO (first-in first-out) queues, and one read buffer for the
	paths between the PL, PCI, and Memory buses. This buffering is used,
	partly, to smooth the differences in bandwidths between the three buses,
	thereby improving the overall system performance. During bus operations
	between the PL, PCI and Memory buses, the chip receives control signals
	from the PMC, performs functions such as data latching, data forwarding to
	the destination bus, and data assemble and disassemble.
	Whilst accesses to the local memory are in progress, whether it be from the
	PL or PCI bus, the PMC maintains control of the secondary cache, DRAMs,
	and the datapath.
DRAM Interface	In the case of 66 MHz PL bus operation, memory accesses have a timing
	pattern of 5-2-2-2 for a page-hit. This degrades to 8-2-2-2 for a row-miss,
	and to 11-2-2-2 for a page-miss. When the banks have been filled in an
	arbitrary order, back-to-back burst reads keep to the 5-2-2-2,5-2-2-2 timing

22

2 System Board

Chip-Set

	pattern. When the banks have been filled contiguously (bank A, then bank
	B, then bank C), back-to-back burst reads are improved to a 5-2-2-2,3-2-2-2
	timing pattern.
	The controller supports relocation of system management memory. It
	supports a read cycle power saving mode, and a CAS before RAS Intelligent
	Refresh mode of operation, with a CAS# driving current that is
	programmable.
	The controller is fully configurable for the characteristics of the shadow
	RAM (640 KB to 1 MB). It supports concurrent write back.
	The PIIX3, PCI/ISA Bridge Chip (82371SB)
	This chip is encapsulated in a 208 pin plastic quad flat pack (PQFP)
	package.
PCI Bus Interface	This part of the chip is responsible for transferring data between the PCI bus
	and the ISA expansion bus. It performs PCI-to-ISA, and ISA-to-PCI bus cycle
	translation. It supports the Plug-and-Play mechanism. Data buffers are
	provided, to isolate the PCI and ISA buses.
ISA Bus Interface	As well as accepting cycles from the PCI bus interface, and translating them
	for the ISA bus, the ISA bus interface also requests the PCI master bridge to
	generate PCI cycles on behalf of a DMA or ISA master. The ISA bus interface
	contains a standard ISA bus controller and data buffering logic. It can
	directly support six ISA slots without external data or address buffering.
IDE Controller	The PCI master/slave IDE controller, supporting four devices, two on each of
	two channels, is described on page 29.
USB Controller	The PCI USB controller, supporting two connectors, is described on page 30.
DMA Controller	The seven channel DMA controller incorporates the functionality of two
	82C37 DMA controllers. Channels 0 to 3 are for 8-bit DMA devices, while
	channels 5 to 7 are for 16-bit devices (see page 67). The channels can be
	programmed for any of the four transfer modes: the three active modes
	(single, demand, block), can perform three different types of transfer: read,
	write and verify. The address generation circuitry supports a 24-bit address
	for DMA devices.

23

2 System Board

Chip-Set

Interrupt Controller The sixteen channel interrupt controller incorporates the functionality of two 82C59 interrupt controllers. The two controllers are cascaded, giving 14 external and two internal interrupt sources (see page 67).

Counter / Timer	The chip contains a three-channel 82C54 counter/timer. The counters use a
	division of the 14.318 MHz OSC input as the clock source.

The SIO, Super I/O Controller (NS 87308)

The Super I/O chip (NS 87308) provides the control for two FDC devices, two serial ports and one bidirectional multi-mode parallel port.

Function	Logical device number
Flexible disk controller	0 ??
Parallel port controller	3 ??
UART1 controller	4 ??
UART2 controller	5 ??
RTC	6 ??
Keyboard controller	7 ??
Mouse controller	7 ??
General purpose I/O (GPIO)	8 ??

Serial / parallel communications ports

The two 9-pin serial ports (whose pin layouts are depicted on page 55) support RS-232-C and are buffered by 16550 UARTs, with 16 Byte FIFOs. They can be programmed as COM1, COM2, COM3, COM4, or disabled.

The 25-pin parallel port (also depicted on page 55) is Centronics compatible, supporting IEEE 1284. It can be programmed as LPT1, LPT2, or disabled. It can operate in the following four modes:

Standard mode (PC/XT, PC/AT, and PS/2 compatible).

Bidirectional mode (PC/XT, PC/AT, and PS/2 compatible).

Enhanced mode (enhanced parallel port, EPP, compatible).

High speed mode (MS/HP extended capabilities port, ECP, compatible).

24