DEC DECstation 316+, DECstation 325c, DECstation 333c, DECstation 320+, DECstation 425c Service Manual

DECstation

+/320+ /325C/333C /425C

316 ServiceGuide

Order Number EK-PC46A-SV-002

Digital Equipment Corporation

First Edition, January 1990, Second Edition, October 1990

The information in this document is subject to change without notice and should not be construed as a commitment by Digital Equipment Corporation. Digital Equipment Corporation assumes no responsibility for any errors that may appear in this document.

The software described in this document is furnished under a license and may be used or copied only in accordance with the terms of such license.

No responsibility is assumed for the use or reliability of software on equipment that is not supplied by Digital Equipment Corporation or its afﬁliated companies.

Restricted Rights: Use, duplication, or disclosure by the U. S. Government is subject to restrictions as set forth in subparagraph (c) ( 1) (ii) of the Rights in Technical Data and Computer Software clause at DFARS 252.227–7013.

Printed in U.S.A.

FCC NOTICE: The equipment described in this manual has been certiﬁed to comply with the limits for a Class B computing device, pursuant to Subpart J of Part 15 of FCC Rules. Only peripherals (computer input/output devices, terminals, printers, etcetera) certiﬁed to comply with the Class B limits may be attached to this computer. Operation with noncertiﬁed peripherals may result in interference to radio and television reception. This equipment generates and uses radio frequency energy and if not installed and used properly, that is, in strict accordance with the manufacturer’s instructions, may cause interference to radio and television reception. It has been type tested and found to comply with the limits for a Class B computing device in accordance with the speciﬁcations in Subpart J of Part 15 of FCC Rules, which are designed to provide reasonable protection against such interference in a residential installation. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

– Reorient the receiving antenna. – Move the computer away from the receiver. – Plug the computer into a different outlet so that computer and receiver are

on different branch circuits.

If necessary, the user should consult the dealer or an experienced radio/television technician for additional suggestions. The user may ﬁnd the following booklet prepared by the Federal Communications Commission helpful: How to Identify and Resolve Radio-TV Interference Problems. This booklet is available from the US Government Printing Ofﬁce, Washington, DC 20402, Stock No. 004–000– 00398–5

The following are trademarks of Digital Equipment Corporation: DEC DIBOL UNIBUS

DEC/CMS EduSystem VAX DEC/MMS IAS VAXcluster DECnet MASSBUS VMS DECsystem–10 PDP VT DECSYSTEM–20 PDT DECUS RSTS DECwriter RSX

MS-DOS is a registered trademark of Microsoft Corporation. Velcro is a trademark of VELCRO USA Inc. IBM and IBM-PC/AT are registered trademarks of International Business

Machines Corporation. INTEL is a trademark of Intel Corporation. Diagnose is a trademark of Teknosis.

This document was prepared and published by Educational Services Development and Publishing, Digital Equipment Corporation.

Contents

About This Manual vii

1 Overview

1.1 Introduction ...................................... 1–1

1.2 DECstation Base System ............................ 1–2

1.3 DECstation Options ................................ 1–3

1.3.1 System Unit Layout .............................. 1–3

1.4 DECstation System Conﬁgurations .................... 1–4

1.4.1 DECstation Main Logic Board ...................... 1–7

1.4.2 DECstation 316+ CPU Board ....................... 1–7

1.4.3 DECstation 325C CPU Board ....................... 1–7

1.4.4 DECstation 333C CPU Board ....................... 1–8

1.4.5 DECstation 320+ CPU Board ....................... 1–8

1.4.6 DECstation 425C CPU Board ....................... 1–8

1.4.7 Power Supply . . . ................................ 1–8

1.4.8 Monitors....................................... 1–8

1.4.9 Video Graphics Array Adapter ...................... 1–11

1.4.10 Enhanced Keyboards ............................. 1–11

1.4.10.1 101-Key Enhanced Keyboard ..................... 1–11

1.4.10.2 LK250 Keyboard .............................. 1–12

1.4.11 Math Coprocessor................................ 1–12

iii

iv Contents

2 Troubleshooting

2.1 Special Tools ..................................... 2–1

2.2 Diagnostics....................................... 2–2

2.3 Normal Power Up . ................................ 2–3

2.4 Troubleshooting Procedures . . ........................ 2–3

2.4.1 Getting Started . ................................ 2–3

2.4.2 No Power ...................................... 2–5

2.4.3 System Does Not Boot ............................ 2–6

2.4.4 System Boots . . . ................................ 2–6

2.5 Error Codes and Messages . . . ........................ 2–7

2.5.1 Power Up Beep Codes ............................ 2–7

2.5.2 Test Messages . . ................................ 2–11

2.6 Troubleshooting by Symptom . ........................ 2–13

2.6.1 System Unit Problems ............................ 2–13

2.6.2 Disk Related Problems ............................ 2–16

2.6.3 Monitor Problems................................ 2–17

2.7 Troubleshooting Problems Occurring During System

Operation ........................................ 2–20

2.8 Using the System Utilities Diskette .................... 2–21

2.8.1 Running the Setup Program ....................... 2–21

3 FRU Replacement

3.1 Introduction ...................................... 3–1

3.1.1 Before Replacing FRUs . . . ........................ 3–5

3.2 Replacing FRUs . . . ................................ 3–6

3.2.1 Keyboard Replacement............................ 3–8

3.2.2 Monitor Replacement............................. 3–8

3.2.3 Mouse Replacement .............................. 3–8

3.2.4 System Cover Removal ............................ 3–9

3.2.5 Floppy Disk Drive Replacement ..................... 3–10

3.2.5.1 Replacing An Optional Floppy Drive ............... 3–11

3.2.6 Replacing an Optional Hard Disk/Tape Drive . . . ....... 3–12

3.2.7 CPU Board Replacement . . ........................ 3–12

3.2.8 DECstation 325C/ 333C Math Coprocessor Replacement . . 3–12

3.2.9 DECstation 316+/ 320+ Math Coprocessor Replacement . . . 3–14

3.2.10 425C Math Coprocessor Replacement . . ............... 3–16

Contents v

3.2.11 The 0K Memory Adapter . . ........................ 3–18

3.2.11.1 Single-In-Line Memory Module Replacement . . ....... 3–20

3.2.12 Option Board Replacement ........................ 3–22

3.2.13 Power Supply Removal . . . ........................ 3–23

3.2.14 Fan Removal . . . ................................ 3–26

3.2.15 Main Logic Board Replacement ..................... 3–28

3.2.16 Speaker Removal ................................ 3–30

3.2.17 Battery Replacement ............................. 3–30

3.3 Jumper Locations and Conﬁgurations . . . ............... 3–31

A Power Consumption

B Peripheral Interface

Index

Figures

1–1 DECstation Personal Computer ....................... 1–1

1–2 System Unit Layout ................................ 1–4

3–1 Exploded View of DECstation Chassis . . . ............... 3–6

3–2 Exploded View of DECstation Main Logic Board and Options 3–7

3–3 Removing the DECstation System Cover . ............... 3–9

3–4 Replacing the Floppy Disk Drive ...................... 3–11

3–5 DECstation 325C/ 333C CPU Board.................... 3–13

3–6 DECstation 316+/320+ CPU Board ..................... 3–15

3–7 DECstation 320+/425C CPU Board ..................... 3–17

3–8 The 0K Memory Adapter (With no foil backing) ........... 3–18

3–9 The 0K Memory Adapter (With foil backing) ............. 3–19

3–10 SIMM Removal and Replacement ..................... 3–21

3–11 Removing the Rear Bezel ............................ 3–24

3–12 Removing the Power Supply . ........................ 3–25

3–13 Fan Removal and Replacement ....................... 3–27

3–14 Removing the Main Logic Board ...................... 3–29

3–15 CPU Logic Board Jumper Location (425C)............... 3–31

vi Contents

3–16 Rev. C Main Logic Board Jumper Locations (316+/

325C/333C)....................................... 3–34

3–17 Rev. D Main Logic Board Jumper Locations (320+/ 425C) . . . 3–37

Tables

1–1 Base System Conﬁgurations . . ........................ 1–5

1–2 Monitors. ........................................ 1–9

1–3 Math Coprocessors . ................................ 1–12

2–1 Troubleshooting Tools............................... 2–2

2–2 Primary Beep Codes ................................ 2–8

2–3 Secondary Beep Codes .............................. 2–9

2–4 BIOS Error Messages ............................... 2–11

2–5 System Unit Troubleshooting Procedures . ............... 2–13

2–6 Hard Disk and Diskette Drive Troubleshooting Procedures . . 2–16

2–7 Monitor Troubleshooting Procedures ................... 2–17

3–1 DECstation Standard Field Replaceable Units ........... 3–1

3–2 DECstation Optional Field Replaceable Units ............ 3–2

3–3 DECstation 325C/316+ Main Logic Board Jumper Settings for

Rev C Boards ..................................... 3–32

3–4 DECstation 425C/320+ Main Logic Board Jumper Settings for

Rev D Boards ..................................... 3–35

A–1 DECstation Base System Power Consumption ............ A–1

B–1 Parallel I/O Port Connector . . ........................ B–1

B–2 RS-232C Serial Port Connector ....................... B–2

B–3 Keyboard and Mouse Connectors ...................... B–2

B–4 Video Port Connector ............................... B–3

AboutThis Manual

This service guide is designed to help you diagnose and repair the DECstation 316+, DECstation 320+, DECstation 333C, and DECstation 425C personal computers. This guide contains information on servicing the base system only. Speciﬁc information on installing, replacing, and conﬁguring options is covered in the individual option installation guides supplied with those products, and is available to Customer Service personnel in a kit.

Guide Organization

The guide is organized as follows:

• Chapter 1 provides an overview of the DECstation systems.

• Chapter 2 details troubleshooting instructions.

• Chapter 3 contains procedures for removing and replacing

ﬁeld replaceable units.

For information about network troubleshooting, refer to the PCSA Network Troubleshooting Guide. For additional information about PC architecture and the Digital Ethernet Personal Computer Bus Adapter (DEPCA) and DECetherWORKS option boards, refer to the appropriate Service Guides.

Intended Audience

The procedures in this guide are for service technicians trained only by Digital Equipment Corporation.

vii

viii About This Manual

Conventions

This document uses the following conventions:

Convention Meaning

Warning Provides information to prevent Caution Provides information to prevent Note Provides general information you

Ctrl Alt Del

Strike the F1 key What the screen displays as a

personal injury damage to equipment should be aware of

Alt

Ctrl

and

while you

Del

. Control

Press and hold press both

key sequences have special functions.

prompt or an instruction is shown in monospaced type.

Throughout this guide, DECstation refers to the DECstation 316+, the DECstation 320+, the DECstation 325C, the DECstation 333C, and the DECstation 425+. When information applies to a speciﬁc DECstation, the full name is used.

The computer industry recognizes two open architectures as industry standards: The IBM-PC/AT bus structure and the Microsoft disk operating system, MS-DOS. The term industrystandard refers to compatibility with these architectures. Support for MS-DOS requires a deﬁned set of ROM-BIOS (read-only memory basic I/O system services) which the DECstation offers.

Ordering Parts

Customers who maintain their own equipment can order spare parts by either phone or mail, or through any Digital sales ofﬁce.

To order parts by phone, call 1-800-DIGITAL from 8:30 am to 8:00 pm (Eastern Standard Time).

About This Manual ix

To order parts by mail, send a purchase order to:

Digital Equipment Corporation P.O. Box CS2008 Nashua NH 03061

Related Documentation

The following related documents are available as supplements to the information provided in this guide.

Document Part Number

DECstation 316+ User’s Guide ER-PC461-UG DECstation 320 DECstation 325 DECstation 333 DECstation 425 DECstation 316

Reference Manual DECstation 316

Technical Reference Manual DECstation 425c Technical Reference

Manual DECstation Option Installation Guides

Service Kit PCSA Network Troubleshooting Guide AA-JU54A-TH DECetherWORKS Service Guide EK-DE21A-SV DECconnect System Stand-alone

ThinWire Networks Planning and Installation Guide

DECconnect System Planning and Conﬁguration Guide

DECconnect System Installation and Veriﬁcation Guide

+ User’s Guide ER-PC464-UG C User’s Guide ER-PC462-UG C User’s Guide ER-PC463-UG C User’s Guide ER-PC465-UG

+/325C /333C Technical +/320+/325C /333C

ER-PC46Y-AA ER-PC46Y-DD ER-PC46Y-BA ER-4XOPS-SV

EK-DECSY-TG

EK-DECSY-CG EK-DECSY-VG

x About This Manual

Digital personnel may order documents with part numbers beginning with either ER or EK from:

Digital Equipment Corporation 444 Whitney Street Northboro, MA 01532

Attn: Publishing and Circulation Services (NRO3/W3) Order Processing Section

On-line orders can be sent ALL-IN-1 mail to Order @NRO or VMS mail to NEST::ORDER.

Digital personnel may order documents with part numbers beginning with AA from:

Digital Equipment Corporation Digital Drive

Westminster MA 01473-0471 Attn: Attention: Order Administration Digital self-maintenance customers may order documents with

part numbers beginning with EK, ER, or AA by mail or phone from:

Digital Equipment Corporation

Peripherals and Supplies Group

P.O. Box CS2008

Nashua, NH 03061 Or, by phone call:

1-800-DIGITAL between 8:30am and 8:00pm Eastern Standard Time.

Overview

1.1 Introduction

The DECstation (Figure 1–1) is a desktop computer. It can be used as a standalone personal computer or as a node on a network to a VAX computer or another DECstation with network server software. The DECstation runs Digital and other industrystandard applications.

LJ-1574

Figure 1–1 DECstation Personal Computer

1–1

1–2 Overview

As a node on a Personal Computing System Architecture (PCSA) network, the DECstation is the user’s interface with the applications and services that the PCSA family of products provides. As part of a network, the DECstation communicates with other computers on the network and shares the various resources and services offered by Digital computers and servers.

1.2 DECstation Base System

The DECstation base system unit consists of the following:

• CPU board with:

— 16 MHz 80386 processor (DECstation 316+ — 20 MHz 80386 processor (DECstation 320+) — 25 MHz 80386 processor (DECstation 325C) — 33 MHz 80386 processor (DECstation 333C) — 25 MHz i486 processor (DECstation 425C) — 32 Kilobyte cache memory (DECstation 325C and 333C) — Socket for optional math coprocessor

• Main logic board containing:

— 0K Memory Adapter (containing 1 Mbyte of RAM,

minimum) — Serial and parallel ports — PS/2-type mouse port — Intelligent Drive Electronics (IDE) drive connector — Six 16-bit expansion slots for industry standard options

(usable as 8-bit slots also)

• 200 watt power supply with auxiliary power output (IEC) connector

• 3.5 inch 1.44 Mbyte diskette drive

Overview 1–3

1.3 DECstation Options

The following are options available for the DECstation:

• Color or monochrome VGA analog monitor

• Keyboard (country-speciﬁc)

• 16-bit SCSI host adapter

• 40 Mbyte, 80 Mbyte, 170, or 320 Mbyte SCSI hard disk drive

• 150 Mbyte, SCSI Tape Cartridge System

• 20 Mbyte, 40 Mbyte, 120, or 105 Mbyte IDE hard disk drive

• 60 Mbyte streaming tape drive (QIC-40)

• 16-bit Video Graphics Array (VGA) adapter

• 8514/A-Compatible Graphics adapter

• DEC EtherWORKS bus adapter

• A second 0K memory expansion adapter

1.3.1 System Unit Layout

Figure 1–2 shows the location of both standard and optional equipment within the system unit. Standard, base system equipment is represented by solid lines. Optional equipment is represented by dotted lines.

1–4 Overview

LJ-1714

Figure 1–2 System Unit Layout

1.4 DECstation System Conﬁgurations

The DECstation personal computers are available in two base system conﬁgurations (115 or 230 Vac). These systems are available for customers who elect to purchase DECstation supported options separately and conﬁgure their own systems. Additionally, customers can order one of several packaged systems which offer optional system memory conﬁgurations, mass storage devices, and video adapters installed at the factory.

Overview 1–5

The base system conﬁgurations are listed in Table 1–1.

Table 1–1 Base System Conﬁgurations

Model Number Description

PC461-AA DECstation 316+; 80386/16 MHz, base system box,

0K Memory Adapter with 1 Mbyte RAM (minimum),

3.5" 1.44 Mbyte ﬂoppy disk drive, on-board IDE device interface, serial/parallel port, mouse and keyboard port, 6 PC/AT expansion slots (4 full size; 2 half-size), 2 dedicated 32-bit memory slots, 3 additional front panel storage bays (3.5" or 5.25"), 16-bit VGA adapter, with the power supply factory set at 120 Vac, 60 Hz.

PC461-A2 Same as PC461-AA, but with no power cord or

keyboard.

PC461-A3 Same as PC461-A2, but the power supply is factory set

at 240 Vac, 50 Hz.

PC462-AA DECstation 325

C; 80386/25 MHz base system box, 0K

Memory Adapter with 1 Mbyte RAM (minimum), 3.5"

1.44 Mbyte ﬂoppy disk drive, on-board IDE device interface, serial/parallel port, mouse and keyboard port, 6 PC/AT expansion slots (4 full size; 2 half-size), 2 dedicated 32-bit memory slots, 3 additional front panel storage bays (3.5" or 5.25"), with the power supply factory set at 120 Vac, 60 Hz.

PC462-A2 Same as PC462-AA, but with no power cord or

keyboard.

PC462-A3 Same as PC462-A2, but with no power cord or

keyboard, and the power supply is factory set at 240 Vac, 50 Hz.

1–6 Overview

Table 1–1 (Cont.) Base System Conﬁgurations

Model Number Description

PC463-AA DECstation 333C; 80386/33 MHz base system box, 0K

PC463-A2 Same as PC463-AA, but with the power supply factory

PC463-A3 Same as PC463-A2, but with the power supply factory

PC464-AA DECstation 320+; 80386/20 MHz, base system box,

PC464-A2 Same as PC464-AA, But with no power cord or

Memory Adapter with 1 Mbyte RAM (minimum), 3.5"

set at 120 Vac, 50 Hz.

set at 240 Vac, 50 Hz.

0K Memory Adapter with 1 Mbyte RAM (minimum),

keyboard.

PC464-A3 Same as PC465-A2, but the power supply is factory set

at 240 Vac, 50 Hz.

Table 1–1 (Cont.) Base System Conﬁgurations

Model Number Description

Overview 1–7

PC465-AA DECstation 425C; 80486/25 MHz, base system box,

PC465-A2 Same as PC465-AA, But with no power cord or

PC465-A3 Same as PC465-A2, but the power supply is factory set

0K Memory Adapter with 1 Mbyte RAM (minimum),

keyboard.

at 240 Vac, 50 Hz.

1.4.1 DECstation Main Logic Board

The DECstation main logic board contains a ﬂoppy disk controller, serial and parallel ports, PS/2-style mouse port, IDE drive connector, six 16-bit expansion slots (usable as 8-bit also), and two dedicated 32-bit memory expansion slots (one slot contains a 0K Memory Adapter with 1 Mbyte of RAM minimum).

1.4.2 DECstation 316+ CPU Board

The CPU board of the DECstation 316+ contains a 16 MHz Intel 80386 CPU chip and a socket for an optional Intel 80387 math coprocessor. No cache memory is provided on the DECstation 316+.

1.4.3 DECstation 325C CPU Board

The CPU board of the DECstation 325C contains a 25 MHz Intel 80386 CPU chip, 32 Kbytes of cache memory, and a socket for an optional Intel 80387 math coprocessor.

1–8 Overview

1.4.4 DECstation 333C CPU Board

The CPU board of the DECstation 333C contains a 33 MHz Intel 80386 CPU chip, 32 Kbytes of cache memory, and a socket for an optional Intel 80387 math coprocessor.

1.4.5 DECstation 320+ CPU Board

The CPU board of the DECstation 320+ contains a 20 MHz Intel 80386 CPU chip and a socket for an optional Intel 80387 math coprocessor. No cache memory is provided on the DECstation 320+.

1.4.6 DECstation 425C CPU Board

The CPU board of the DECstation 425C contains a 25 MHz Intel i486 CPU chip and a socket for an optional 25 MHz WIETEK 4167 math coprocessor. No external cache memory is provided on the DECstation 320+. The Intel i486 CPU has an integral 8 Kbyte cache memory.

1.4.7 Power Supply

The DECstation is supplied with a 200 watt power supply that includes an auxiliary ac power output (IEC) connector. The power supply is switch selectable between either 115 Vac, 60 Hz or 230 Vac, 50/60 Hz power input.

1.4.8 Monitors

The DECstation supports both color and monochrome VGA analog monitors. The monitors are available in different voltage input variations and video alignments to meet international requirements. See Table 1–2.

Table 1–2 Monitors

Model Number Part Number Description

Overview 1–9

PC4XV-AA 30-32317-01 VGA monochromatic 14" for all

PC4XV-A2 30-32317-02 VGA monochromatic 14"

PC4XV-A3 30-32319-01 VGA monochromatic 14"

PC4XV-A4 30-32320-01 VGA monochromatic 14"

PC4XV-A5 30-32318-01 VGA monochromatic 14"

PC4XV-A6 30-33966-01 VGA monochromatic RGB 14"

versions of DECstation personal computers. Requires PC4XG-AA or -AB VGA adapter, except on the PC44- models. Displays 64 shades of grey, 640 x 480 resolution. 120 Vac 60 Hz (US and Canada)

International Version, 120 Vac 60 Hz, with 640 x 480 resolution, North Hemisphere (IEC Plug)

international version, 240 Vac 50 Hz, with 640 x 480 resolution, North Hemisphere (IEC Plug)

international version, 240 Vac 50 Hz, with 640 x 480 resolution, South Hemisphere (IEC Plug)

international version, 120 Vac 60 Hz, with 640 x 480 resolution, South Hemisphere (IEC Plug)

international version, 240 Vac 50 Hz, with 640 x 480 resolution, North Hemisphere (IEC Plug)

PC4XV-A7 30-33967-01 VGA monochromatic RGB 14"

international version, 240 Vac 50 Hz, with 640 x 480 resolution, South Hemisphere (IEC Plug)

1–10 Overview

Table 1–2 (Cont.) Monitors

Model Number Part Number Description

PC4XV-BA 30-30901-01 VGA monochromatic RGB 14" for

PC4XV-B2 30-32313-01 VGA monochromatic RGB 14"

PC4XV-B3 30-32315-01 VGA monochromatic RGB 14"

PC4XV-B4 30-32316-01 VGA monochromatic RGB 14"

PC4XV-B5 30-32314-01 VGA monochromatic RGB 14"

PC4XV-B6 30-33968-01 VGA monochromatic RGB 14"

all versions of DECstation personal computers. Requires PC4XG-AA or -AB VGA adapter, except on the PC44- models, 120 Vac 60 Hz (US and Canada), with 640 x 480 resolution.

international version, 120 Vac 60 Hz, with 1024 x 768 resolution, North Hemisphere (IEC Plug)

international version, 240 Vac 50 Hz, with 640 x 480 resolution, North Hemisphere (IEC Plug)

international version, 240 Vac 50 Hz, with 640 x 480 resolution, South Hemisphere (IEC Plug)

international version, 120 Vac 60 Hz, with 1024 x 768 resolution, South Hemisphere (IEC Plug)

international version, 240 Vac 50 Hz, with 1024 x 768 resolution, North Hemisphere (IEC Plug)

PC4XV-B7 30-33969-01 VGA monochromatic RGB 14"

international version, 240 Vac 50 Hz, with 1024 x 768 resolution, South Hemisphere (IEC Plug)

Overview 1–11

1.4.9 Video Graphics Array Adapter

The Video Graphics Array (VGA) adapter provides the video display control functions of the DECstation. The VGA adapter is available in 8-bit or 16-bit (800 x 600 resolution) models, and is also compatible with the following video standards. (Note: There is also a 16-bit VGA 1024 x 768 resolution model available).

• MCGA - Multi-color Graphics Array

• EGA - IBM Extended Graphics Adapter

• CGA - IBM Color Graphics Adapter

• MDA - IBM Monochrome Display Adapter

• Hercules graphics - Hercules graphic card

The VGA adapter can run software written for any of the video standards on any supported monitor. For example, you can run monochrome or color software on supported DECstation color monitors. The VGA also supports 132 column text mode. The text mode and color or monochrome mapping can be set by using the VGA.EXE utility supplied with the system.

1.4.10 Enhanced Keyboards

There are two different keyboards that are available as options on the DECstation: The 101-key enhanced keyboard, and the LK250 keyboard.

NOTE

Keyboards used with the DECstation must be equipped with a 6-pin miniature PS/2-style connector.

1.4.10.1 101-Key Enhanced Keyboard

The 101-key enhanced keyboard provides the industry-standard IBM-PC/AT-style key arrangement on a smaller, desktop keyboard.

1–12 Overview

1.4.10.2 LK250 Keyboard

The LK250 keyboard provides the standard Digital key arrangement available in several country-speciﬁc language variations.

1.4.11 Math Coprocessor

The optional math coprocessors listed in Table 1–3 plug into the main logic board and allow each DECstation to process numeric data faster.

Table 1–3 Math Coprocessors

Model Number Description

PC43P-AA 20 MHz Intel 80387 coprocessor for the DECstation

+ (also compatible with DECstation 320)

320

PC46P-AA 16 MHz Intel 80287 coprocessor for the DECstation

316

PC46P-BB 25 MHz Intel 80387 coprocessor for the DECstation

325

PC46P-CC 33 MHz Intel 80287 coprocessor for the DECstation

333

PC46P-EE 25 MHz WIETEK 4167 coprocessor for the DECstation

425

Troubleshooting

This chapter provides troubleshooting instructions for the DECstation systems. It is divided into the following sections:

• Special tools

• Diagnostics

• Normal power up

• Troubleshooting procedures

• Error codes and how to use them

• Troubleshooting by symptom

• Troubleshooting during system operation

• Using the System Utilities diskette

For information about jumper settings, troubleshooting, and servicing of the DEC EtherWORKS option board and related network connections refer to the DEC EtherWORKS Service Guide.

2.1 Special Tools

The special tools needed to troubleshoot the DECstation system are given in Table 2–1.

2–1

2–2 Troubleshooting

Table 2–1 Troubleshooting Tools

Tool Part Number Deﬁnition

Diagnose

Diagnostics (Version 3.0)

Tri-wrap Loopback Connector

DECstation

+ Utilities

316 Diskette

DECstation

+ Utilities

320 Diskette

DECstation

C Utilities

325 Diskette

DECstation

C Utilities

333 Diskette

29-27462-01 These standalone diagnostics

are available separately. For information about using these diagnostics, refer to the accompanying manual.

FD-10164-00 This triple connector consists

of a male 25-pin parallel loopback connector, a female 25-pin serial loopback connector, and a female 9pin serial loopback connector bundled together and housed in a streamlined package.

29-28153-01 Used to reconﬁgure the CPU

when options are installed.

29-28852-01 Used to reconﬁgure the CPU

when options are installed.

29-28101-01 Used to reconﬁgure the CPU

when options are installed.

29-28152-01 Used to reconﬁgure the CPU

when options are installed.

DECstation

C Utilities

425 Diskette

2.2 Diagnostics

The DECstation has internal ROM-based diagnostics to aid in troubleshooting. These diagnostics are run at system power-up and verify the operation of the machine. Error messages are given in two formats: Beep codes and messages displayed on the screen. These error messages are explained in Section 2.5.

29-28678-01 Used to reconﬁgure the CPU

when options are installed.

Troubleshooting 2–3

2.3 Normal Power Up

In a normal system power up the following takes place:

1. Power to the monitor and system unit is turned on. Both power indicators are on.

2. The system executes its power-up tests, displays the BIOS ROM version, assorted copyright information, and the memory size. Depending on the option(s) installed in the system additional information may be displayed.

If there is an error during any of the power-up tests the system either generates a beep error code or displays an error message.

3. The system generates a single beep, displays information about the operating system, and gives the date prompt. Note that the actual information displayed at this time depends on the system software.

2.4 Troubleshooting Procedures

This section describes three troubleshooting procedures that can be used depending on the state of the system. Each procedure will get the system to a state where it can run the Diagnose diagnostic package. Perform the steps in Section 2.4.1 and then go to the recommended procedure.

CAUTION

Before troubleshooting the DECstation, it must be disconnected from any network.

2.4.1 Getting Started

The following steps prepare you for troubleshooting a DECstation:

1. Ask the customer to describe the problem. You need to ﬁnd out:

— When the problem started

2–4 Troubleshooting

— If any new hardware options were added to the system

around the time the problem started and if the options are Digital certiﬁed or third party

— If any new software was added to the system

2. Have the customer supply you with a copy of the operating system diskette(s) that came with the system.

3. Have the customer provide you with the system conﬁguration.

— Type of monitor — Type of keyboard — Type and number of disk drives — Type and amount of memory — Type of network adapter — Type of mouse — Type of disk adapter (if on-board disk adapter is disabled) — Type of video graphics adapter (if on-board VGA is

disabled)

— Any other options installed in the system

4. Observe the problem. Based on what you observe refer to one of the following procedures:

— If the system does not power up see Section 2.4.2, No

Power.

— If the system powers up but will not boot see Section 2.4.3,

System Does Not Boot.

— If the system powers up and boots see Section 2.4.4,

System Boots.

Troubleshooting 2–5

2.4.2 No Power

This procedure helps determine the cause of the problem when the DECstation does not power up. Before starting this procedure be sure you have done the steps in Section 2.4.1.

1. Check the system for loose cables and connections.

2. Check the 115/230 Vac switch on the back of the system unit.

3. Plug the system unit and monitor power cord into a working ac outlet.

4. Turn on power to the monitor and system unit. Check for system power. The following are indications that the system and monitor have powered up:

— Power indicators on the system unit and monitor are on. — You can hear the fan running. — You can hear the hard disk spinning.

5. If the system does not power up: a. Turn off power to the system unit and monitor. b. Unplug the system and monitor from the ac outlet. c. Disconnect power to all the hard disk drives and remove

all options. d. Plug the monitor and system into a working ac outlet. e. Turn the monitor and system power on. If the system

powers up there was either a faulty device, too many

options installed, or another power related problem. f. Try booting the system from the operating system startup

diskette. g. Replace the Digital certiﬁed options one at a time and see

if the system powers up each time an option is replaced or

a disk drive is reconnected.

6. If the system powers up and does not boot refer to Section 2.4.3.

+ 65 hidden pages

DEC DECstation 316+, DECstation 325c, DECstation 333c, DECstation 320+, DECstation 425c Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual