GE Marquette MAC 5000 User manual

Download

MAC 5000 resting ECG

analysis system

field service manual

PN 2000657-002 Revision A

T-2

MAC 5000 resting ECG analysis system

field service manual

PN 2000657-002 Revision B

NOTE

Due to continuing product innovation, specifications in this manual are subject to change without notice.

MD1322-018



Trademarked names appear throughout this document. Rather than list the names and entities that own the trademarks or insert a trademark symbol with each mention of the trademarked name, the publisher states that it is using the names only for editorial purposes and to the benefit of the trademark owner with no intention of improperly using the trademark.

900 SC, ACCUSKETCH, AccuVision, APEX, AQUA-KNOT, ARCHIVIST, Autoseq, BABY MAC, C Qwik Connect, CardioServ, CardioSmart, CardioSys, CardioWindow, CASE, CD TELEMETRY, CENTRA, CHART GUARD, CINE 35, CORO, COROLAN, COROMETRICS, Corometrics Sensor Tip, CRG PLUS, DASH, Digistore, Digital DATAQ, E for M, EAGLE, Event-Link, FMS 101B, FMS 111, HELLIGE, IMAGE STORE, INTELLIMOTION, IQA, LASER SXP, MAC, MAC-LAB, MACTRODE, MANAGED USE, MARQUETTE, MARQUETTE MAC, MARQUETTE MEDICAL SYSTEMS, MARQUETTE UNITY NETWORK, MARS, MAX, MEDITEL, MEI, MEI in the circle logo, MEMOPORT, MEMOPORT C, MINISTORE, MINNOWS, Monarch 8000, MULTI-LINK, MULTISCRIPTOR, MUSE, MUSE CV, Neo-Trak, NEUROSCRIPT, OnlineABG, OXYMONITOR, Pres-R-Cuff, PRESSURE-SCRIBE, QMI, QS, Quantitative Medicine, Quantitative Sentinel, RAC RAMS, RSVP, SAM, SEER, SILVERTRACE, SOLAR, SOLARVIEW, Spectra 400, Spectra-Overview, Spectra-Tel, ST GUARD, TRAM, TRAM-NET, TRAM-RAC, TRAMSCOPE, TRIM KNOB, Trimline, UNION STATION, UNITY logo, UNITY NETWORK, Vari-X, Vari-X Cardiomatic, VariCath, VARIDEX, VAS, and Vision Care Filter are trademarks of GE Marquette Medical Systems, Inc. registered in the United States Patent and Trademark Office.

12SL, 15SL, Access, AccuSpeak, ADVANTAGE, BAM, BODYTRODE, Cardiomatic, CardioSpeak, CD TELEMETRY Link Nimbus, HI-RES, ICMMS, IMAGE VAULT, IMPACT.wf, INTER-LEAD, IQA, LIFEWATCH, Managed Use, MARQUETTE PRISM, MARQUETTE NST PRO, NAUTILUS, O

-LAN, CENTRALSCOPE, Corolation, EDIC, EK-Pro, Event-Link Cirrus, Event-Link Cumulus, Event-

RESPONDER, MENTOR, MicroSmart, MMS, MRT, MUSE CardioWindow,

SENSOR, Octanet, OMRS, PHi-Res, Premium, Prism, QUIK CONNECT V, QUICK

CONNECT, QT Guard, SMART-PAC, SMARTLOOK, Spiral Lok, Sweetheart, UNITY, Universal, Waterfall, and Walkmom are trademarks of GE Marquette Medical Systems, Inc.

T-2

MAC 5000 resting ECG analysis system

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Revision B

24 January 2000

Contents

1 Introduction ................................................. 1-1

Manual Information .................................................................. 1-3

Revision History ................................................................................. 1-3

Manual Purpose ................................................................................. 1-3

Intended Audience ............................................................................. 1-3

Conventions ....................................................................................... 1-4

Safety Information .................................................................... 1-5

Definitions .......................................................................................... 1-5

Messages ........................................................................................... 1-5

Responsibility of the Manufacturer .................................................... 1-6

General .............................................................................................. 1-6

Equipment Symbols ........................................................................... 1-7

Service Information .................................................................. 1-8

Service Requirements ........................................................................ 1-8

Equipment Identification .................................................................... 1-8

2 Equipment Overview ...................................... 2-1

General Description .................................................................. 2-3

Front View .......................................................................................... 2-3

Back View .......................................................................................... 2-3

Internal View ...................................................................................... 2-4

Preparation for Use ................................................................... 2-5

Trolley Assembly ............................................................................... 2-5

Connector Identification ..................................................................... 2-6

Paper Installation ............................................................................... 2-7

Controls and Indicators ...................................................................... 2-8

Revision B

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3 Maintenance ................................................ 3-1

Introduction ...................................................................... 3-3

Recommended Maintenance .............................................................. 3-3

Preventive Maintenance Inspection Report ........................................ 3-3

Required Tools and Supplies ............................................................. 3-3

Inspection and Cleaning ............................................................. 3-4

Visual Inspection ............................................................................... 3-4

Exterior Cleaning ................................................................................ 3-4

Interior Cleaning ................................................................................ 3-4

General ................................................................................. 3-4

Thermal Printhead ................................................................ 3-5

Battery and Patient Cable Replacement .......................................... 3-6

Battery Replacement .......................................................................... 3-6

Patient Cable Replacement ................................................................ 3-6

Disassembly Guidelines ............................................................. 3-7

Preliminary Steps ............................................................................... 3-7

Power Supply ..................................................................................... 3-7

Removal ............................................................................... 3-7

Reassembly .......................................................................... 3-8

Top Cover .......................................................................................... 3-8

Removal ............................................................................... 3-8

Reassembly .......................................................................... 3-9

Display/Keyboard Assembly ............................................................... 3-9

Removal ............................................................................... 3-9

Reassembly ........................................................................ 3-11

Main PCB ......................................................................................... 3-11

Removal ............................................................................. 3-11

Reassembly ........................................................................ 3-11

Diskette Drive Removal/Replacement .............................................. 3-12

Writer Roller/Carriage Assembly ...................................................... 3-12

Removal ............................................................................. 3-12

Reassembly ........................................................................ 3-12

Domestic Electrical Safety Tests .................................................. 3-13

AC Line Voltage Test ........................................................................ 3-13

120 VAC, 50/60 Hz ............................................................. 3-13

240 VAC, 50/60 Hz ............................................................. 3-13

Leakage Tests .................................................................................. 3-14

Leakage Test Diagrams .................................................................... 3-15

Test #1 ............................................................................................. 3-15

Test #2 ............................................................................................. 3-15

Test #3 ............................................................................................. 3-16

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Revision B

Test #4 ............................................................................................. 3-16

Ground Continuity ............................................................................ 3-17

Preventive Maintenance ............................................................ 3-18

4 Troubleshooting ........................................... 4-1

Assembly Descriptions ............................................................... 4-3

Introduction ....................................................................................... 4-3

Assembly Block Diagram ................................................................... 4-3

Input and Output Connectors ........................................................ 4-4

A Pins (J1) ......................................................................................... 4-4

COM1 (COM3/4) Pins (J3) ................................................................. 4-4

COM2 Pins (J5) ................................................................................. 4-4

ANALOG Pins (J6) ............................................................................. 4-5

EXT. VID. Pins (J7) ............................................................................ 4-5

Internal Cabling ...................................................................... 4-6

CPU PCB Input/Output Signals ...................................................... 4-8

Battery Pack/Monitor (J2) .................................................................. 4-8

LCD Backlight (J4) ............................................................................. 4-8

Keyboard (J8) .................................................................................... 4-9

LCD (J10) ........................................................................................ 4-10

Power Supply/Motor (J11) ............................................................... 4-11

Thermal Printer (J12) ....................................................................... 4-12

Floppy Disk Drive (J13) .................................................................... 4-13

Acquisition Module (J14) ................................................................. 4-13

Revision B

General Fault Isolation ............................................................. 4-14

Visual Inspection .............................................................................. 4-14

Power-up Self-test ........................................................................... 4-14

Power-up Flow Chart ....................................................................... 4-15

Poor Quality ECGs ............................................................................ 4-15

Diagnostic Tests ..................................................................... 4-16

Introduction ..................................................................................... 4-16

Loading the System Diagnostics ...................................................... 4-16

System Diagnostics Main Menu ....................................................... 4-17

Display Tests .................................................................................... 4-17

Pixel Verification Test ......................................................... 4-17

Grey Scale Test Patterns ..................................................... 4-17

Anti-Aliasing Test Pattern ................................................... 4-18

Speaker Test .................................................................................... 4-18

Keyboard Test .................................................................................. 4-18

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iii

Writer Tests ..................................................................................... 4-19

C-Scan Test 1

C-Scan Test 2

C-Scan Test 3 ..................................................................... 4-19

50 mm/s Test Pattern I

25 mm/s Test Pattern I

5 mm/s Test Pattern I ......................................................... 4-19

Roller Test .......................................................................... 4-20

Test Pattern II ..................................................................... 4-20

Test Pattern II Continuous .................................................. 4-20

Continuously Run Out Paper .............................................. 4-20

Battery Tests .................................................................................... 4-20

Battery Status ..................................................................... 4-20

Battery Discharge Test ....................................................... 4-21

Battery Charge Test ............................................................ 4-21

Print Discharge Test Results

Print Charge Test Results ................................................... 4-21

Communication Tests ...................................................................... 4-21

COM Port Loopback Test .................................................... 4-21

Modem Test ....................................................................... 4-22

Acq. Module Tests ........................................................................... 4-22

Analog I/O Tests .............................................................................. 4-22

Analog Output Test ............................................................. 4-22

Analog Input Test ............................................................... 4-22

DCOut Loopback Test ......................................................... 4-22

Floppy Drive Tests ........................................................................... 4-22

5 CPU Theory of Operation ................................. 5-1

General Description .................................................................. 5-3

Block Diagram ................................................................................... 5-4

Theory of Operation .................................................................. 5-6

Clocks ................................................................................................ 5-6

CPU .................................................................................................... 5-6

FPGA .................................................................................................. 5-6

Bootstrap Instruction Unpacker ............................................ 5-7

EDO DRAM Controller .......................................................... 5-7

XBus Controller .................................................................... 5-7

LCD Controller VLB Bus Cycle Interface ............................... 5-7

Video Waveform Scrolling .................................................... 5-8

Interrupt Controller ............................................................... 5-9

System Interrupt Generator .................................................. 5-9

Acquisition Module Interface ................................................ 5-9

Thermal Printhead Interface ............................................... 5-10

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Revision B

Serial EEPROM Interface .................................................... 5-10

BBus Interface .................................................................... 5-10

UARTS ................................................................................ 5-11

PWM Analog Outputs ......................................................... 5-11

Beep Generator ................................................................... 5-11

DRAM .............................................................................................. 5-12

SmartMedia Card ............................................................................. 5-12

Serial EEPROM ................................................................................ 5-12

VGA LCD/CRT Interface ................................................................... 5-12

Acquisition Module Transceiver/Power Switch ................................ 5-12

Thermal Printhead Power/Pixel Test Logic ....................................... 5-12

SuperIO Peripheral Controller .......................................................... 5-13

Floppy Drive Support .......................................................... 5-13

Four RS-232 Serial Ports (one dual mode RS-232/IrDA) ... 5-13

Clock/Calendar .................................................................... 5-13

External PS-2 Keyboard Port .............................................. 5-13

General Purpose Parallel I/O Lines ..................................... 5-13

The Four Stooges ............................................................................. 5-13

Startup Self Identification ................................................... 5-14

BBus ................................................................................... 5-14

Curly ................................................................................... 5-14

Shemp ................................................................................ 5-14

Larry ................................................................................... 5-15

Moe .................................................................................... 5-15

Untested "Nominal" Operating Time Specs ....................................... 5-19

Revision B

6 Parts Lists and Drawings ................................ 6-1

Ordering Parts ......................................................................... 3

Introduction ........................................................................................... 3

Field Replaceable Units ................................................................ 4

MAC 5000Rev B Generic Assembly .................................................. 5

900769-001F Generic Assembly .................................................. 9

421117-001A Power Supply Assembly ........................................ 18

421114-002A Display Assembly ............................................... 20

900997-001C Trolley ............................................................. 24

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7 PCB Assemblies ............................................ 7-1

801212-003A CPU PCB Assembly ................................................ 3

SD801212-003A CPU ................................................................. 10

801220-001B Battery Transition PCB .......................................... 26

SD801220-001A Battery Transition ................................................ 27

801222-001A LED PCB ........................................................... 28

SD801222-001A LED ................................................................. 29

2001326-001A Motor Protect PCB ............................................... 31

2001326-001A Motor Protect ..................................................... 32

Appendices Appendix A: Abbreviations ............................... A-1

Standard Abbreviations .............................................................. A-3

Appendix B: Technical Specifications .................. B-1

Technical Specifications ............................................................ B-3

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Revision B

1 Introduction

Manual Information ..................................................................... 3

Revision History ..................................................................................... 3

Manual Purpose ..................................................................................... 3

Intended Audience ................................................................................. 3

Conventions ........................................................................................... 4

Safety Information ....................................................................... 5

Definitions .............................................................................................. 5

Messages ............................................................................................... 5

Responsibility of the Manufacturer ........................................................ 6

General .................................................................................................. 6

Equipment Symbols ............................................................................... 7

Service Information ..................................................................... 8

Service Requirements ............................................................................ 8

Equipment Identification ........................................................................ 8

Revision B

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1-1

1-2

MAC 5000 resting ECG analysis system

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Revision B

Manual Information

Introduction: Manual Information

Revision History

Revision Date Comment

A 27 August 1999 Initial release. Replaces pn 418625-002.

B 24 January 2000 Added Printhead Replacement procedure in Chapter 3. Added illustration and updated

Diskette Drive Replacement in Chapter 3. Updated Chapters 6 & 7 with latest drawings.

Manual Purpose

Each page of the document has the document part number and revision letter at the bottom of the page. The revision letter identifies the

document’s update level.

The revision history of this document is summarized in the table below.

Table 1-1. Revision History PN 2000657-002

This manual supplies technical information for service representative and technical personnel so they can maintain the equipment to the assembly level. Use it as a guide for maintenance and electrical repairs considered field repairable. Where necessary the manual identifies additional sources of relevant information and or technical assistance.

See the operator’s manual for the instructions necessary to operate the equipment safely in accordance with its function and intended use.

Intended Audience

This manual is intended for the person who uses, maintains, or troubleshoots this equipment.

Revision B 1-3

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Introduction: Manual Information

Conventions

Table 1-2. Styles

Style Definition

Black text Indicates keys on the keyboard, text to be entered,

or hardware items such as buttons or switches on the equipment.

Italicized

text Indicates software terms that identify menu items,

buttons or options in various windows.

Ctrl+Esc Indicates a keyboard operation. A (+) sign between

between the names of two keys indicates, you press and hold the first key while pressing the second key once.

For example, “Press Ctrl+Esc” means to press and hold down the Ctrl key while pressing the Esc key.

<Space> Indicates that you must press the spacebar.

When instructions are given for typing a precise text string with one or more spaces, the point where the spacebar must be pressed is indicated as: <Space>. The purpose of the < > brackets is to ensure you press the spacebar when required.

Enter Indicates that you must press the “Enter” or

“Return” key on the keyboard. Do not type “enter”.

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Revision B1-4

Safety Information

Introduction: Safety Information

Definitions

Messages

DANGER

Do NOT use in the presence of flammable anesthetics.

DANGER

Indicates an imminently hazardous situation which, if not avoided, WILL result in death or serious injury.

WARNING

Indicates a potentially hazardous situation which, if not avoided, COULD result in death or serious injury.

CAUTION

Indicates a potentially hazardous situation which, if not avoided may result in minor or moderate injury.

Additional safety messages may be found throughout this manual that provide appropriate safe operation information.

WARNING

Operate the unit from its battery if the integrity of

M15287-1B

the protective earth conductor is in doubt.

M15287-14C

WARNING

This is Class I equipment. The mains plug must be connected to an appropriate power supply.

CAUTION

This equipment contains no user serviceable parts. Refer servicing to qualified service personnel.

M15287-5C

M15287-38A

CAUTION

U.S. Federal law restricts this device to sale by or on the order of a physician.

M15287-17B

Revision B 1-5

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Introduction: Safety Information

Responsibility of the

Manufacturer

General

GE Marquette Medical Systems is responsible for the effects of safety, reliability, and performance only if:

■ Assembly operations, extensions, readjustments, modifications,

or repairs are carried out by persons authorized by Marquette.

■ The electrical installation of the relevant room complies with

the requirements of the appropriate regulations.

■ The equipment is used in accordance with the instructions for

use.

The intended use of this device is to record ECG signals from surface ECG electrodes. This device can analyze, record, and store electrocardiographic information from adult and pediatric populations. This data can then be computer analyzed with various algorithms such as interpretive ECG and signal averaging for presentation to the user.

This device is intended for use under the direct supervision of a licensed health care practitioner.

Failure on the part of the responsible individual, hospital, or institution using this equipment to implement a satisfactory maintenance schedule may cause undue equipment failure and possible health hazards.

To ensure patient safety, use only parts and accessories manufactured or recommended by GE Marquette Medical Systems.

Contact GE Marquette Medical Systems for information before connecting any devices to this equipment that are not recommended in this manual.

If the installation of this equipment, in the USA, will use 240 V rather than 120 V, the source must be a center-tapped, 240 V, single-phase circuit.

Parts and accessories used must meet the requirements of the applicable IEC 601 series safety standards, and/or the system configuration must meet the requirements of the IEC 601-1-1 medical electrical systems standard.

The use of ACCESSORY equipment not complying with the equivalent safety requirements of this equipment may lead to a reduced level of safety of the resulting system. Consideration relating to the choice shall include:

■ use of the accessory in the PATIENT VICINITY; and

■ evidence that the safety certification of the ACCESSORY has

been performed in accordance to the appropriate IEC 601-1 and/or IEC 601-1-1 harmonized national standard.

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Revision B1-6

Introduction: Safety Information

Equipment Symbols

The following symbols appear on the equipment.

Type B equipment.

Type BF equipment, external defibrillator protected.

Alternating current. When illuminated, the green LED next to this symbol indicates AC power is connected.

Equipotential.

Charge the battery. The flashing amber LED next to this symbol indicates you must connect the system to AC power to re-charge the battery.

MEDICAL EQUIPMENT

UL 2601-1 CAN/CSA 601.1

4P41

DO NOT throw the battery into the garbage.

Recycle the battery.

Consult accompanying documents.

Classified with respect to electric shock, fire, mechanical, and other specified hazards only in accordance with UL 2601-1, CAN/CSA C22.2 No. 601-1, CAN/CSA C22.2 601-2-25, EN 60601-2-25, EN 60601-1-1.

In Europe, this symbol means dangerous or high voltage. In the United States, this symbol represents the caution notice below:

CAUTION

To reduce the risk of electric shock, do NOT remove cover (or back). Refer servicing to qualified personnel.

M15287-16A

MD1325-097A, -098A, -096A, -108A, -101A, -102A, -103A, -100A, -181A, -099A

Revision B 1-7

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Introduction: Service Information

Service Information

Service Requirements

Equipment Identification

Refer equipment servicing to GE Marquette Medical System’s authorized service personnel only. Any unauthorized attempt to repair equipment under warranty voids that warranty.

It is the user’s responsibility to report the need for service to GE Marquette Medical Systems or to one of their authorized agents.

Every GE Marquette Medical Systems device has a unique serial number for identification. The serial number appears on the product label on the base of each unit.

XXXXXXXXX

XXXXXXXX XXXXXXX XXXXXXX XXX

XXXXXXXXX XX XXXX XX XXXXX

J6XX0415FXX

Table 1-3. Equipment Identifications

A B

MD1113-022C

Item Name Description

A name of device MAC 5000 resting ECG analysis system

B manufacturer GE Marquette Medical Systems, Inc.

C serial number Unique identifier

D device characteristics One or two letters that further describe the unit, for example: P = prototype not

conforming to marketing specification; R = refurbished equipment; S = special product documented under Specials part numbers; U = upgraded unit

E division F = Cardiology G = Monitoring J = GW Labs

F product sequence number Manufacturing number (of total units manufactured)

G product code Two-character product descriptor MH = MAC 5000 resting ECG analysis system

H year manufactured 9 = 1999, 0 = 2000, 1 = 2001, (and so on)

I month manufactured A = January, B = February, C = March, D = April, E = May, F = June, G = July,

H = August, J = September, K = October, L = November, M = December

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Revision B1-8

2 Equipment Overview

General Description ..................................................................... 3

Front View .............................................................................................. 3

Back View .............................................................................................. 3

Internal View .......................................................................................... 4

Preparation for Use ...................................................................... 5

Trolley Assembly ................................................................................... 5

Connector Identification ......................................................................... 6

Paper Installation ................................................................................... 7

Controls and Indicators .......................................................................... 8

Revision B

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2-1

2-2

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Revision B

General Description

Front View

Equipment Overview: General Description

The MAC 5000 resting ECG analysis system is a 15 lead, 12 channel system with a 10.4 inch (264 mm) diagonal display, active patient cable, battery operation, and late potential electrocardiography. There are also options for wireless communication, vector, and network capabilities.

Display

Back View

Back panel

connectors

AC power

light

Battery

light

Keyboard

Internal

access

button

Disk drive slot

MD1325-115A

MD1325-117A

Revision B 2-3

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Equipment Overview: General Description

Internal View

Battery

Paper tray

MD1325-116A

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Revision B2-4

Preparation for Use

Equipment Overview: Preparation for Use

Trolley Assembly

1. Mount the unit to the optional trolley by lining up the left edge of the unit to the two slots at the left edge of the trolley.

MD1325-171A

2. Place the unit on the trolley surface, then slide it to the left until the tabs click and the unit is firmly in place on the trolley.

3. From under the trolley, tighten two captive screws.

MD1325 -172A

Revision B 2-5

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Equipment Overview: Preparation for Use

Connector Identification

ABC D E F HGI

MD1325-118

Table 2-1. Back Panel Connectors

Item Name Description

A A Not functional.

B 1 Connect a Marquette KISS pump (optional).

C 2 Connect a local transmission cable, serial line,

Marquette KISS pump, or external modem (optional).

WARNING

Keep leakage current within acceptable limits when connecting auxiliary equipment to this device.

D ANA/TTL Connect a device requiring analog data or TTL

trigger.

E EXT.VID. Connect an external video display.

F IR Point at a MAC 5000 or MUSE CV system’s IR

transceiver to transmit or receive ECG data.

G card slot Insert the software card into this slot to run the

system.

H ground lug Connect non-grounded peripheral devices to ensure

equipotential.

I mains AC

Insert the mains AC power cable.

power

WARNING

Total system leakage current must not exceed 100 microamperes.

M15287-7C

M15287-9D

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Revision B2-6

Equipment Overview: Preparation for Use

Paper Installation

1. Press the internal access button to open the unit.

MD1325-092B

2. Slide a stack of paper into the writer compartment with the paper cue hole toward the internal access button.

3. Pull out the top sheet of paper from the stack.

4. Close the unit.

MD1325 -093B

MD1325-094B

MD1325-095B

Revision B 2-7

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Equipment Overview: Preparation for Use

Controls and Indicators

F1 F2 F3 F4 F5 F6

QWE RTY U I O

esc

ZXCVBNM

5678

DFGH

()

+ =

;

off on

Table 2-2. Keypad

Item Name Description

A function keys Selects screen menu functions

copy

ECG

rhythm

stop

C D

E F

MD1325-152A

B delete Erases typed characters

C copy Prints another ECG report

D ECG Acquires an ECG

E rhythm Prints continuous ECG data (This data cannot

be stored or transmitted.)

F stop Stops the writer from printing

G arrow pad Moves the cursor left, right, up, down and

selects a highlighted menu or screen item.

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Revision B2-8

3 Maintenance

Introduction ............................................................................... 3

Recommended Maintenance .................................................................. 3

Preventive Maintenance Inspection Report ............................................ 3

Required Tools and Supplies ................................................................. 3

Inspection and Cleaning ................................................................ 4

Visual Inspection ................................................................................... 4

Exterior Cleaning .................................................................................... 4

Interior Cleaning .................................................................................... 4

General .....................................................................................4

Thermal Printhead ....................................................................5

Battery and Patient Cable Replacement ............................................. 6

Battery Replacement .............................................................................. 6

Patient Cable Replacement .................................................................... 6

Disassembly Guidelines ................................................................ 7

Preliminary Steps ................................................................................... 7

Power Supply ......................................................................................... 7

Removal ...................................................................................7

Reassembly ..............................................................................8

Top Cover .............................................................................................. 8

Removal ...................................................................................8

Reassembly ..............................................................................9

Display/Keyboard Assembly ................................................................... 9

Removal ...................................................................................9

Reassembly ............................................................................11

Main PCB ............................................................................................. 11

Removal ................................................................................. 11

Reassembly ............................................................................11

Printhead Replacement......................................................................... 11

Removal ................................................................................. 11

Reassembly ............................................................................11

Diskette Drive Removal/Replacement .................................................. 12

Writer Roller/Carriage Assembly .......................................................... 12

Removal ................................................................................. 12

Reassembly ............................................................................12

Revision B

Domestic Electrical Safety Tests .................................................... 13

AC Line Voltage Test ............................................................................ 13

120 VAC, 50/60 Hz .................................................................13

240 VAC, 50/60 Hz .................................................................13

Leakage Tests ...................................................................................... 14

Leakage Test Diagrams ........................................................................ 15

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3-1

Test #1 ................................................................................................. 15

Test #2 ................................................................................................. 15

Test #3 ................................................................................................. 16

Test #4 ................................................................................................. 16

Ground Continuity ................................................................................ 17

Preventive Maintenance............................................................... 18

3-2

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Revision B

Introduction

Maintenance: Introduction

Recommended

Maintenance

Preventive Maintenance

Inspection Report

Regular maintenance, irrespective of usage, is essential to ensure that the equipment will always be functional when required.

NOTE

Unless you have an Equipment Maintenance Contract, GE Marquette Medical Systems does not in any manner assume the responsibility for performing the recommended maintenance procedures. The sole responsibility rests with the individual or institution using the eq uipment. GE Marquette Medical Systems service personnel may , at their discretion, f ollow the procedures provided in this manual as a guide during visits to the equipment site.

To help you establish a systematic maintenance routine, GE Marquette Medical Systems recommends that, every six months, you perform the

maintenance checks and test procedures on the “Preventive Maintenance Inspection Report,” included at the end of this chapter.

Required Tools and

Supplies

In addition to a standard set of hand tools, you will need the items listed below.

Table 3-1. Tools and Supplies

Item Part Number

#10 TORX driver

Leakage current tester MT-1216-02AAMI (for 220V)

MT-1216-01AAMI (for 110V)

Multifunction micro-simulator MARQ 1

Precision dust remover

Lint-free soft cloth TX609

Revision B 3-3

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Maintenance: Inspection and Cleaning

Inspection and Cleaning

Visual Inspection

Exterior Cleaning

Perform a visual inspection of all equipment and peripheral devices daily. Turn off the unit and remove power before making an inspection or cleaning the unit.

■ Check the case and display screen for cracks or other damage.

■ Regularly inspect all cords and cables for fraying or other

damage.

■ Verify that all cords and connectors are securely seated.

■ Inspect keys and controls for proper operation.

◆ Toggle keys should not stick in one position.

◆ Knobs should rotate fully in both directions.

Clean the exterior surfaces monthly, or more frequently if needed.

1. Use a clean, soft cloth and a mild dishwashing detergent diluted in water.

2. Wring the excess water from the cloth. Do not drip water or any liquid on the equipment, and avoid contact with open vents, plugs, or connectors.

3. Dry the surfaces with a clean cloth or paper towel.

Interior Cleaning

General

Check for dust buildup on the surfaces of the interior circuit boards, components, and power supply. Use commercially available compressed air to blow away the accumulated dust. Follow the manufacturers directions.

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Revision B3-4

Maintenance: Inspection and Cleaning

Thermal Printhead

Clean the thermal printhead every three months or more often with heavy use. A build-up of thermal paper coating on the printhead can cause light or uneven printing.

Use a solution containing alcohol on a nonwoven, nonabrasive cloth such as Techni-Cloth to wipe off the printhead. Do not use paper toweling, as it can scratch the printhead.

Thermal Printhead

MD1322-004A

Revision B 3-5

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Maintenance: Battery and Patient Cable Replacement

Battery and Patient Cable Replacement

Battery Replacement

Patient Cable

Replacement

1. Press the internal access button to open the unit.

2. Slide the battery release button in the direction of the arrow and lift the battery out.

MD1325- 112B

3. Install a new battery and close the unit.

1. Press the internal access button to open the unit.

2. Press connector release tabs and pull the connector loose.

3. Pull the cable from the retaining tabs.

4. Reassemble the cable by reversing the above steps.

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MD1322-006

Revision B3-6

Disassembly Guidelines

Maintenance: Disassembly Guidelines

Preliminary Steps

Power Supply

Removal

Prior to disassembly, perform the following:

■ If possible, process any ECGs remaining in storage.

■ If possible, print out set-up for future reference.

■ Disconnect the unit from the AC wall outlet and remove the

power cord from the unit.

■ Remove the battery.

■ Remove the chart paper.

■ Take strict precautions against electrostatic discharge damage.

NOTE

A #10 TORX driver is required for disassembly and assembly.

1. Turn the unit over so the bottom side is up.

2. Using a #10 TORX driver, remove the three screws holding the power supply in place.

3. Lift the power supply to expose the wiring harness and ground wire.

4. Remove P2 from J2 on the power supply assembly and the ground wire connection from the power supply chassis.

Three Screws

Ground Wire

Wiring Harness

MD1322 -001

Revision B 3-7

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Maintenance: Disassembly Guidelines

Reassembly

Top Cover

Removal

Reassemble the power supply reversing the steps for removal. Before replacing the screws, ensure that the ground wire is routed through the notch in the plastic and not pinched.

NOTE

It is not necessary to remove the power supply prior to removing the top cover.

1. Turn the unit over so the bottom side is up and remove the TORX screw through the hole on the right rear corner of the unit. (This screw is only visible and accessible with the battery removed.)

TORX Screw

MD1322-002

2. Turn the unit right side up and press the internal access button and raise the top of the unit.

3. Remove three TORX screws.

Three TORX Screws

MD1322 -004A

4. Lower the top of the unit and lock in place.

5. Raise the display to the vertical position.

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Maintenance: Disassembly Guidelines

6. Gently lift the rear of the top cover free from the unit.

NOTE

The top cover holds the bezel that surrounds the rear panel connectors, so the bezel may fall free at this time.

7. At the front of the top cover, gently pull the thin strip of plastic free from under the keyboard. The entire top assembly is now loose.

NOTE

It may be helpful to rotate the top cover 45 degrees to provide a larger opening t o clear the display.

8. Carefully lift the top assembly up and clear of the raised display.

Reassembly

Display/Keyboard

Assembly

Removal

1. Raise the display to the vertical position.

2. Make sure the bezel surrounding the rear panel connectors is in place. Make sure the release mechanism for the Smartmedia card functions properly.

3. Lower the top cover down around the display and set in position.

4. Snap the rear of the top cover in place and then, gently pulling on the thin plastic strip at the front of the top cover, position it in place under the keyboard assembly.

5. Replace the screws removed in disassembly.

1. Remove the top cover following the procedures above.

2. Label the three cables connecting the display/keyboard assembly to the main PCB. Disconnect these cables from the main PCB.

NOTE

Two of these cables have locked connectors that must be lifted up to release the cables.

Revision B 3-9

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Maintenance: Disassembly Guidelines

3. Press the internal access button and raise the top of the unit. Remove one screw on the inside, near the front edge of the top.

Screw

MD1322-004B

4. Working from the outside of the top, remove the two TORX mounting screws located on the right side of the assembly.

5. Slide the display hinge (metal rod) to the left to release it from the mounting detent.

Tabs

Hinge

Two TORX Mounting Screws

MD1322-005

6. Slightly lift up on the right hand side of the display/keyboard assembly, and pull the assembly to the right to free the tabs from their mounting slots. Do not lift the right side of the display too high or the plastic tabs may be damaged.

7. When free from the main unit, the display/keyboard assembly can be separated in to two pieces allowing replacement of either the keyboard or display assembly.

NOTE

Further disassembly of the LCD as sembly is not recommended. Replace as a complete assembly.

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Maintenance: Disassembly Guidelines

Reassembly

Main PCB

Removal

1. Slide tabs into their mounting slots and set the display/ keyboard assembly in place.

2. Replace the two TORX mounting screws on the right side of assembly.

3. Slide the display hinge (metal rod) to the right until it snaps into the mounting detent.

4. Connect the three cables from the display/keyboard assembly to the main PCB. Be sure to lift the locks up prior to attempting to insert the cables into the connectors.

1. Remove the top cover and display/keyboard assemblies following the procedures above.

2. Disconnect all remaining cable connections to the main PCB. These include cables to the

◆ power supply

◆ printhead

◆ battery connect PCB

◆ diskette drive

Reassembly

Printhead Replacement

Removal

Reassembly

3. Remove the mounting screws holding the main PCB in place. They are located around the outside edges of the main PCB.

4. Lift the main PCB from the unit.

1. Reassemble the main PCB reversing the steps for removal.

2. Install the battery and paper, then power on the unit and verify that the

◆ serial number and printhead resistance (label on printhead)

is correct

◆ setup parameters meet user’s requirements.

1. Remove the top cover and display/keyboard assemblies following the procedures above.

2. Using a Phillips head screw driver, remove the two screws that hold the printhead to the metal roller assembly.

3. Open the writer assembly, disconnect and remove the printhead.

1. Record the resistance value of the new printhead.

2. Connect the new printhead to the ribbon cable.

3. Hold the new printhead FIRMLY in place against the two metal tabs on the roller assembly, then tighten the two screws.

Revision B 3-11

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Maintenance: Disassembly Guidelines

4. replace the top cover and power up the unit.

5. Go to the Setup menu and enter the new printhead resistance value.

6. Do a Writer Daignostics test (See 4-19).

Diskette Drive Removal/

Replacement

Writer Roller/Carriage

1. Remove the top cover and display/keyboard assembly following the procedures above.

2. Remove the cable from the diskette drive to the main PCB.

3. Remove two screws holding the diskette drive in place. Loosen, but do not remove two TORX mounting screws holding the mounting bracket.

4. Detach the diskette drive and lift from the unit.

5. Apply the adhesive pad to the replacement diskette drive and position the drive in the unit. Insert and loosely attach the two screws.

6. The mounting screws MUST be tightened in the following order:

◆ Tighten the two TORX mounting screws,

◆ then tighten the two screws holding the drive to the

mounting bracket.

7. Connect cable to the main PCB.

8. Replace the display/keyboard assembly and the top cover following procedures above.

Assembly

Removal

Reassembly

1. Remove the power supply assembly following procedures above.

2. Inside the power supply compartment, disconnect the cable that connects to the writer assembly.

3. Open the unit to access the paper compartment. Move the paper size bracket to the A4 position to expose one of the writer assembly mounting screws.

4. Remove the screw and return the paper size bracket to the

8.5 x 11 position.

5. Close the unit and turn it over so the bottom side is up.

6. Remove the four screws located on the underside of the writer roller/carriage assembly and lift the writer from the bottom of the unit.

Reassemble the writer roller/carriage assembly by reversing the above procedures.

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Domestic Electrical Safety Tests

Maintenance: Domestic Electrical Safety Tests

AC Line Voltage Test

120 VAC, 50/60 Hz

This test verifies that the domestic wall outlet supplying power to the equipment is properly wired. For international wiring tests, refer to the internal standards agencies of that particular country.

Use a digital voltmeter to check the voltages of the 120-volt AC wall outlet (dedicated circuit recommended). If the measurements are significantly out of range, have a qualified electrician repair the outlet. The voltage measurements should be as follows:

1. 120 VAC (± 10 VAC) between the line contact and neutral and between the line contact and ground.

2. Less than 3 VAC between neutral and ground.

NEUTRAL

❶

LINE

❶❷

GROUND

MD1128-011A

240 VAC, 50/60 Hz

Use a digital voltmeter, set to measure at least 300 VAC, to check the voltages of the NEMA 6-20R, AC wall outlet (dedicated circuit recommended). If the measurements are significantly out of range, have a qualified electrician repair the outlet. The voltage measurements should be as follows:

1. 120 VAC (± 10 VAC) between either “hot” contact and ground.

2. 210 to 230 VAC between the two “hot” contacts.

HOT

❶

❷

❶

GROUND

HOT

MD1128-012A

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Maintenance: Domestic Electrical Safety Tests

Leakage Tests

The leakage tests are safety tests to ensure that the equipment poses no electrical health hazards. Use the table below to determine which tests apply to the unit under test and the maximum allowable leakage currents. For international leakage limits, refer to the internal standards agencies of that particular country.

If the unit under test fails the leakage tests, do not allow the customer to

use the equipment. Call Tech Support for assistance. (See the “How to Reach Us” page in the front of the manual.)

GE Marquette Medical Systems recommends that you perform these tests:

■ Before applying power for the first time

■ Every 6 months as part of routine maintenance

■ Whenever internal assemblies are serviced

NOTE

The accuracy of the leakage tests depend s on a properly-wired wall outlet. Do not proceed until you verify the integrity of the power source.

WARNING

Total system leakage current must not exceed 300 microamperes.

M15287-76A

Table 3-2. Leakage Tests and Maximum Allowable Leakage Currents

Test Maximum Current (µA)

1 Ground-wire-leakage-to-ground 300

2 Chassis-leakage-to-ground 300

3 Patient-cable-leakage-to-ground 10

4 Patient-cable-leakage-into-patient-leads-from-120 V ac 20

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Maintenance: Domestic Electrical Safety Tests

Leakage Test Diagrams

Test #1

Tester

power

Line

Neutral

Gnd

cord

These diagrams show only a representation of how a typical leakage current tester functions. Follow the instructions provided with the leakage current tester that you use.

Ground-wire-leakage-to-ground

“To be tested” power connector on back of tester (may not be labeled on some testers).

Tester

connectors

Meter

Polarity

Norm

Rvs

Neutral

Line

Gnd

UUT

power

cord

Unit

under

test

(UUT)

M13052-01E

Line

Neutral

Gnd

Test #2

Tester power

cord

Chassis-leakage-to-ground

Apply line voltage to the UUT chassis for this test.

“To be tested” power connector on back of tester (may not be labeled on some testers).

Tester

Meter

connectors

Polarity

Norm

Rvs

Neutral

Line

Gnd

UUT

power

cord

Probe to exposed chassis

Unit

under

test

(UUT)

M13052-02E

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Maintenance: Domestic Electrical Safety Tests

Line

Neutral

Gnd

Test #3

Tester power

cord

Test #4

Patient-cable-leakage-to-ground

“To be tested” power connector on back of tester (may not be labeled on some testers).

Tester

connectors

Meter

Polarity

Norm

Rvs

Line

Neutral

Gnd

Patient

cable connectors

UUT

power

cord

Patient cable

Unit

under

test

(UUT)

Patient-cable-leakage-into-patient Leads-from 120 VAC

During this test, line voltage is applied to the patient cable connectors. To prevent erroneous readings, do not allow the leadwires to contact conductive materials such as metal handles, and do not place the leadwires on the floor.

M13052-03E

Line

Neutral

Gnd

Tester

power

cord

Tester

Meter

connectors

Polarity

Norm

Rvs

Line

Neutral

Gnd

Patient

cable connectors

“To be tested” power connector on back of tester (may not be labeled on some testers).

UUT

power

cord

Unit

under

test

(UUT)

Patient cable

M13052-04E

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Revision B3-16

Maintenance: Domestic Electrical Safety Tests

Ground Continuity

This test verifies that there is continuity (less than 100 mΩ resistance) between all the exposed metal surfaces, which have the potential to become energized, and the ground prong on the mains AC power cord. If the metal surfaces are anodized or painted, scrape off a small area in an inconspicuous area for the probe to make contact with the metal.

■ Use a digital multimeter to check ground continuity from the AC

line cord ground pin to exposed metal surfaces. (i.e. rear panel ground lug, ANA/TTL, and EXT. VID. )

■ If the measurements are significantly out of range, check for

breaks in the power cord or in the internal connections within the unit.

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Maintenance: Preventive Maintenance

Preventive Maintenance

GE Marquette Medical Systems recommends that every six months you perform the maintenance checks and test procedures on the

“Preventive Maintenance Inspection Report”. These maintenance procedures can be performed more often if indicated. Contact GE Marquette Service for the latest preventive maintenance procedures for this product.

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4 Troubleshooting

Assembly Descriptions .................................................................. 3

Introduction ........................................................................................... 3

Assembly Block Diagram ....................................................................... 3

Input and Output Connectors ........................................................... 4

A Pins (J1) ............................................................................................. 4

COM1 (COM3/4) Pins (J3) ..................................................................... 4

COM2 Pins (J5) ..................................................................................... 4

ANALOG Pins (J6) ................................................................................. 5

EXT. VID. Pins (J7) ................................................................................ 5

Internal Cabling ......................................................................... 6

CPU PCB Input/Output Signals ......................................................... 8

Battery Pack/Monitor (J2) ...................................................................... 8

LCD Backlight (J4) ................................................................................. 8

Keyboard (J8) ........................................................................................ 9

LCD (J10) ............................................................................................ 10

Power Supply/Motor (J11) .................................................................. 11

Thermal Printer (J12) .......................................................................... 12

Floppy Disk Drive (J13) ....................................................................... 13

Acquisition Module (J14) ..................................................................... 13

Revision B

General Fault Isolation ............................................................... 14

Visual Inspection ................................................................................. 14

Power-up Self-test ............................................................................... 14

Power-up Flow Chart ........................................................................... 15

Poor Quality ECGs ................................................................................ 15

Diagnostic Tests ....................................................................... 16

Introduction ......................................................................................... 16

Loading the System Diagnostics .......................................................... 16

System Diagnostics Main Menu ........................................................... 17

Display Diagnostics ............................................................................. 17

Pixel Verification Test .............................................................17

Grey Scale Test Patterns ........................................................17

Anti-Aliasing Test Pattern .......................................................17

Speaker Test ........................................................................................ 17

Keyboard Diagnostics .......................................................................... 18

Writer Diagnostics ............................................................................... 19

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4-1

50 mm/sec Test Pattern I

25 mm/sec Test Pattern I

5 mm/sec Test Pattern I .........................................................19

Roller Test ..............................................................................20

Test Pattern II & Roller Test ...................................................20

Continuously Run Out Paper ..................................................20

Communication Diagnostics ................................................................ 21

4-2

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Revision B

Assembly Descriptions

Troubleshooting: Assembly Descriptions

Introduction

Assembly Block Diagram

The troubleshooting information in this chapter helps you narrow service problems to one of the replaceable assemblies. These assemblies, illustrated in the block diagram, are discussed in more detail in the individual assembly chapters along with replacement procedures.

Isolation Barrier

Patient

Acquisition

Module

Display

A (PS2)

Backlight

Keyboard

Floppy

CPU Board

ROM

Analog I/O

com1 com2

Video Out

Power Supply

Equipotential

AC inlet

Battery Pack

Speaker

Writer Thermal Printhead Motor

Cue Sensor

MD1322-014

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Troubleshooting: Input and Output Connectors

Input and Output Connectors

The pin-by-pin descriptions identify the signal names and pin outs for each connector on the unit.

A Pins (J1)

COM1 (COM3/4) Pins

(J3)

Table 4-1. A (J1)

Pin Name

1Data 2 NC 3 Ground 4 +5V 5Clock 6 NC

Table 4-2. COM1 (J3)

Pin COM1 Signal COM3/4 Signal

1 RTS COM3 TxD 2 CTS COM3 RxD 3TxD 4 Ground 5RxD 6 DTR COM4 TxD 7 +12V 8 DSR COM4 RxD

MD1322 -008

MD1322 -007

COM2 Pins (J5)

Table 4-3. COM2 (J5)

Pin Name

1RTS 2 CTS 3TxD 4 Ground 5RxD 6 DTR 7+12V 8 DSR

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MD1322 -007

Revision B4-4

Troubleshooting: Input and Output Connectors

ANALOG Pins (J6)

EXT. VID. Pins (J7)

Table 4-4. Acquisition Module Connector (J4)

Pin Name

1+12V 2 DC Output 1 3 TTL Trigger Output 4 Ground 5 Ground 6 DC Output 2 7 DC Input 1 8 ECG Output

9 DC Input 2

Table 4-5. External VGA Video (J7)

Pin Name

1Red Video 2 Green Video 3Blue Video 4 Ground 5 Ground 6 Ground 7 Ground 8 Ground

9NC 10 Ground 11 Ground 12 NC 13 Horizontal Sync 14 Vertical Sync 15 NC

MD1322 -010

MD1322 -009

Revision B 4-5

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Troubleshooting: Internal Cabling

Internal Cabling

Power Supply

421117-001

A9J1

A9J2

A11P2 P1

This diagram shows the cables and connectors for the assemblies in the unit. The following pages detail the input/output signals for those connectors.

W3P1

Power

Input

W1E1

E1 Power Supply Mounting Bracket

W1E3

A9 - Power Supply

A11P3

A10J1

A10

Led BD

801222-001

700645-001

A11

Motor

P1 J2

Motor BD

801600-001

A7 - Writer Assembly

A11P1

E4 E5

A8P3 A8P2

422397-001

700682-001

Printhead

Sensor

A6P2

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MD1322-015L

Revision B4-6

EXTVIDEO

ANALOG

COM

COM1

Troubleshooting: Internal Cabling

MISC

700687-001

Nand

Card

A8P1

A1PWRMTR

A6P1

A1TPH

CPU Board

801212-001

A1KEYBD

A5P1

A12

Floppy Drive

A5J1

Keyboard Assy

421115-001

RIBBON

FLOPPY

ACQ

A3P1

A1BATTRY

A12

Floppy Drive

419751-001

A2J1

A1LGHT

A2J2

A1LCD

700657-001

CAM-14

900995-001

Battery

A3J2

801220-001

A3J1

A4P1

Battery Pack

900770-001

LCD Assy

421114-001

MD1322-016R

Revision B 4-7

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Troubleshooting: CPU PCB Input/Output Signals

CPU PCB Input/Output Signals

Battery Pack/Monitor

(J2)

LCD Backlight (J4)

Pin No. Signal

1 18V Battery Power 2 18V Battery Power 3 Battery Temperature Sense 4 3V Temperature Sense Power 5 Battery Ground 6 Battery Ground

Pin No. Signal

1 12V Power 2 12V Power 3 12V Power 4 Ground 5 Ground 6 Brightness Select 7 Backlight Enable 8NC 9 Ground

10 Ground

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Revision B4-8

Keyboard (J8)

Troubleshooting: CPU PCB Input/Output Signals

Pin No. Signal

1 NC 2NC 3 NC 4NC 5 NC 6Sense4 7 Sense2 8Sense1

9 Sense0 10 Sense3 11 Sense5 12 Sense6 13 Sense7 14 Drive0 15 Drive1 16 Drive2 17 Drive3 18 Drive4 19 Ground 20 Power Key 21 Drive5 22 Drive6 23 Drive7 24 Drive8 25 Drive9 26 Drive10

Revision B 4-9

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Troubleshooting: CPU PCB Input/Output Signals

LCD (J10)

Pin No. Signal

1 Ground

2Pixel Clock

3 Hsync

4Vsync

5 Ground

6 R0 (LSB)

7 R1

8R2

9 R3 10 R4 11 R5 (MSB) 12 Ground 13 G0 (LSB) 14 G1 15 G2 16 G3 17 G4 18 G5 (MSB) 19 Ground 20 B0 (LSB) 21 B1 22 B2 23 B3 24 B4 25 B5 (MSB) 26 Ground 27 Data Enable 28 3V Power 29 3V Power 30 NC 31 NC

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Revision B4-10

Troubleshooting: CPU PCB Input/Output Signals

Power Supply/Motor

(J11)

Pin No. Signal

1 Motor Encoder B

2 5V Power

3 Motor A

4 Motor Encoder A

5 Ground

6Motor B

7 NC

8 28V Power

9 Ground 10 Battery Charge LED 11 28V Power 12 Ground 13 Door Open Detect 14 Ground

Revision B 4-11

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Troubleshooting: CPU PCB Input/Output Signals

Thermal Printer (J12)

Pin No. Signal

1 Thermal Printer Power

2 Thermal Printer Power

3 Thermal Printer Power

4 Thermal Printer Power

5 Thermal Printer Power

6 Thermal Printer Power

7 Thermal Printer Power

8 Ground

9 Ground 10 Ground 11 Ground 12 Ground 13 Ground 14 Ground 15 Cue Sense 16 NC 17 5V Main Power 18 Ground 19 Data Strobe 20 Data Strobe 21 Data Strobe 22 Data Strobe 23 Data Load 24 Data Clock 25 Print Head Temperature 26 Pixel Data

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Revision B4-12

Floppy Disk Drive (J13)

Troubleshooting: CPU PCB Input/Output Signals

Pin No. Signal

1 5V Power

2Index

3 5V Power

4 Drive Select 0

5 5V Power

6 Disk Change

7 NC

8Media Sense 0

9 Media Sense 1 10 Motor Select 0 11 NC 12 Direction 13 NC 14 Step 15 Ground 16 Write Data 17 Ground 18 Write Gate 19 Ground 20 Track 0 21 Ground 22 Write Protect 23 Ground 24 Read Data 25 Ground 26 Head Select

Acquisition Module (J14)

Pin No. Signal

1 Power

2 Ground

3 TX+ (RS485)

4 TX- (RS485)

5 RX+ (RS485)

6 RX- (RS485)

7 NC

8NC

9 NC 10 NC

Revision B 4-13

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Troubleshooting: General Fault Isolation

General Fault Isolation

Visual Inspection

A thorough visual inspection of the equipment can save time. Small

things—disconnected cables, foreign debris on circuit boards, missing hardware, loose components—can frequently cause symptoms and equipment failures that may appear to be unrelated and difficult to track.

Take the time to make all the recommended visual checks before starting any detailed troubleshooting procedures

Table 4-6. Visual Inspection List

Area Look for the following problems

I/O Connectors and Cables

■ Fraying or other damage

■ Bent prongs or pins

■ Cracked housing

■ Loose screws in plugs

Fuses ■ Type and rating. Replace as necessary.

Interface Cables

■ Excessive tension or wear

■ Loose connection

■ Strain reliefs out of place

Circuit Boards ■ Moisture, dust, or debris (top and bottom)

■ Loose or missing components

■ Burn damage or smell of over-heated components

■ Socketed components not firmly seated

■ PCB not seated properly in edge connectors

■ Solder problems: cracks, splashes on board, incomplete feedthrough, prior modifications

or repairs

Ground Wires/Wiring

■ Loose wires or ground strap connections

■ Faulty wiring

■ Wires pinched or in vulnerable position

Mounting Hardware ■ Loose or missing screws or other hardware, especially fasteners used as connections to

ground panes on PCBs

Power Source

■ Faulty wiring, especially AC outlet

■ Circuit not dedicated to system

(Power source problems can cause static discharge, resetting problems, and noise.)

Power-up Self-test

On power-up, the system automatically runs an internal self-test. If all circuits test good, the start up screen displays.

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Troubleshooting: General Fault Isolation

Power-up Flow Chart

Press ON key

Sh4

3VC

Micro-Controller

* Reset

"MOE"

Sh8 pin 5

AC Present? Sh8

pin 13

Battery OK? Sh8

pin 17

Refer to the CPU PCB schematic diagram found in the PCB Assemblies chapter at the end of the manual.

StrongArm

access

SmartMedia card

via FPGA and

loads remaining

code to DRAM

StrongArm

running?

Yes

Run application

software

Yes

"MOE" releases

nSysResest

Sh8 pin 10

Micro-Controller

"CURLY"

Sh2

configures FPGA

Sh2

"CURLY" reads

SmartMedia card

and moves

instruction byte

to FPGA for "unpacking"

Yes

"MOE" enables

+3VM and +5VM

Stabilization period

over?

Poor Quality ECGs

Start-up screen

displayed

Yes

four bytes loaded

to FPGA?

Yes

"CURLY" asserts

WordRdy Sh2 pin 9

FPGA puts

unpacked instruction

on StrongARM

data bus and

negates nWait

Poor quality ECGs can be caused by factors in the environment, inadequate patient preparation, hardware failures related to the acquisition module, leadwires, cables, or problems in the unit.

MD1322-017A

Use a simulator to obtain an ECG report. If the report is good, the problem is external to the unit.

Revision B 4-15

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Troubleshooting: Diagnostic Tests

Diagnostic Tests

Introduction

Loading the System

Diagnostics

Verify that the MAC 5000 resting ECG analysis system operates properly by running the diagnostic tests. These tests check the operation of the display screen, speaker, keyboard, thermal writer, battery, and communication. Detailed information displays on screen.

1. Select Main Menu on the Resting screen.

2. Select More.

3. Select System Setup.

4. At the prompt type the word “system”, the password set at the

factory, then press the enter key. If the password was not changed, the System Setup menu appears. If the menu does not appear, use the master password. If the system’s unique password is inaccessible, create one following the instructions in “Substitute Master Password” later in this section.

5. When the System Setup menu displays, hold down shift and

press F5 (shift + F5).

6. Type “prod” at the service password prompt.

7. The System Diagnostics menu appears.

Substitute Master Password

If you do not have access to the system’s password, you can create a master password as follows.

1. At the prompt for the system password, enter meimac. A

random 6-digit number displays on the screen. For example,

876743.

2. Write the number down and create a new 6-digit number by adding alternating digits from the random number as follows. Add:

◆ first and third digits,

◆ second and fourth digits,

◆ third and fifth digits,

◆ fourth and sixth digits,

◆ fifth and first digits, and

◆ sixth and second digits.

Disregard the 10s column when adding the digits. The new number from the example above would be 440020.

3. Enter the new number, then press the enter key. The System Setup menu displays.

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This process only works once, so you should reprogram the password permanently.

4. Go to the Basic System menu.

5. Select Miscellaneous Setup.

6. Select the System password line and type the new password in the space.

7. Press the enter key.

8. Select Save Setup from the System Setup menu.

9. Select To system.

System Diagnostics

Main Menu

Display Tests

Use the arrow pad control to highlight a menu item, then press the enter key to select it. The tests and test menus contain on-line prompts and/ or instructions.

■ Display Tests

■ Speaker Test

■ Keyboard Test

■ Writer Tests

■ Battery Tests

■ Communication Tests

■ Acq. Module Tests

■ Analog I/O Tests

■ Floppy Drive Tests

■ Exit System Diagnostics (reboots the system)

Run the screen display tests to verify that all the screen pixels are working and that the brightness and contrast samples appear to be within normal range. There are no screen display adjustments. The screen display tests are as follows.

Pixel Verification Test

Grey Scale Test Patterns

Revision B 4-17

Use the arrow pad control to move the bar across the screen and look for any missing pixels on the display.

Press the F1 key to turn on all of the pixels simultaneously. Leave the

screen in this test mode over night to remove the “burned-in” look to the softkeys.

Press the enter key to exit the test.

The first test pattern (used in manufacturing to verify the screen intensity) shows two squares, one bright and one dim. Press any key to activate the next display.

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The second test pattern shows 32 color levels. Check for problems with the overall pattern. (If the system does not have the color option, various grey scale patterns display.)

Press the enter key to exit the test.

Anti-Aliasing Test Pattern

Speaker Test

Keyboard Test

This test pattern consists of a large square with a series of lines projecting from the center of the square to the perimeter of the square. Specifications not currently defined.

Press the enter key to exit the test. Highlight Return and press the enter key to return to the System Diagnostics menu.

Use the arrow pad to select Loud or Soft. Press the enter key to produce a loud or soft tone. (The tone level difference is minimal.)

Highlight Return and press the enter key to return to the System Diagnostics menu.

Press each key and verify that the key is highlighted on the screen and also displayed at the top of the screen. (It is normal for a dim background image to remain on the screen when you select the next key.) The numeric value that displays at the top of the screen is the scan code representation of the pressed key.

NOTE

The display shows keys in the upper part of the screen that are not presently available on the keyboard.

■ Check both of the shift keys by pressing each in combination

with a letter to display a capital letter.

■ Press the center of arrow pad control and verify that the word IN

displays on screen. Press arrows to change the displayed arrow position. A beep sounds with each arrow press.

■ Press the shift key and the F6 key to exit the test.

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Writer Tests

C-Scan Test 1 C-Scan Test 2 C-Scan Test 3

50 mm/s Test Pattern I 25 mm/s Test Pattern I

5 mm/s Test Pattern I

Run the writer tests to check the motor speed control, paper speed, paper tracking, paper cueing, and print head quality. During the tests, make the following general checks.

■ The first character printed should not be distorted. This checks

start-up speed.

■ The writer should not skew or crush either edge of the paper.

■ The large triangles and diagonal lines printed across the pages

should be straight and uniform, without curves or wavering.

■ The perfs should align with the tear bar on the door after cueing.

■ Paper travel should be smooth.

These tests are combinations of test pattern I and the roller test. They are used by the vendor.

These test patterns check the motor speed control and the paper speed.

Verify that the length of the printout from start to finish is 250 mm ± 5 mm. Use the grids located on the top and bottom of the page for reference. Do this for each of the three tests.

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Roller Test

(Uneven darkness can appear if AC power is on during this test.)

■ After cueing, printing should start at approximately 13–14 mm

on the page.

■ The pattern appears as diagonal light and dark wavy bands.

Test Pattern II

Test Pattern II Continuous

Continuously Run Out Paper

Battery Tests

Battery Statu

◆ Isolated light spots indicate a flat spot on the roller.

◆ A white line across the length of the page indicates a missing

print head dot.

◆ Dark lines across the width of the page indicate gear

tolerance problems.

◆ Lines too close together at the start of the test indicate an

incorrect start-up speed.

A combination of Test Pattern I and Roller tests. The first three pages consist of a series of triangular waveforms and various hashmarks. The fourth page is a partial roller test.

Test Pattern II runs continuously until stop is pressed.

This test is used in manufacturing to test how well the unit self-corrects tracking problems.

Displays, and constantly updates, the following information:

MD1322-013

■ Percent of charge remaining

■ Battery voltage

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■ Battery current

■ Battery temperature

■ Maximum and minimum battery temperature

■ Ambient temperature

■ Maximum and minimum ambient temperature

■ Current battery charging status

Battery Discharge Test

Battery Charge Test

Print Discharge Test Results

Print Charge Test Results

This test charges the battery to full capacity, if necessary, then monitors a discharge cycle. Monitored information, written to the floppy disk, includes:

■ Discharge rate (in mAH)

■ Battery temperature

■ Battery charge status

■ Percent of charge remaining

This test completely discharges the battery, if necessary, then monitors a charge cycle. Monitored information, written to the floppy disk, includes:

■ Charge rate (in mAH)

■ Battery temperature

■ Battery charge status

■ Percent of charge

Writes the results of the last discharge or charge test to a floppy disk for later printing to the writer.

Communication Tests

COM Port Loopback Test

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The Communications Port Loopback Test sends various ASCII characters

out the COM port’s transmit lines and expects the same character to return in it’s receive lines.

1. Select COM 1: Base System and press the enter key.

2. Follow the instructions on screen and install loopback jumpers in the COM 1 port. (Make note of these jumpers as they are the same for COM 2 Modem Option test.)

While the test is in process, the word Testing appears in the upper right corner of the screen. Upon completion, the word Passed or Failed appears, depending on the results.

3. Remove the loopback jumpers when the test is complete.

Follow the same steps for the COM 2 Modem Option test.

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Modem Test

Acq. Module Tests

Analog I/O Tests

Analog Output Test

Connect a modem to COM 2 and select the test. The test returns the modem ID number, firmware rev, and current parameter settings. If communication with the modem is unsuccessful, the ID and firmware rev display N/A.

Follow the instructions on screen.

■ Tests if the front end is powered

■ Tests if the front end is communicating

■ Displays the front end noise floor

■ Indicates when one of the three front end buttons is pressed

Follow the instructions on screen to monitor the analog outputs using an oscilloscope. The outputs monitored are:

◆ +12V

◆ DC Output 1

Analog Input Test

DCOut Loopback Test

ECGOut/QRSTrigger Loopback

Test

◆ DC Output 2

◆ ECG Output

◆ TTL Trigger Output

Four sets of outputs are possible. Select the output sets using the arrow pad.

Follow the instructions on screen to connect a DC voltage to the DC input pins of the ANA/TTL connector. The voltage of the DC input displays.

Follow the instructions on screen to connect the DC Outputs to the DC Inputs. The test sends all possible values out the DC Outputs and confirms that the correct values are read from the DC Inputs. A pass/fail result displays.

Follow the instructions on screen to connect the ECG Output and TTL Trigger Output to the DC Inputs. The test sends all possible values out the ECG Output and a square wave out the TTL Trigger Output. It confirms that the correct values are read from the DC Inputs. A pass/fail result displays.

Floppy Drive Tests

Follow the instructions on screen. A read/write test is performed on a formatted floppy disk. A pass/fail test result displays.

A head radial alignment and Azimuth alignment test is performed using an Accurite test disk. Test values display.

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5 CPU Theory of Operation

General Description ..................................................................... 3

Block Diagram ....................................................................................... 4

Theory of Operation ..................................................................... 6

Clocks .................................................................................................... 6

CPU ........................................................................................................ 6

FPGA ...................................................................................................... 6

Bootstrap Instruction Unpacker ................................................7

EDO DRAM Controller ..............................................................7

XBus Controller ........................................................................ 7

LCD Controller VLB Bus Cycle Interface ...................................7

Video Waveform Scrolling ........................................................8

Interrupt Controller ...................................................................9

System Interrupt Generator ......................................................9

Acquisition Module Interface ....................................................9

Thermal Printhead Interface ...................................................10

Serial EEPROM Interface ........................................................10

BBus Interface ........................................................................10

UARTS ....................................................................................11

PWM Analog Outputs .............................................................11

Beep Generator .......................................................................11

DRAM .................................................................................................. 12

SmartMedia Card ................................................................................. 12

Serial EEPROM .................................................................................... 12

VGA LCD/CRT Interface ....................................................................... 12

Acquisition Module Transceiver/Power Switch .................................... 12

Thermal Printhead Power/Pixel Test Logic .......................................... 12

SuperIO Peripheral Controller .............................................................. 13

Floppy Drive Support ..............................................................13

Four RS-232 Serial Ports (one dual mode RS-232/IrDA) .......13

Clock/Calendar ....................................................................... 13

External PS-2 Keyboard Port ..................................................13

General Purpose Parallel I/O Lines .........................................13

The Four Stooges ................................................................................. 13

Startup Self Identification .......................................................14

BBus .......................................................................................14

Curly .......................................................................................14

Shemp ....................................................................................14

Larry .......................................................................................15

Moe ........................................................................................15

Untested "Nominal" Operating Time Specs ........................................... 19

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General Description

CPU Theory of Operation: General Description

The MAC 5000 CPU PCB contains all of the circuitry for the MAC 5000 resting ECG analysis system except for the power supply, acquisition module, keyboard and display.

The board contains the following:

■ Clocks

■ StrongARM CPU (SA-110)

■ FPGA for System Logic Containing:

Bootstrap Instruction Unpacker EDO DRAM Controller XBus Controller LCD Controller VLB Bus Interface Video Waveform Scroller Interrupt Controller System Interrupt Generator Acquisition Module Interface Thermal Printhead Interface Serial EEPROM Interface BBus Interface Two UARTs Four PWM Analog Outputs Beep Generator Two Serial Ports

■ 4MBytes EDO DRAM (holds both code and data)

■ 2MBytes SmartMedia Flash (holds FPGA configuration and

system code)

■ VGA LCD Controller and CRT video DACs

■ Acquisition Module Transceiver/Power Switch

■ Thermal Printhead Power Switch and Pixel Test Circuit

■ A PC SuperIO controller containing:

Floppy Disc Drive Controller Two Serial Ports (one dual mode RS-232 / IrDA) Clock/Calendar (Y2K compliant even!) PS-2 Keyboard Port (for card and bar-code readers) General Purpose Parallel I/O Port for Miscellaneous Control

■ Four Stooges Controlled Resources:

Four Stooges Overview Bootstrap Control (Curly) Keyboard Interface (Shemp) Printer Motor Controller/Analog Input (Larry) Main Power Supplies/Battery Charger-Gauge (Moe)

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SA-110

TRONGARM

CPU

(Sh2)

Block Diagram

See Chapter 7, “PCB Assemblies” for references on the CPU schematic.

TRONGARM Address Bus

FPGA

DRAM

Controller

DRAM

Address

Mux

(Sh2)

Bootstrap

Unloader

RA0-9

BBUS

I/F

4 MEG

EDO

DRAM

Analog

(Sh2)

Audio

VGA LCD

Controller

(Sh2)

A0-8

Memory

MAD0-15

TRONGARM Data Bus

(Sh3)

Acq Module

I/F

TPH I/F

EEPROM I/F

VLB Bus I/F

XBus

Controller

"Curly"

68HC705

(Sh2)

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To Super I/O

D/A

(Sh7)

Speaker

Driver

(Sh7)

MNX490

(Sh5)

Controllers

68HC705

"Larry"

(Sh6)

"Shemp"

(Sh4)

Sh6

Drive

Sense

Motor

Keyboard

Top Up

"Moe"

System

Supervisor

(Sh8)

Power Suppy Enable On/Off Key System Reset AC Power Ambient T emper ature Change Control Battery E Sense Battery I Sense Battery T emperature

Analog I/O

16K

AM-110/114

Serial/Memory

(Sh4)

Sh3

QP4,5,6

(Sh3)

X Bus

SmartMedia

Card

(Sh2)

Printhead

LCD

Remote

Video

From

TRONGARM Address Bus

CPU/IDE

FDC

COM 1

COM 2

GP I/O

RTC

Super I/O

Peripheral Controller

TX,RX

Floppy

Drive

MAX213

(Sh4)

MAX213

(Sh4)

COM

MD1322-011R

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Theory of Operation

Clocks

CPU

FPGA

The main system logic operates from one of three clocks, all derived from a single 24MHz oscillator. That 24MHz clock is used directly by the FPGA to control the timing of internal peripherals. It is also used as the reference frequency for the LCD controller PLL clock synthesizer (after division to 12MHz) and the PLL clock synthesizer in the StrongARM (after division to 4MHz). In addition, each of the four HC05 microcontrollers has its own 4MHz ceramic resonator.

The Intel StrongARM SA-110 CPU, chosen for its high performance, low power consumption and high code density, is at the heart of MAC 5000. The SA-110 is a bare processor with no integrated peripherals other than clock generation, MMU and L1 cache. The StrongARM core and bus clocks are generated internally from an external reference clock. The multiplying factors for each clock are set by strapping configuration pins. See theCPU schematic and StrongARM data sheet for the current CPU and bus speed settings (at the time of this writing, the CPU clock was 206MHz and the bus clock was 26MHz).

All of the MAC 5000’s proprietary hardware is contained in a single Xilinx FPGA which contains:

■ Bootstrap Instruction Unpacker

■ EDO DRAM Controller

■ XBus Controller

■ LCD Controller VLB Bus Interface

■ Video Waveform Scroller

■ Interrupt Controller

■ System Interrupt Generator

■ Acquisition Module Interface

■ Thermal Printhead Interface

■ Serial EEPROM Interface

■ BBus Interface

■ Two UARTs

■ Four PWMAnalog Outputs

■ Beep Generator

■ Two Serial Ports

The following descriptions give an overview of the FPGA’s functionality. For detailed information on the internal circuitry, refer to the schematic.

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Bootstrap Instruction Unpacker

EDO DRAM Controller

The FPGA provides an interface that unpacks instructions to start the CPU from the byte wide SmartMedia card. Early during system startup, Curly extracts instruction bytes from the card and presents them to the FPGA for unpacking. Each instruction byte is loaded into the FPGA via the signal ByteRdy. Curly asserts the SmartMedia nFRD signal while simultaneously asserting ByteRdy to improve transfer rate. Curly generally does not examine the instruction bytes (a more complete explanation of the bootstrap process is presented in Curly’s source code). When four bytes (one instruction) have been loaded into the FPGA, Curly asserts WordRdy and the FPGA places the unpacked instruction on the StrongARM data bus and negates nWait, allowing the StrongARM to fetch and execute the instruction. In this fashion the initial bootstrap loader is loaded into main DRAM. Curly’s read rate is far too low to load all code from the card, so only a simple bootstrap program is copied to DRAM. This program contains code that allows the StrongARM to access the SmartMedia card directly through the FPGA. Once that initial bootstrap is loaded, Curly disconnects from the circuit (tri states all pins except nReset) and stops its internal clock. StrongARM execution is transferred to the bootstrap loader in DRAM and the remaining system code is read from the card at high speed. The byte unpacker lies dormant until the next startup.

MAC 5000 main memory is comprised of 4MBytes (2 1M x 16 devices) of EDO DRAM. The FPGA provides a burst interface to DRAM that allows 8 word bursts at 4-1-1-1-1-1-1-1 clocks. Write bursts run at 4-2-2-2-2-2-22 clocks. Single read/write accesses take 5 clocks. Refresh cycles (5 clocks) are queued approximately every 10 microseconds for an overhead of 2 percent. The control of DRAM nCAS requires logic delays shorter than can be obtained in the FPGA. For this reason a 3.5ns PAL provides the final stage of nCAS control. Enabling signals are provided by the FPGA and the PAL anchors the final nCAS signals off the main bus clock (nMCLK).

XBus Controller

LCD Controller VLB Bus Cycle

Interface

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To reduce loading on the high speed processor address and data busses, a slow speed byte bus is provided for peripheral interface. The SuperIO controller and SmartMedia card are both located on this bus. XBus is decoupled from main bus traffic to reduce EMI. XBus data lines are only active when an XBus device is being accessed. Unlike the 3.3V only main data/address busses, XBus is compatible with both 5V and 3.3V logic. StrongARM address lines A8..11 are buffered by the FPGA for use by XBus devices. To reduce loading on A1..A3 which drive the DRAM burst addresses, the low order address byte is not used by XBus. Starting XBus addressing with A8 also produces SuperIO addresses which easily map to their standard PC equivalents (simply append 00 to a PC SuperIO address to get a MAC5000 SuperIO address).

The LCD controller expects VESA local bus signaling, not StrongARM bus signaling. The FPGA provides the necessary logic to interface the StrongARM nMReq/nWait interface to the LCD controller’s nCS/nRdy/ nRdyRtn interface. The LCD controller does not support burst accesses .

Note: No LCD controller bus timeout logic is provided, so accesses to unmapped regions of controller space will hang the system.

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Video Waveform Scrolling

There are numerous ways of achieving this effect, none of which is supported by standard LCD controllers. MAC 5000 achieves scrolling through FPGA hardware placed between the LCD controller output and the LCD panel input.

To achieve the scrolling effect it is necessary to maintain two virtual image planes, one atop the other. Static (stationary) objects are drawn in the static plane, which appears nearest the viewer and may be either opaque or transparent. Dynamic (scrolling) objects are drawn in the dynamic plane, which appears behind the static plane and is always opaque, though not necessarily visible. The appearance of motion is achieved by constantly changing the start point for display of the dynamic plane from one display frame to the next.

Since the LCD controller does not support multiple image planes, it is necessary to pack two planes of image data into a single frame buffer. On the software side (during drawing) this is done by bit masking operations that allow separate manipulation of two virtual pixels in each byte of frame buffer memory. Each 8-bit byte holds a pair of pixels, one from the static plane and one from the dynamic plane.

On the hardware side, part of each frame buffer byte (the static plane) is played directly into the LCD after suitable color mapping. The remainder of the frame buffer byte (the dynamic plane) is stored in a 1 line temporal buffer before being displayed. The amount of delay applied to the line buffer before merging it with the static image data determines it’s placement on the screen. By gradually changing the delay, the dynamic image can be made to scroll.

In MAC 5000, each byte of frame buffer data is divided into a 5-bit field for the static plane and a 3-bit field for the dynamic plane. This provides a palette of 2^3=8 colors for dynamic objects and (2^5)-1=31 colors for static objects (1 of the colors is transparent, leaving 31 real colors). In practice, to be able to "freeze" dynamic objects requires that the 8 dynamic colors be replicated in the static color map, so there are actually only 31-8=23 new colors available for static objects. The FPGA implements a writeable color lookup table (CLUT) to map the pixel values to sensible colors on the LCD. The CLUT provides 32 24-bit entries, providing access to the complete color space offered by the LCD panel.

LCD data is also fed to three external discrete 6-bit DACs to create video for an external CRT. The horizontal and vertical sync pulses from the LCD controller are combined to produce a composite sync signal which is added to the green video. The FPGA’s asymmetric output drive current (stronger pulldown than pullup) makes it difficult to source video DAC currents directly into a 75 to sink rather than source the video DAC currents, the video output is referenced to the 3.3V supply rail and then level shifted back down to ground by emitter followers. The DC level is restored by a second set of emitter follower clamps referenced to two diode drops above ground. By using dual transistor packs of the same type, temperature and process drift are minimized.

Ω video cable. To allow the FPGA

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Interrupt Controller

System Interrupt Generator

Acquisition Module Interface

The StrongARM supports two external interrupts, FIQ (Fast Interrupt Request) and IRQ (Interrupt ReQuest). The FPGA expands these inputs to service numerous sources of interrupts in the FPGA internal logic and SuperIO. Each interrupt source is routed to either the FIQ or IRQ pin and is provided with a writeable enable bit and a readable status bit. Note in particular that the FIQ status bits are masked by FIQ mask bits whereas IRQ status bits are not. This reflects the different needs of the FIQ and IRQ interrupt handlers.

A 1KHz timer generates system interrupts (which may be routed to FIQ or IRQ) once every millisecond. This interrupt provides the foundation for all operating system timers.

Acquisition module timing is synchronized to the system clock. Data is framed and checksummed. Commands may be sent without interrupting the data stream. The acquisition module supports three buttons whose state is communicated to the system in each ECG data packet.

A constant reference clock frequency of 1MHz must be provided to the acquisition module for generation of it’s internal sampling clocks. To eliminate the need for extra wires, command information is encoded on this reference clock by altering its duty cycle. The FPGA provides a serializer for the command bytes and clock generator/modulator to transmit both the clock and command bits from the serializer. The reference clock duty cycle is nominally 50%. By altering the duty cycle, the DC content of the clock may be changed. This change in DC level is detected by the acquisition module. The timing of these shifts in DC offset encode command data bits. A zero is encoded as a single shift in

duty cycle from 50% to 25% lasting 30µs, followed by a refractory period of 220µs. A one is encoded as a pair of 30µs periods of 25% duty cycle separated by 90µs, followed by a 90µs refractory period. In either case the transmission of a single bit takes 250µs. Only the falling edge of the clock signal is moved to alter the duty cycle. This leaves a pristine rising edge for the acquisition module to use as the reference for its PLL clock generator. A higher level protocol organizes commands as groups of 8 bits.

Data from the acquisition module is packed into 257 bit NRZ frames. The idle state of the receive line is high. The first bit of each packet is a zero and serves as the packet start bit. As with a UART, the start bit is discarded. The following 256 bits are received into a 16 word x 16 bit buffer for use by the StrongARM. The receive logic then looks for an idle period (analogous to a UART stop bit) of at least 128µs in length as an indicator that the link is again idle. Special marker words are inserted into the ECG data packet (words 5, 9 and 13) to guarantee there will never be a run of more than 80 bits of one's (or zeros), so there is no possibility of satisfying the idle period requirement in the middle of a data packet. Because the acquisition module clock is supplied by the FPGA, receive bit timing errors are limited to phase uncertainty. By searching for the beginning of the start bit in a fashion similar to that used by UARTs the phase uncertainty is eliminated and the remainder of the packet may be received without further synchronization. In practice, the FPGA uses every edge in the receive data stream to re-sync

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its bit sampling circuit. It is possible for the ECG data to be all zeros or ones, so runs of as many as 80 zeros or ones could occur before a marker word is encountered in the data stream (which contains at least one "1" and one "0" to break any runs in the data).

The acquisition module supports a special "code update" mode for rapid reprogramming of it’s on-board code memory. To increase the update speed, the acquisition module echoes each uploaded code byte with a single reply word rather than the usual 16 word data packet. The FPGA receive logic provides a special 1 word reception mode to accommodate this.

Thermal Printhead Interface

The StrongARM sends print data to the thermal print head through a buffered serial interface. The FPGA implements the data buffer, serializer, strobe/latch pulse generator and power switch gate drive pump. Special interlocks are implemented to prevent stuck strobe signals or printing when the battery voltage is critically low.

Each print line requires 1728 bits of data. To conserve FPGA resources, each line is divided into three chunks of 512 bits each, with one leftover chunk of 192 bits. The FPGA provides a single 16 word x 32 bit buffer (512 bits) to hold the print line data. After writing a chunk of data to the buffer, the StrongARM enables serialization of the data by reading one of two registers (to support the serialization of either a full 512 bit or partial 192 bit buffer). When the entire print line has been loaded, the StrongARM cues a print strobe by writing the required strobe width value to the strobe/latch pulse generator.

When the strobe register contains a non-zero value, the power switch gate pump produces a differential clock signal to drive an external diode voltage doubler. The output of the voltage doubler drives the gate of a power MOSFET which provides power to the print head.

A special test mode is provided to allow testing of the thermal print head. In test mode, print head power is disabled and the strobe signal is driven continuously. This allows individual print dots to be driven with a small test current. The resulting voltage drop may be measured to either determine the dot’s resistance or a least determine of the dot is open.

Serial EEPROM Interface

BBus Interface

A standard SPI interface is provided for connection to a serial EEPROM memory. The StrongARM exchanges a byte of data with the EEPROM by writing a value to the interface register. Data is clocked at 4MHz, quickly enough that no interrupt support is required. The StrongARM polls a ready bit to determine when the transfer is complete.

There are several I/O functions poorly suited to direct control by the StrongARM, whether for reasons of software complexity or power consumption. These I/O functions are provided by three 68HC705 microcontrollers placed strategically around the board (Moe, Larry and Shemp). Each of these three microcontrollers must communicate with the StrongARM. BBus is a simple 1-wire point-to-point interface designed specifically for this purpose. The FPGA provides a single BBus

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transceiver and a 3-way bi-directional multiplexer to attach to the three BBus microcontrollers. From the programmer’s standpoint, BBus operates like SPI, where each transaction exchanges a single byte between the host and peripheral.

UARTS

Two full duplex UARTs are provided for COM3 and COM4. Each has programmable bit rates, but no handshake lines are provided. The receiver is double buffered, the transmitter single buffered. To reduce cost and conserve panel space, the COM3 and COM4 signal lines are connected to the COM1 handshake lines, so COM1 handshake functionality must be sacrificed to use COM3 or COM4. The COM3 and COM4 TxD outputs may be tri-stated to allow the COM1 handshake output lines to operate normally.

The handshake lines are shared as follows:

■ COM3 TxD COM1 RTS

■ COM3 RxD COM1 CTS

■ COM4 TxD COM1 DTR

■ COM4 RxD COM1 DSR

The available bit rates are: 1200, 4800, 9600, 19.2K, 38.4K and 115.2Kbps. The only frame format supported is 8N1.

Interrupts for COM3,4 are shared on a single IRQ vector. Tx buffer ready, Tx buffer clear and Rx buffer full status bits are provided.

Note that when COM2 is in IrDA mode the COM2 handshake lines are not used and COM3 and COM4 may be used without loss of COM2 functionality.

PWM Analog Outputs

Beep Generator

Four PWM channels are provided for the generation of analog outputs. Three of the outputs are available on the Analog I/O connector, the fourth is available internally for future use. One of the PWM channels provides 12-bit resolution at 6KHz cycle rate, the other three provide 8bit resolution at 96KHz cycle rate. The StrongARM simply writes the desired value into a PWM data register and the output duty cycle changes on the next PWM cycle. External analog circuitry converts the PWM logic signals to smooth analog voltages. The 12-bit PWM channel is intended for ECG output and produces a swing of +10 to -10V. The two 8-bit channels provide a unipolar 10V output. Regardless of the resolution or swing range of each PWM channel, the FPGA treats the data value as a signed 16-bit number representing a voltage from +10V (0x7fff) to -10V(0x8000). Logic in each PWM channel ensures that the closest possible voltage is generated for each data value (ex. 0x8000 on an 8-bit channel produces zero volts output).

A simple tone generator with two volume levels provides the system beep tones. Frequencies of 250Hz, 500Hz and 1KHz are provided at both low and high volume. The logic level output signal drives a speaker through an open collector transistor driver.

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DRAM

SmartMedia Card

Serial EEPROM

VGA LCD/CRT Interface

Program code and working data is stored in a single 1MWord bank of 32-bit wide memory (4MBytes). EDO DRAM is used to achieve moderate burst rates (75MBytes/sec @ 26MHz bus speed). All bus timing and refresh control is performed by the FPGA.

FPGA configuration data and system software are stored on a SmartMedia card. The system can accommodate sizes from 2MBytes to 16MBytes. To reduce loading on the processor address/data busses, the SmartMedia card is accessed by the StrongARM via the isolated XBus. Special gating is provided for the SmartMedia CS pin to reduce susceptibility to accidental writes.

System setup information, option enables and other machine specific data is stored in a 16KByte serial EEPROM. The interface to the EEPROM is provided by the FPGA.

Control for a standard VGA format (640 x 480 pixels) LC display is provided by the FPGA. A connector is provided for an external CCFL backlight inverter as well as two digital controls for On/Off and brightness.

Acquisition Module

Transceiver/Power

Switch

Thermal Printhead

Power/Pixel Test Logic

MAC 5000 acquires ECG data with a new generation CAM-14 acquisition module. The FPGA provides the interface logic. Clocks and commands are transmitted to the acquisition module on a balanced RS485 line. Data is received similarly. Both directions are handled by a single RS485 transceiver. Power to the acquisition module is provided by a software controlled switch/current limiter.

Normal system operation is sufficient to verify the correct operation of the acquisition module interface. The module power switch/current limiter may be tested against spec as indicated elsewhere in this document.

The FPGA provides all the interface logic for the thermal print head. Power is controlled by a MOSFET switch whose gate drive is provided by a charge pump voltage doubler driven by the FPGA.

Additional circuitry is supplied to allow the measurement of individual dot resistance for automatic strobe width compensation and blown dot detection. A switchable constant current source (6mA) applies a test current to the TPH power bus. The TPH power bus voltage is then measured by Larry (one of the four analog inputs he continuously monitors). By loading a single black dot into the print head, it is possible to measure its resistance. A typical TPH has an average dot resistance of

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650 ohms. Presuming negligible driver leakage current, a single enabled dot would drop 3.9V. While there are mitigating influences (off-pixel driver leakage current and on-pixel driver saturation voltage) that might make accurate pixel resistance measurements difficult, it is certainly possible to differentiate pixels of nominal resistance from those that are blown open.

SuperIO Peripheral

Controller

Floppy Drive Support

Four RS-232 Serial Ports (one

dual mode RS-232/IrDA)

Clock/Calendar

A PC standard SuperIO peripheral controller provides floppy drive support, two serial channels (one IrDA compatible) a clock/calendar and some miscellaneous parallel port I/O.

The SuperIO provides support for a 3.5” 1.44MByte IBM format floppy diskette drive. The FPGA provides DMA like interrupt support for the floppy controller. A special chip select supplies the DMA acknowledge signal that gates data to/from the SuperIO floppy controller via the XBus. To ensure no data is lost, the floppy DMA request is routed to the StrongARM’s FIQ input.

Four serial ports are provided on two back panel Mini-DIN 8 pin connectors. Two serial ports (COM1 and COM2) are provided by the SuperIO device and two (COM3 and COM4) are provided by the FPGA. The SuperIO UARTs are full featured 16550 equivalents while the FPGA ports are minimal implementations with a limited set of bit rates, a single 8N1 format and no handshake lines. COM3 and COM4 are remultiplexed onto the COM1 handshake lines (see FPGA section more COM3/4 details).

The SuperIO device provides a clock/calendar function. Backup battery power is provided by a "super" capacitor with sufficient storage capacity to power the clock for hours. This backup source provides more than sufficient time to exchange battery packs when necessary.

External PS-2 Keyboard Port

General Purpose Parallel I/O Lines

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External card/bar code readers may be connected to the MAC5000 via a PS-2 compatible keyboard port. A small amount of 5V power is available at the connector to power the external device. Power faults are detectable.

The SuperIO device provides 16 general purpose parallel I/O lines. These are used for various control and sensing purposes about the design.

System management and some low level I/O functions are implemented in preprogrammed 68HC05 microcontrollers. Moving some I/O functions out into small processors relieves the StrongARM of burdensome real-time chores and moves the control hardware closer to the controlled devices, potentially reducing EMI. Localizing control also promotes reuse in future designs as the functions are self contained and reasonably portable.

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Although there are four of these little fellows in the MAC 5000, each performing a different function, there is only one firmware image. By merging the code from each of the four functions into a single ROM image confusion is reduced. It is impossible to place a processor in the wrong spot on the board.

Startup Self Identification

BBus

Curly

As each controller is released from reset, it executes a common "WhoAmI" routine to determine its identity on the board. Each controller’s environment is uniquely and easily identified with a few port pin tests. Once the identity is discovered, the code jumps to the appropriate entry point in the unified image and microcontroller assumes the desired personality.

Three of the four stooges (Moe, Larry and Shemp) communicate with the StrongARM via BBus connections. BBus is a single wire, half-duplex serial connection that places minimal hardware requirements on the microcontroller while yielding respectable bit transfer rates (~50KBps). A common set of BBus commands allow the StrongARM to access 128 bytes of RAM in each microcontroller. This dual port access allows the StrongARM to examine and modify internal variables in each controller while code is executing. This ability is used to allow the unalterable HC05 code to handle modest changes in hardware, such as changes in paper drive gearing or battery pack capacity.

Curly is responsible for configuring the FPGA and loading the first level bootstrap program into the StrongARM. When Reset is released, Curly reads the PCB ID code from three port pins and then searches the SmartMedia card via the XBus data bus for a matching FPGA configuration image (pages with ID "Xn" where n is the 3-bit PCB ID code 1-8). Once located, the configuration image is loaded into the FPGA. Included in the FPGA internal logic is "bus-unpacking" circuitry that constructs 32-bit wide StrongARM instructions from sequences of bytes on the X data bus. During the earliest phase of the startup process, these bytes are read from the SmartMedia card by Curly and then loaded into the "bus-unpacker". This early bootstrap code is stored in the SmartMedia card in a special format that Curly understands and contains a small program that enables the StrongARM to read the SmartMedia card by itself. Once this first stage bootstrap program is loaded (SmartMedia ID of "Bn", where n is the PCB ID) the StrongARM is able to read the SmartMedia card without Curly’s help and Curly shuts off (effectively disappearing from the circuit) until the next system startup.

Shemp

Shemp scans the keyboard and queues key presses for the StrongARM. Key presses are reported both on press and release, allowing system software to implement auto-repeat as well as the continuous operation of treadmill control keys (up/down, faster/slower). A special key code indicates when all keys are up as a safeguard against stuck keys in the application software.

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Larry

Larry controls the paper drive motor and quantizes the analog inputs. Since Larry’s code is not field alterable, every motor control parameter is alterable via BBus. Hopefully this renders the code immune to minor changes in the printer drive train.

Larry controls the motor speed by delivering a DAC controlled drive voltage to the motor windings. The 6-bit DAC is implemented using discrete, binary-weighted resistors directly driven by Larry’s port pins. The DAC output voltage is compared to a filtered fraction of the applied DC motor voltage by a comparator. If the motor feedback voltage is below the DAC voltage, the comparator turns on the motor via an HBridge driver. One motor terminal (which one is a function of motor direction) is always grounded. The other is alternately driven to either 12V or ground. The duty cycle of the drive signal determines the average applied voltage and therefore the average motor speed. The feedback voltage signal is the average of both motor terminals. Since one terminal is always grounded and the other is driven with a variable duty cycle between zero and 12V, the feedback signal is positive regardless of motor direction. An RC filter provides a DC feedback voltage from the chopped motor drive.

Cue and out-of-paper conditions are sensed via the thermal print head’s integral optical cue sensor.

Four analog inputs are digitized by Larry:

Moe

■ TPH Temperature

■ TPH Dot Resistance

■ External Analog Input #1

■ External Analog Input #2

The sampling rate is indeterminate, but guaranteed to be at least 100Hz. The external analog inputs are intended to be DC signals from devices such as ergo bikes or NIBP meters, so no effort is made to synchronize sampling with the ECG signal. All input signals are low-pass filtered to avoid aliasing EMI. The external analog input range is 0-10V. Zero volts produces a code of zero, 10V produces a code of 0xff. The TPH dot resistance input has a nominal sensitivity of 3.32 Ohms/count. A nominal print dot (650 Ohms) would produce a reading of 196.

Moe is responsible for controlling and monitoring the battery, power supplies, on/off key, system reset and related functions. Moe runs continuously (on +3V-C), even in the absence of AC power. This continuous operation is necessary for Moe to accurately monitor the battery state of charge.

System Startup

When the system is off and the user presses the power key, Moe begins the startup sequence. If the battery contains sufficient charge, or if AC power is applied, the mainCPU power supplies (+3V-M and +5V-M) are enabled and after a suitable stabilization period nSysReset is released. Moe then keeps tabs on the system via a software watchdog that must

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be serviced by specific BBus activity from the StrongARM. Moe himself is monitored by a self contained MAX823 watchdog timer / brownout detector. Moe must constantly toggle the MAX823 watchdog input pin or suffer the consequences.

Note: Moe presumes that the main power rails are off when he powers up. If +3V-M is up when Moe restarts the self ID code will incorrectly assume that Moe is actually Larry. As +3V-M is controlled by Moe, this should never happen. Even if Moe halts while operating, the minimum MAX823 reset period of 100ms virtually guarantees that +3V-M will be down before Moe comes out of reset (HC05 port pins tri-state in reset and the main power enable input to the MAX782 switching regulator is pulled down by a resistor).

When nSysReset is released, Curly configures the FPGA and starts the StrongARM from information stored in the SmartMedia card. Moe expects the StrongARM to request status via the BBus interface within a few seconds of startup. If that request doesn’t arrive in time, Moe places the system back in reset and removes power.

AC Power/Battery/Charger

Battery and system power management is entirely Moe’s responsibility.

An off-the-shelf 28V 1A universal input power supply provides operating/charging power for the MAC 5000. Located in the bottom of the chassis, the power supply is disconnected from theCPU when the lid is open. The battery connection is maintained through the hinge, so the CPU is capable of operating for a limited time with the door open.

A self-aligning connector routes power and motor signals from the power supply compartment to the CPU. When the lid is closed the DoorOpen signal is shorted to ground. When the lid is open a pullup resistor ensures a high level on DoorOpen. Moe monitors this line to detect lid open conditions which are reported to the system software to avoid misinterpretation of motor fault indications. When the door is open, the motor connections are lost and Larry receives no tachometer feedback from the motor. Without knowing the cause of the lost tach info, Larry can only respond with a paper jam condition. Moe’s knowledge of the lid state is used to suppress this error message as well as prevent further print operations.

AC Power Monitor

Moe senses the presence of AC power. The battery charger will not be enabled unless AC power is detected.

Ambient Thermistor

Extreme hot/cold ambient conditions are not favorable for battery charging. Rapid changes in ambient temperature can cause premature or delayed charge termination by altering the packs temperature. Moe monitors ambient temperature to ensure that charging occurs only within the "safe" temperature range as well as to minimize the effects of changing ambient temperature on charge termination (particularly to

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avoid premature termination, which would give a false "full" reading on the gas gauge).

Battery Pack

The MAC 5000 uses a 15-cell nickel metal hydride (NiMH) battery pack with integral thermal sensor for charge termination detection and self resetting fuse for short circuit protection. Charge current and normal system operating power are obtained from the AC power supply. The charger circuitry monitors both battery charge current and power supply output current. The battery is always charged at the maximum rate possible but system power demands take precedence over charger demands. The charger automatically reduces charge current as required to keep the AC power supply output current within specified limits. In the extreme (during printing) charging ceases and energy is taken from the battery to meet peak system demands. When system power draw declines, all excess power supply capacity is once again delivered to the battery.

Battery Thermistor

The thermal sensor is used by Moe for termination of charge. During normal charge, the electrical energy obtained from the power supply is stored in chemical reactions in the battery. When the battery reaches full charge there are no more reactants available in which to store chemical energy and the supplied charge power is converted directly to heat. The sudden rise in pack temperature caused by this release of heat is an indicator of full charge. When the rate of pack temperature rise exceeds a certain threshold, charge is terminated. This is the only normal charge termination mechanism, though abnormal conditions (battery or ambient temperatures beyond spec or excessive pack voltage) may also terminate charge. Once fully charged, the battery is maintained by low duty cycle charge current pulses.

Charge Light

Moe provides power to the amber charge light in the power supply compartment. Moe communicates the current battery/charger state via this light.

Four conditions may be indicated:

■ Battery charged (light is off)

■ Battery needs charge (light blinks once per second)

■ Battery is critically low (light flashes furiously)

■ Battery is charging (light on continuously)

Battery Gauge

Current flow into and out of the battery pack is monitored by Moe via a MAX472 current sensor (IMON). By integrating the current flow, Moe is able to maintain a reasonable estimate of the battery pack’s charge. The current sensor hasn’t sufficient dynamic range to cover the full scale of system current draw so some compromises are made. The very highest

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peak currents (drawn during printing) are clipped to the current monitor’s full scale value. The effects of this are minimal as such high density printing occurs for short periods of time and represents only a small portion of system energy consumption. Quantization error limits the ability to measure the small current that flows when the system is off. To compensate for this, Moe presumes a small constant quiescent current flow from the battery. This flow serves to drain the gauge at a rate estimated to mimic the self discharge and system quiescent current draws.

Operation with Discharged Batteries

On AC power, the MAC 5000 can operate indefinitely with a discharged battery, though it may not be able to print until sufficient charge has been placed in the pack to support peak current demands. Normally, only a minute or two of charge is sufficient to get through the printing of a single page report.

Main Power Supplies

The MAC 5000 contains a mix of 3.3 and 5V logic. Both supply rails are provided by a high efficiency synchronous buck regulator device (Maxim MAX782). This device is the "Swiss army knife" of switching regulators, providing the main logic rails as well as 3V-C, which powers Moe. A medium current (1A) semi regulated 13V output is also provided to feed a pair of low current linear regulators as well as provide power for other loads. One of the low current linear regulators is used to provide 12V for the analog output hardware. The semi-regulated rail is also used to power the acquisition module.

Acquisition Module Power Switch/Regulator/Current Limiter

A discrete MOSFET based linear regulator applies crude regulation to the MAX782 semi-regulated rail for use by the acquisition module. The regulator may be turned on/off under software control and contains a built in current limiter/sensor to protect against short circuits.

Main 12V Rail

An integrated switching regulator provides 12VDC for the LCD backlight, motor and external peripheral devices. Input power to the regulator is controlled by a MOSFET power switch under software control.

External 12V Rail Switch/Current Limiter

12V power for external peripherals (modem or suction electrode pump) is switched, current limited and fault detected by a MOSFET switch under software control. The current limiter allows momentary excursions above the nominal current limit to allow for KISS suction pump startup transients.

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Untested "Nominal"

Operating Time Specs

These specifications are affected by battery pack characteristics. While they are of interest, it is not possible to test them in production. These are "nominal specs" and are only guaranteed for a new battery pack of

3.5A capacity. As the following specs are for a system that is turned off, they are deliverable by the CPU regardless of other system components.

Nominal charge time:

5 Hours

Max off time from gauge full till loss of clock: 1 Month

Max off time from gauge just empty till loss of clock: 3 Days

Max off time from panic shutdown till loss of clock: 1 Day

Maximum time from removal of live battery to loss of clock: 6 Hours

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6 Parts Lists and Drawings