Okidata OL850, OL830Plus Service Manual

Page: 1

Service Guide OL830Plus/OL850

Chapter 0 About This Manual

OL830Plus // OL850

LED Page Printers

Adobe Acrobat printable reference

copy of the OKIDATA Service Training Manual.

09/17/97

Note: This Adobe Acrobat version of the Okidata Service Training Manual was built with the

pictures rendered at 300 dpi, which is ideal for printing, but does not view on most displays well.

Table of Contents Page

Service Guide OL830Plus/OL850

0 About This Manual

Front Cover 1 Manual Copyright 2

1 Product Specifications

1.1 General Description 3

1.2 Specifications 4

1.3 Paper Specifications 5

1.4 Physical Specifications 6

1.5 Power Requirements 7

1.6 Environmental Conditions 8

1.7 Agency Approvals 9

1.8 Options 10

1.9 Memory Specifications 11

1.10 Consumables 12

1.11 Printer Reliability 13

2 Principles of Operation

2.1 Principles of Operation - Printer Overview 14

2.2 Control Unit (CU) 15

....2.2.01 Main Controller Board Overview 16

....2.2.02 Main Controller Board Functions 17

....2.2.03 Optional Extended RAM Board (REXM) 18

....2.2.04 Font Card 19

2.3 Printer Unit (PU) 20

....2.3.01 Engine Board Controller (LLAT) 21

....2.3.02 Engine Controller Board Operations 22

....2.3.03 EEPROM Operation 23

....2.3.04 Power Supply Unit 24

....2.3.05 Fuser Unit 25

....2.3.06 Main Motor (Drum Motor) 26

....2.3.07 LED Array 27

....2.3.08 Resist Motor 28

....2.3.09 DC Fan 29

....2.3.10 Operation Panel 30

....2.3.11 Second Paper Tray Mechanism 31

2.4 Mechanical Operation Description 32

....2.4.02 OL830-Plus/850 Printing Process 33

....2.4.03 Process Descriptions 34

2.5 Sensors And Switches 35

....2.5.02 Sensor Functions 36

3 Maintenance & Disassembly

3.1 Maintenance - General Information 37

....3.1.02 Maintenance Tools 38

Table of Contents Page

....3.1.03 Maintenance Precautions 39

3.2 Disassembly/Assembly Procedures - General Information 40

....3.2.01 Preliminary Items 41

....3.2.02 Upper Cover 42

....3.2.03 Stacker Open Switch Assembly 43

....3.2.04 LED Head 44

....3.2.05 RS232 Interface Board (APSR) 45

....3.2.06 RAM Expansion Circuit Board (REXM) Option 46

....3.2.07 Emulation Board (APSH) 47

....3.2.08 Main Controller Board (APSM) 48

....3.2.09 Engine Controller Board (LLAT) 49

....3.2.10 Pulse Motor (Main) 50

....3.2.11 Idle Gear A, Idle Gear B, and Speed Reduction Gear 51

....3.2.12 DC Fan Assembly 52

....3.2.13 Power Supply Unit 53

....3.2.14 Cover Open Microswitch Assembly 54

....3.2.15 Paper Eject Roller Assembly 55

....3.2.16 Paper Eject Sensor Lever and Rollers 56

....3.2.17 Upper Unit 57

....3.2.18 Cover Open Switch Actuator 58

....3.2.19 Paper Eject Sensor Levers B and C 59

....3.2.20 Fusing Unit 60

....3.2.21 Metal Pressure Roller Assembly 61

....3.2.22 Resist Sensor Lever and Toner Sensor Lever 62

....3.2.23 Lock Lever Assembly 63

....3.2.24 LED Head Holder 64

....3.2.25 LED Holder Ground Plate 65

....3.2.26 Back-up Roller Assembly 66

....3.2.27 Transfer Charger Assembly 67

....3.2.28 Registration Roller Assembly 68

....3.2.29 High Voltage Connector 69

....3.2.30 Idle Gear and Post 70

....3.2.31 Paper Delivery Unit 71

....3.2.32 Resist Motor 72

....3.2.33 Engine Connector Board, LLCC 73

....3.2.34 Hopping Roller A 74

....3.2.35 Separator 75

....3.2.36 Base Frame 76

....3.2.37 Ozone Filter 77

....3.2.38 Second Paper Feed Unit (Option) 78

....3.2.39 Boards and Connectors (Second Paper Feed Unit) 79

....3.2.40 Paper Delivery Unit (Second Paper Feed Unit) 80

....3.2.41 Cassette Spring (Second Paper Delivery Unit) 81

....3.2.42 Resist Motor (Second Paper Delivery Unit) 82

Table of Contents Page

....3.2.43 Control Board, LLFC (Second Paper Delivery Unit) 83

....3.2.44 Hopping Roller (Second Paper Delivery Unit) 84

....3.2.45 Separator (Second Paper Delivery Unit) 85

3.3 Adjustments And Service Settings 86

....3.3.02 Actual Page Count 87

....3.3.03 Modified Page Count 88

....3.3.04 Drum Counter Reset 89

....3.3.05 Fuser Counter Reset 90

....3.3.06 Vertical Print Start Position Adjustment 91

....3.3.07 Darkness Control 92

....3.3.08 Smoothing Select 93

....3.3.09 Setting the LED Head Drive Time 94

....3.3.10 DC Voltage Check (+5 vdc) 95

3.4 Cleaning 96

....3.4.02 Cleaning Table 97

....3.4.03 Static Charger 98

....3.4.04 Hopping Roller 99

....3.4.05 Printer Unit 100

....3.4.06 Transfer Charger 101

....3.4.07 LED Lens Array 102

3.5 Lubrication 103

4 Failure & Repair Analysis

4.1 Overview 104

4.2 Troubleshooting Updates - General Information 105

....4.2.02 Okilink II 106

....4.2.03 Faxable Facts 107

....4.2.04 Technical Service Bulletins 108

4.3 Reporting Problems - General Information 109

....4.3.02 Problem Lists 110

....4.3.03 Reporting Methods 111

4.4 Troubleshooting Tips - Preliminary Checks 112

....4.4.02 Tips for Preventing Image Problems 113

4.5 LCD Error Messages - Using The Error Message Charts 114

....4.5.02 Error Messages (Service Lamp ON) 115

....4.5.03 Error Messages (Service Lamp OFF) 116

....4.5.04 Samples of Abnormal Output 117

4.6 Repair Analysis Procedures Using The RAPS 118

....4.6.02 RAP Index 119

....4.6.03 Start Here Flowchart 120

........RAP 01: Printer Does Not Initialize 121

........RAP 02: Paper Feed Jam 122

........RAP 03: Paper Jam 123

........RAP 04: Paper Size Error 124

........RAP 05: Fusing Problem 125

Table of Contents Page

........RAP 06: PU Error 126

........RAP 07: Operator Panel Communication Error 127

........RAP 08: Communication Error Between PU and CU 128

........RAP 09: Loop Test Failure (RS-232C) 129

........RAP 10: Resident/Optional RAM Failure 130

........RAP 11: Program ROM Failure 131

........RAP 12: Optional Font Card Failure 132

........RAP 13: Receive Buffer Overflow 133

........RAP 14: No Display on Operator Panel 134

........RAP 15: Images are Light or Blurred 135

........RAP 16: Dark Background Density 136

........RAP 17: Blank Paper is Output 137

........RAP 18: Black Vertical Stripes 138

........RAP 19: Evenly Spaced Marks on Output 139

........RAP 20: Random Missing Output 140

........RAP 21: White Vertical Stripes 141

........RAP 22: Black Page is Output 142

4.7 Printer Tests 143

....4.7.02 Continuous Print (Rolling ASCII) Test 144

....4.7.03 Serial Interface Diagnostic 145

....4.7.04 Engine Test - A 146

....4.7.05 Engine Test - B 147

....4.7.06 Menu Print 148

....4.7.07 Demo Page Print 149

A Board Diagrams

A.1 Board Diagrams - General Information 150 A.2 Index To Charts 151

....A.2.01 Main Controller Board (APSM) 152

....A.2.02 Engine Control Board (LLAT) 153

....A.2.03 Operator Panel Board (LLJB) 154

....A.2.04 Engine Connection Board (LLCC) 155

....A.2.05 Power Connection Board (LLID) 156

....A.2.06 AppleTalk/Serial Interface Board (APSR) 157

....A.2.07 Memory Expansion Board (REXM) Option 158

....A.2.08 Emulation Board (APSH) 159

....A.2.09 Power Supply Unit 160

....A.2.10 Second Paper Supply Unit Board (LLIG) 161

....A.2.11 Second Paper Supply Unit Board (LLFC) 162

....A.2.12 Second Paper Supply Unit Board (LLIF) 163

B Illustrated Parts Listing

B.1 Illustrated Parts Listing - General Information 164

....B.1.02 Definitions of Terms 165

....B.1.03 Parts Ordering Information 166

B.2 Charts 167

Table of Contents Page

....B.2.01 Printer Unit 168

....B.2.02 Paper Trays 169

....B.2.03 Upper Unit (1 of 2) 170

....B.2.04 Upper Unit (2 of 2) 171

....B.2.05 LED Holder 172

....B.2.06 Lower Unit (1 of 2) 173

....B.2.07 Lower Unit (2 of 2) 174

....B.2.08 Boards 175

....B.2.09 Paper Eject Roller Assembly 176

....B.2.10 Paper Delivery Unit 177

....B.2.11 Second Paper Feed Unit 178

....B.2.12 Packing Materials 179

....B.2.13 Consumables 180

....B.2.14 Options 181

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Service Guide OL830Plus/OL850

Chapter 0 About This Manual

Manual Copyright

This document may not be reproduced without written permission of the Okidata® Technical Training Group. Every effort has been made to ensure the accuracy of the information contained in this training course. Okidata is not responsible for errors beyond our control.

© 1994 by Okidata All rights reserved. Second Edition April, 1994 Written and produced by the Okidata Technical Training Group Please send any comments on this publication to the address listed below. Technical Training Group Okidata 532 Fellowship Road Mount Laurel, NJ 08054-3499 Facsimile Number: (609) 235-2600, ext. 7034. Okilink Login Name: Technical Training OKI is a registered trademark of Oki Electric Industry Company, Ltd.; marques deposee de Oki Electric

Industry Company, Ltd.; marca registrada, Oki Electric Industry Company, Ltd. OKIDATA is a registered trademark of Oki Electric Industry Company, Ltd.; marques deposee de Oki

Electric Industry Company, Ltd.; marca registrada, Oki Electric Industry Company, Ltd. MICROLINE is a registered trademark of Oki Electric Industry Company, Ltd.; marque depose de Oki

Electric Industry Company, Ltd. Adobe and PostScript are trademarks of Adobe Systems Incorporated, which may be registered in certain

jurisdictions. Hewlett-Packard, HP, and LaserJet are registered trademarks of the Hewlett-Packard Company. Bitstream is a registered trademark of Bitstream Incorporated. IBM and PC are registered trademarks of International Business Machine Corporation. MS-DOS is a registered trademark of Microsoft Corporation.

PC is a registered trademark of International Business Machine Corporation. Windows is a trademark of Microsoft Corporation

Page: 3

Service Guide OL830Plus/OL850

Chapter 1 Product Specifications

1.1 GENERAL DESCRIPTION

1.1.01 General Information

The OL830-Plus and OL850 are desktop page printers, which use a stationary LED head and dry electrophotography as their exposure and development methods. The printers have a resolution of 300 x 300 dots per inch and a continuous print speed of 8 letter-sized sheets per minute. A two megabyte page memory is standard on the OL830-Plus and OL850 Printers. This can be expanded to a total of four megabytes of printer memory. The OL830-Plus and OL850 feature Oki Smoothing Technology (OST). The OST LED head provides edge smoothing to reduce the jagged stair step effects of bit mapped images for improved print quality. The OST capability is selected through the Smoothing option of the printer menu. The default setting is Smoothing On. The OL830-Plus provides PostScript capability, along with HP LJII and Diablo 630 ECS emulations. Seventeen Adobe PostScript fonts are standard on the OL830-Plus. In HP LaserJet II emulation, 26 bit-mapped fonts are available. The Diablo emulation includes 18 bit-mapped fonts. A Centronics Parallel Interface is standard on the OL830-Plus.

The OL850 provides PostScript capability, along with HP LJII and Diablo 630 ECS emulations. Sixty-five Adobe PostScript fonts (35 resident and 30 down-loadable) are standard on the OL850. In HP LaserJet II emulation, 26 bit-mapped fonts are available. The Diablo emulation includes 18 bit-mapped fonts. A Centronics parallel interface and an AppleTalk/ Serial Interface are standard on the OL850.

Each printer contains a font card slot. A variety of optional font cards are available. The OL830-Plus and the OL850 also accept downloadable fonts.

Two consumable kits are used in the printers. The toner cartridge kit contains a toner cartridge, a fuser cleaner pad, and an LED lens cleaner. The other consumable package, the image drum cartridge kit, includes an image drum cartridge and an ozone filter.

A letter-size paper tray is included with each printer. Legal, envelope, executive, and A4 trays are also available. Paper feeding can be done automatically or manually. A second paper feed unit is also available.

The printers will print on a variety of paper types, labels, envelopes, and transparencies.

Service Guide OL830Plus/OL850

Chapter 1 Product Specifications

1.2 SPECIFICATIONS

1.2.01 Print Specifications

· Exposure method: Stationary LED Head

· Development method: Dry electrophotography

1.2.02 Print Speed

· First print: 14 seconds typical (letter size paper after warm-up)

· Continuous print: 8 sheets per minute (letter size)

· Warm-up time: 50 seconds

1.2.03 Paper Feed Methods

· Automatic Feed

· Manual Feed

Page: 4

1.2.04 Paper Delivery Methods

· Face down

· Face up

1.2.05 Print Resolution

· 300 x 300 dots/inch

1.2.06 Emulations

OL830-Plus

· Adobe PostScript

· HP LaserJet II

· Diablo 630 ECS

OL850

· Adobe PostScript

· HP LaserJet II

· Diablo 630 ECS

1.2.07 Symbol Sets

· HP II Emulation

- US ASCII

- ROMAN-8

- ROMAN EXTENSION

- LEGAL

- HP German

- HP Spanish

- INTERNATIONAL

- IBM Character

· Diablo Emulation

- Courier

- Courier Legal

- Multi-purpose 10

1.2.08 Available Fonts

OL830

· PostScript: 17 fonts / 5 families

· HP II Emulation: 26 bit-mapped fonts / 4 faces

· Diablo 630 ECS Emulation: 18 bit-mapped fonts

OL850

· PostScript: 65 fonts / 26 families 35 resident fonts 30 software fonts

· HP II Emulation: 26 bit-mapped fonts / 4 faces

· Diablo 630 ECS Emulation: 18 bit-mapped fonts

1.2.09 Interface Methods

· Centronics Parallel Interface

· AppleTalk - RS422 / RS-232C Interface (optional for OL830-Plus)

1.3 PAPER SPECIFICATIONS

1.3.01 Paper Types

· Letter

- Size: 8.5" x 11" (216 mm x 279 mm)

- Feed: Automatic or Manual

- Weight Minimum: 16 lbs. (60 g/m 2 ) Maximum: 24 lbs. (90 g/m 2 ) Recommended: 20 lbs. (75g/m 2 )

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Service Guide OL830Plus/OL850

Chapter 1 Product Specifications

· Legal

- Size: 8.5" x 14" (216 mm x 356 mm)

- Feed: Automatic (with optional paper tray) or Manual

- Weight Minimum: 16 lbs. (60 g/m 2 ) Maximum: 24 lbs. (90 g/m 2 ) Recommended: 20 lbs. (75g/m 2 )

· Executive

- Size: 7.25" x 10.5" (184 mm x 267 mm)

- Feed: Automatic (with optional paper tray) or Manual

- Weight Minimum: 16 lbs. (60 g/m 2 ) Maximum: 24 lbs. (90 g/m 2 ) Recommended: 20 lbs. (75g/m 2 )

· A4

- Size: 8.27" x 11.69" (210 mm x 297 mm)

- Feed: Automatic (with optional paper tray) or Manual

- Weight Minimum: 16 lbs. (60 g/m 2 ) Maximum: 24 lbs. (90 g/m 2 ) Recommended: 20 lbs. (75g/m 2 )

· Envelope

- Size Minimum: 3.5" x 7.5" (89 mm x 191 mm) Maximum: 7.2" x 10.1" (183 mm x 257 mm)

- Feed: Automatic (with optional paper tray) or Manual

- Weight Minimum: 16 lbs. (60 g/m 2 ) Maximum: 24 lbs. (90 g/m 2 ) Recommended: 20 lbs. (75g/m 2 )

· Labels

- Manual feed / Face up delivery only

- Use labels designed specifically for laser printers.

· Transparencies

- Manual feed / Face up delivery only

- Must be able to withstand the heat of the fusing process.

CAUTION:

Envelopes, labels, and transparencies should only be fed from the top paper tray.

Service Guide OL830Plus/OL850

Chapter 1 Product Specifications

1.4 PHYSICAL SPECIFICATIONS

1.4.01 Outside Dimensions

· Width: 17.72" (450 mm)

· Height: 6.02" (153 mm)

· Depth: 23.4" (450 mm) [includes letter size paper tray]

1.4.02 Printer Weight

· 24 pounds without options (approximately 11 kg)

· 41 pounds with second paper feed unit and second paper tray (approximately 19 kg)

1.4.03 LED Array

· Number of LED Elements: 2560

CAUTION:

The OST LED Head for the OL830-Plus / OL850 is

not

interchangeable with non-OST LED Page Printers.

Page: 6

Page: 7

Service Guide OL830Plus/OL850

Chapter 1 Product Specifications

1.5 POWER REQUIREMENTS

1.5.01 Input Power

· 120 VAC +5.5%, -15%

· 220/240 VAC +/-10%

1.5.02 Power Consumption

· Approximately 800 W maximum during operation

· Approximately 22 W maximum during stand-by (Fuser is OFF)

Page: 8

Service Guide OL830Plus/OL850

Chapter 1 Product Specifications

1.6 ENVIRONMENTAL CONDITIONS

1.6.01 Ambient Temperature and Relative Humidity

· While operating:

- 50° to 90° F

- 10° to 32° C

- 20 to 80% Relative Humidity

· While in storage:

- -4° to 110° F

- -20° to 43° C

1.6.02 Printer Noise Level

· In operation: 52 dB maximum

· In stand-by (QUIET Mode): 43 dB maximum

· In stand-by (Non-QUIET Mode): 45 dB maximum

Service Guide OL830Plus/OL850

Chapter 1 Product Specifications

1.7 AGENCY APPROVALS

· 120 VAC Type

- FCC Class B

- UL478 Version 5 (Partial Version 4)

- CSA 22.2 - 220

- Radio Interference Regulations of Canadian Department of Communications

· 220/240 VAC Type

- FCC Class A

Page: 9

Page: 10

Service Guide OL830Plus/OL850

Chapter 1 Product Specifications

1.8 OPTIONS

1.8.01 RAM Expansion Board

· RAM Expansion Board (REXM): Two Mbyte

1.8.02 Font Card

· Refer to

1.8.03 AppleTalk / Serial Interface Board

· This board is standard on the OL850 Printer

· RS-232C Serial: Provides serial communication capability at speeds up to 19.2 Kbps

· AppleTalk / RS-422 (accessed in PostScript Mode only)

1.8.04 Second Paper Feed Mechanism

· The second paper feed mechanism allows paper feeding from two paper trays. A second paper tray must be purchased for use with the second paper feed mechanism.

Printer Handbook - Appendix G

or Okilink II for a listing of available cards.

1.8.05 Paper Trays

· Letter size

· Legal size

· Envelope

· Executive

· A4

1.9 MEMORY SPECIFICATIONS

1.9.01 ROM (Read Only Memory)

· Main Controller Program Rom

- OL830-Plus 1 Mbyte

- OL850 1 Mbyte

· Engine Controller ROM

- Not used; masked to the CPU

1.9.02 RAM (Random Access Memory)

· Resident RAM = 2 Mbytes

· Expansion RAM (Option)

- 2 Mbytes (RAM Expansion Board)

Page: 11

Service Guide OL830Plus/OL850

Chapter 1 Product Specifications

1.9.03 EEPROM (Electrically Erasable Programmable Read Only Memory)

· Main Controller EEPROM

- 1024 x 1 bit serial input/output

· Engine Controller EEPROM

- 1024 x 1 bit serial input/output

Page: 12

Service Guide OL830Plus/OL850

Chapter 1 Product Specifications

1.10 CONSUMABLES

1.10.01 Image Drum Cartridge Kit

Includes:

· Image Drum Cartridge

· Ozone Filter

1.10.02 Toner Cartridge Kit

Includes:

· Toner Cartridge

· Fuser Cleaner Pad

· LED Lens Cleaning Pad

1.10.03 Toner Toxicity

· No carcinogin is contained

Service Guide OL830Plus/OL850

Chapter 1 Product Specifications

1.11 PRINTER RELIABILITY

1.11.01 Mean Pages Between Failure (MPBF)

· Approximately 32,000 pages

1.11.02 Mean Time To Repair (MTTR)

· Approximately 20 minutes

1.11.03 Estimated Printer Life

· Five Years or approximately 300,000 pages

1.11.04 Estimated Fuser Life

· Approximately 180,000 pages

1.11.05 Printer Duty Cycle

· Approximately 12,000 pages per month @ 5% print density

Page: 13

Page: 14

Service Guide OL830Plus/OL850

Chapter 2 Principles of Operation

2.1 PRINTER OVERVIEW

2.1.01 General Information

This section describes the operation of the OL830-Plus/850 in the order listed below.

· Control Unit (CU)

· Printer Unit (PU)

· Mechanical Operation of the OL830-Plus/850

· OL830-Plus/850 Sensors and Switches

Page: 15

Service Guide OL830Plus/OL850

Chapter 2 Principles of Operation

2.2 CONTROL UNIT (CU)

The control unit regulates the reception of data from the host system interface. After receiving data and commands from the host system, the CU generates bit image data. The CU transfers data and commands to the Printer Unit (PU).

The principal hardware components of the CU are listed below.

· Main controller board

· Serial interface board (Option on OL830-Plus)

· Emulation board

· Extended RAM board (Option)

· Font card (Option)

Control Unit (CU) - Block Diagram

Page: 16

Service Guide OL830Plus/OL850

Chapter 2 Principles of Operation

2.2.01 Main Controller Board Overview

The major components of the main controller board consist of a 25 Mhz oscillator, a Motorola 68000 Microprocessor (CPU), two 1 Mbyte Program ROMs (4 PROMs are used on the OL850), 2 Mbyte of RAM, an EEPROM, and a two Gate Arrays. The main controller board is connected to the host system through a Centronics parallel interface or the RS-232C serial / RS422 / AppleTalk interface. The RS232/RS422/AppleTalk interface is standard on the OL850. The main controller board is connected to the printer unit via CN7 on the main controller board and J7 on the printer units engine controller board.

Two Gate Arrays are located on the main control board. The Gate Arrays can read/write/ process data simultaneously in accordance with the 12.5 Mhz clock pulse. The Gate Arrays control the following functions:

· Gate Array #1

- Controls reading data from, and writing data to, the dynamic RAM

- Provides the dynamic RAM refresh

- Sends a 12.5 Mhz clock signal to the microprocessor. This clock pulse governs the processing and executing of commands by the CPU.

· Gate Array #2

- Reads/Writes data from/to the EEPROM. The EEPROM, located on the main controller board, stores the default interface protocol information.

- Controls the printer interface (parallel, serial and AppleTalk)

- Controls the printer unit

Page: 17

Service Guide OL830Plus/OL850

Chapter 2 Principles of Operation

2.2.02 Main Controller Board Functions

- Reception control

- Command analysis processing

- Font processing

- Raster buffer read operation

- Engine interface (I/F) processing

- Operation panel control

Reception Control

I-PRIME: Enable/Disable of the parallel interface port can be specified through the menu. The RS-232C serial interface baud rate, parity, and busy control protocol are selected through the menu.

The RS422 / AppleTalk interface is active only in the PostScript operating mode.

Command Analysis Processing

The OL830-Plus/850 has the following emulation modes:

· PostScript

· Laser Jet Series II: Hewlett Packard

· Diablo 630 ECS

Font Processing

Outline fonts are used with the PostScript interpreter. Bit mapped fonts are available for HPLJ-II and Diablo emulations.

Raster Buffer Read Operation

Bit images written in the raster buffer are converted to serial data. The contents of the registers are transferred to the engine controller board.

Engine Interface (I/F)

Provides a control signal which governs the operation of the engine controller board when printing is requested.

Page: 18

Service Guide OL830Plus/OL850

Chapter 2 Principles of Operation

2.2.03 Optional Extended RAM Board (REXM)

The extended RAM Board (REXM) contains 2 Mbyte of RAM. This board, plus the resident RAM on the main controller board, extends the RAM capacity to 4 Mbytes. The CPU detects the extended RAM board by sending the MEMEXIST signal. The RAM capacity is identified during the power-on sequence, and can be verified by the operator by requesting a MENU PRINT operation.

Page: 19

Service Guide OL830Plus/OL850

Chapter 2 Principles of Operation

2.2.04 Font Card

An optional font card (for additional bit mapped/scalable fonts) can be attached to the main control board. The printer must be OFF-LINE (the READY lamp is off) before the card can be inserted or removed. If the font card is inserted or removed while the printer is ON- LINE (the READY lamp is on), a CARD REMOVED ON-LINE error message will appear on the operator panel display.

Service Guide OL830Plus/OL850

Chapter 2 Principles of Operation

2.3 PRINTER UNIT (PU)

The principal hardware components of the printer unit are listed below.

· Engine controller board

· Power supply unit

· Fuser unit

· Main motor

· LED array

· Resist motor

· DC fan

Page: 20

· Operation panel

· Second paper tray mechanism (Option)

· Image drum cartridge

· Sensors and Switches Toner end sensor, inlet sensor, outlet sensor, paper out sensor, paper tray identification switch, cover

open switch).

Page: 21

Service Guide OL830Plus/OL850

Chapter 2 Principles of Operation

2.3.01 Engine Board Controller (LLAT)

The PUs engine controller board contains an eight bit microprocessor (which has 128 Kbyte of internal RAM, 32 I/O ports, and 5 interrupt lines). The engine controller board also contains a one Kbyte EEPROM, a 120 pin LSI (which contains 36 I/O ports), two drivers (IC5/IC8), toner end sensor, inlet sensor, outlet sensor, comparator IC7, latch IC4, four driver transistors T21-T24, and two oscillators OSC1/OSC2.

Printer Unit (PU) - Block Diagram

+ 262 hidden pages

Okidata OL850, OL830Plus Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual