NCR PC4I User manual

PC4i
Service Manual

C op yright c 1986 by NC R Corporatio n
Dayton, Ohio
All R ig hts Reserved
Printed in the Federal Republic of Germany
March 1986
It is the policy of NCR Corporation to improve products as new
technology, components, software, and firmware become available.
NCR Corporation, therefore, reserves the right to change specifica
tions without prior notice.
All features, functions, and operations described herein may not be
marketed by NCR in all parts of the world. In some instances, photo
graphs are of equipment prototypes. Therefore, before using this docu
ment, consult your NCR representative or NCR office for information
that is applicable and current.

NCR PERSONAL COMPUTER PC i»i
SERVICE MANUAL
CONTENTS
Chapter 1 System Overview
NCR Personal Computer Hardware ................. 1-1
Display Unit .................................... 1-1
Models .......................................... 1-3
Model Numbers ................................... 1-5
Tools .......................................... 1-6
Alternate Main Processor Board ................. 1-8
Chapter 2 Basic Troubleshooting
Level 0 (Pov/er-On) Diagnostics ................ 2-1
Power On ...................................... 2-2
Power Cords and Switches ....................... 2-2
Memory Test Messages .......................... 2-3
After First Attempt ........................... 2-6
After Second Attempt .......................... 2-7
Power Supply ................................... 2-9
Peripherals
................................... 2-17
Check Keyboard ................................ 2-17
Check for Diagnostic Errors .................... 2-17
Restore Full Configuration .................... 2-19
Test Total Memory ............................. 2-19
Test CRT and Disk Drives ..................... 2-20
Re-Installation ............................... 2-22
Chapter 3 Level 0 Diagnostics
Memory Test ..................................... 3-1
Other MPB Tests ......... 3-5
Keyboard Test .................................. 3-5
Initialization and Loading .................. 3-5
Error Returns .................................. 3-6
Parallel Port Error Codes
...................... 3-7
Level 0 Loop Tests on Generic Processor Board .. 3-7
Error Messages of the Early-Type M P B .......... 3-11*
Suggested Action ............................... 3-15

Chapter 4 Level 1 Diagnostics
How to Begin Testing .......................... 4-1
Load the Diskette ........................... 4-1
Main Menu ..................................... 4-2
Main Menu Help Screens
........................ 4-5
Test Completion Displays ...................... 4-6
Diagnostic Selections ......................... 4-8
Run all Tests Once ........................... 4-9
Automatic Completion ......................... 4-9
Memory (Main Menu Selection 1) ............... 4-11
Memory Test Help Screens ...................... 4-12
RAM Pattern Test ............................. 4-12
RAM Address Test .............................. 4-13
RAM Parity Test ............................. 4-14
RAM Walking Ones Test ........................ 4-15
Firmware Checksum Test ........................ 4-16
Controllers (Main Menu Selection 2) ........... 4-17
Controllers Test Help Screens ................. 4-18
CPU Test ..................................... 4-18
DMA Test ...................................... 4-19
Flexible Disk Controller Test ................. 4-20
Interval Timer Test ........................... 4-21
Interrupt Controller Test ..................... 4-22
CPU Controller Test ........................... 4-23
Monochrome Display Controller Test ............ 4-24
Color Graphics Display Controller Test ....... 4-23
Serial Synchronous Controller Test ............ 4-26
Keyboard (Main Menu Selection 3) .............. 4-26
Flexible Disk Drive (Main Menu Selection 4) .... 4-28
Flexible Disk Drives HELP Screens ............. 4-28
Read Only Drive A Test ........................ 4-29
Read/Write Drive A Test ....................... 4-30
Fixed Disk Drive (Main Menu Selection 5) ..... 4-31
Fixed Disk Drive Test HELP S c r e e n ............ 4-32
Read/Write Maintenance Track ................. 4-32
Read Only Sector 0 ........................... 4-33
Read Only Entire Disk ......................... 4-34
Read/Write Entire Disk ........................ 4-35
Fixed Disk Controller ......................... 4-38
Monochrome Display (Main Menu Selection 6) ..... 4-39
Color/Graphics Display (Main Menu Selection 7).. 4-41
Peripherals (Main Menu Selection 8) .......... 4-47
Serial Port Loopback Test ..................... 4-48
Parallel Port Loopback Test ................... 4-49

Printer Tests ................................ 4-50
Generic Printer Test
.......................... 4-51
PC Compatible Printer Test ........... 4-52
Utilities ..................................... 4-53
Videotex Adapter Tests (Main Menu Selection).... 4-54
Local Test
................................... 4-55
Remote Test ................................. 4-55
Picture Test ................................. 4-57
Chapter 5 Level 1 Diagnostic Error Returns
Repair Guidelines ............................. 5-1
Basic System Configuration ..................... 5-1
Preliminary Checks ............................. 5-2
Main Processor Board Components ................ 5-3
Memory Addressing .............................. 5-5
Error Codes .................................... 5-8
Relationship between Detail Codes and
Repair Procedures ............................. 5-8
Format of Displayed Error Codes .............. 5-10
List of Major Error Codes
.................... 5-10
Memory Error Codes ........................... 5-12
Repair Procedure 01 ......................... 5-13
Repair Procedure 02 ......................... 5-18
Repair Procedure 03 5-20
Repair Procedure 04 5-21
Repair Procedure 05 5-21
Flexible Disk Drive Error Codes .............. 5-23
Repair Procedure 06 ......................... 5-25
Keyboard Error Codes ......................... 5-32
Repair Procedure 07 ......................... 5-32
Video Display Error Codes .................... 5-34
Repair Procedure 08 ......................... 5-35
Repair Procedure 09 ......................... 5-37
Peripheral Error Codes ....................... 5-38
Repair Procedure 10 5-40
Repair Procedure 11 5-43
Repair Procedure 12 5-46
Major System Controller Error Codes
.......... 5-39
Repair Procedure 13
......................... 5-47
Repair Procedure 14 ......................... 5-48
Repair Procedure 15 ......................... 5-48
Repair Procedure 16 ......................... 5-49
Repair Procedure 17 5-50

Repair Procedure 18 ......................... 5-51
Repair Procedure 19 ......................... 5-52
Repair Procedure 20 ......................... 5-52
Fixed Disk Controller Error Codes .............. 5-53
Repair Procedure 21 ......................... 5-53
Repair Procedure 22 ......................... 5-54
Videotex Error Codes ......................... 5-56
Repair Procedure 23 and 24 ................... 5-57
Repair Procedure 25 ......................... 5-57
Repair Procedure 26 ......................... 5-57
Chapter 6 Removal/Replacement
Cabinet ....................................... 6-1
Card Rack Assy ................................ 6-2
Printed Circuit Boards ........................ 6-4
Options PCBs ................................ 6-4
Main Processor Board .......................... 6-5
Disk Drives .................................. 6-7
ON/OFF Switch ................................ 6-9
Brightness and Volume Controls ............... 6-10
Monochrome CRT/Power Supply Assy .............. 6-11
Complete Assembly ........................... 6-11
Power Supply ................................ 6-12
Monochrome Deflection Board ................. 6-14
Monochrome CRT ............................. 6-15
Color CRT/Power Supply A s s y .................. 6-17
Power Supply ................................ 6-18
Color Deflection Board ...................... 6-19
Color CRT ................................... 6-21
Chapter 7 Adjustments
Monochrome CRT ............................... 7-1
Display out of Focus ........................ 7-3
Display too D i m .............................. 7-3
Display Rolls ................................ 7-4
Display too Short/Long ....................... 7-4
Display Not L i ne a r ........................... 7-5
Display too Wide/Narrow ...................... 7-5
Display Tilted ............................... 7-5
Character Field Size
......................... 7-6
Color CRT ..................................... 7-6
Horizontal Deflection ......................... 7-8
iv

Oscillator Alignment .......................... 7-8
Picture Width ................................ 7-9
Vertical Deflection ........................... 7-10
Video ...........................................7-11
Cutoff Adjustment ............................ 7-11
Whiteness ......................................7-12
Sub-Brightness ............................... 7-12
Focus ..........................................7-13
Convergence .................................. 7-13
Convergence Adjustments ...................... 7-13
Adjustments for Videotex Monitor 008-0072370 .. 7-15
Adjustments for Videotex Monitor 008-0072196 .. 7-18
Chapter 8 Strapping Information
Main Processor Board ........................... 8-1
Configuration Switches ......................... 8-1
Jumper Settings ................................ 8-5
Alternate Main Processor Board ................ 8-1
Switch Settings ............................... 8-2
Jumper Settings ................................. 8-6
Early-type Main Processor Eoard
............... 8-7
Switch Configurations of Early-type MPB ....... 8-8
Switch Configurations of PCBs
.................. 8-10
Memory Expansion Board ........................ 8-10
Alpha Display Adapter ........................ 8-1 1
Graphic Controller Boards ..................... 8-12
In-House DLC Adapter ......................... 8-13
Videotex Adapter Board ....................... 8-14
Flexible Disk Controller Board 1.2 MB .......... 8-16
Hard Disk Controller Boards .................. 8-17
Flexible Disk Drive Jumpers .................... 8-20
Appendix A Layouts and Schematics
v

Chapter 1
System Overview
NCR PERSONAL COMPUTER HARDWARE
The NCR Personal Computer consists of a main Display
Unit and a Keyboard. The computer is available in
different models, and has a variety of options that
can be added to each model. Expansion boards from
non-NCR ("third party") manufacturers can be used
with the NCR Personal Compter, as well as expansion
boards offered by NCR.
DISPLAY UNIT
The standard Display Unit consists of the following
parts:
o Cabinet
o Power Supply
o 1 or 2 flexible disk drive(s) or one flexible disk
drive and one hard disk drive
o 12-inch monochrome CRT display or 12-inch color
CRT display
o Processor Board with:
o 8088 Microprocessor
o 256 KB Random Access Memory (RAM)
o 16K Read Only Memory (ROM)
o RS-232-C Serial Interface
o Centronics Parallel Interface (for printer)
1-1

SYSTEM OVERVIEW
o Plug-in board option expansion slots
o Fixed disk drive controller plug-in board if
the unit includes a fixed disk.
o Video controller plug-in board.
A block diagram of the NCR Personal Computer Hardware
is shown in Figure 1-1.
Figure 1-1 Hardware Block Diagram
The Main Processor Board and any option boards are
1-2