NEC VERSA S User manual

First Printing — June 1994
Copyright 1994 Copyright 1994
NEC Technologies, Inc. NEC Corporation
1414 Massachusetts Avenue 7-1 Shiba 5-Chome, Minato-Ku
Boxborough, MA 01719 Tokyo 108-01, Japan
All Rights Reserved All Rights Reserved
PROPRIETARY NOTICE AND LIABILITY DISCLAIMER
The information disclosed in this document, including all designs and related materials, is
the valuable property of NEC Corporation (NEC) and/or its licensors. NEC and/or its licen-
sors, as appropriate, reserve all patent, copyright and other proprietary rights to this docu-
ment, including all design, manufacturing, reproduction, use, and sales rights thereto, except
to the extent said rights are expressly granted to others.
The NEC product(s) discussed in this document are warranted in accordance with the terms
of the Warranty Statement accompanying each product. However, actual performance of
each such product is dependent upon factors such as system configuration, customer data,
and operator control. Since implementation by customers of each product may vary, the
suitability of specific product configurations and applications must be determined by the
customer and is not warranted by NEC.
To allow for design and specification improvements, the information in this document is
subject to change at any time, without notice. Reproduction of this document or portions
thereof without prior written approval of NEC is prohibited.
Versa and FastFacts are U.S. trademarks of NEC Technologies, Inc.
All other product, brand, or trade names used in this publication are the trademarks or registered
trademarks of their respective trademark owners.

xi
Preface
This service and reference manual contains the technical information necessary to set up,
maintain, troubleshoot, and repair the Versa S series sub-notebooks. It also provides hard-
ware and interface information for users who need an overview of the computer system de-
sign. The manual is written for NEC-trained customer engineers, system analysts, service
center personnel, and dealers.
The manual is organized as follows:
Section 1, Technical Information, provides an overview of the computer features, hard-
ware design, interface ports and internal devices.
Section 2, Setup and Operation, takes the user from unpacking to setup and operation.
Included is a description of the operating controls, System Configuration Utility, and system
password.
Section 3, Power Management, describes how to use power management options to con-
serve energy and save battery power.
Section 4, Options, provides the user with installation information for options such as
PCMCIA cards, memory upgrade, hard disk upgrade, and connecting external devices.
Section 5, Troubleshooting and Repair, includes a list of NEC service information and
telephone numbers that provide access to the NEC Bulletin Board System (BBS), Fast-
Facts, and Technical Information Bulletins. Included are desktop disassembly and reassem-
bly procedures along with an illustrated parts breakdown. NEC service and spare parts
ordering information is also provided.
Appendix A, Connector Pin Assignments, provides a list of the system board connector
pin assignments.
An Index is included for convenience.

xiii
Abbreviations
Aampere
AC alternating current
AT advanced technology
(IBM PC)
BBS Bulletin Board System
BCD binary-coded decimal
BCU BIOS Customized Utility
BIOS basic input/output system
bit binary digit
BUU BIOS Upgrade Utility
bpi bits per inch
bps bits per second
Ccapacitance
Ccentigrade
Cache high-speed buffer storage
CAM constantly addressable memory
CAS column address strobe
CD-ROM compact disk-ROM
CG character generator
CGA Color Graphics Adapter
CGB Color Graphics Board
CH channel
clk clock
cm centimeter
CMOS complementary metal oxide
semiconductor
COM communication
CONT contrast
CPGA ceramic pin grid array
CPU central processing unit
DAC digital-to-analog converter
DACK DMA acknowledge
DC direct current
DIP dual in-line package
DLAB Divisor Latch Address bit
DMA direct memory access
DMAC DMA controller
DOS disk operating system
DRAM dynamic RAM
DTE data terminal equipment
ECC error checking and correction
EGA Enhanced Graphics Adapter
EPROM erasable and programmable
ROM
EVGA Enhanced Video Graphics
Array
FFahrenheit
FCC Federal Communications
Commission
FG frame ground
FM frequency modulation
FRU field-replaceable unit
GB gigabyte
GND ground
HEX hexadecimal
HGA Hercules Graphics Adapter
Hz hertz
IC integrated circuit
ID identification
IDE intelligent device electronics
IDTR interrupt descriptor table
register
in. inch
INTA interrupt acknowledge
IPB illustrated parts breakdown
IRR Interrupt Request register
ISA Industry Standard Architecture
ISR In Service register
I/O input/output
IPC integrated peripheral controller
ips inches per second
IRQ interrupt request

xiv Abbreviations
Kkilo (1024)
kkilo (1000)
KB kilobyte
kg kilogram
kHz kilohertz
lb pound
LED light-emitting diode
LSB least-significant bit
LSI large-scale integration
Mmega
mA milliamps
max maximum
MB megabyte
MDA Monochrome Display Adapter
MFM modified frequency modulation
MHz megahertz
mm millimeter
ms millisecond
MSB most-significant bit
NASC National Authorized Service
Center
NC not connected
NMI Non-maskable Interrupt
ns nanosecond
NSRC National Service Response
Center
PAL programmable array logic
PC personal computer
PCB printed circuit board
PFP plastic flat package
PIO parallel input/output
pixel picture element
PLCC plastic lead chip carrier
PLL phase lock loop
p-p peak-to-peak
PPI programmable peripheral
interface
PROM programmable ROM
QFP quad flat pack
RAM random-access memory
RAMDAC RAM digital-to-analog
RAS row address strobe
RGB red green blue
RGBI red green blue intensity
ROM read-only memory
rpm revolutions per minute
Rread
RTC real-time clock
R/W read/write
Sslave
SG signal ground
SIMM single inline memory module
SVGA Super Video Graphics Array
SW switch
TAC Technical Assistance Center
TSC Technical Support Center
TTL transistor/transistor logic
tpi tracks per inch
Vvolt
Vdc volts, direct current
VESA video electronics standards
association
VGA Video Graphics Array
VRAM virtual RAM
Wwatt
Wwrite

v
Contents
Page
Preface........................................................................................................................ xi
Abbreviations .............................................................................................................. xiii
Section 1 Technical Information
Hardware Overview..................................................................................................... 1-2
Liquid Crystal Display (LCD)............................................................................... 1-2
Keyboard.............................................................................................................. 1-3
Versa SurePoint.................................................................................................... 1-3
LED Status Bar.................................................................................................... 1-3
Battery ................................................................................................................. 1-4
System Board....................................................................................................... 1-5
CPU ............................................................................................................. 1-5
Memory........................................................................................................ 1-5
Video Controller........................................................................................... 1-6
Input/Output Controller................................................................................ 1-7
Keyboard Controller..................................................................................... 1-8
PCMCIA Controller (CL-PD6720)............................................................... 1-8
I/O Addressing ............................................................................................. 1-8
Interrupt Controller ...................................................................................... 1-9
Power Management Overview.............................................................................. 1-10
Specifications .............................................................................................................. 1-11
Section 2 Setup and Operation
Unpacking the System ................................................................................................. 2-1
Setup........................................................................................................................... 2-1
Replacing a Battery Pack...................................................................................... 2-3
Operating Controls...................................................................................................... 2-5
LED Status Bar.................................................................................................... 2-5
SurePoint and Selection Buttons........................................................................... 2-7
Fn Key.................................................................................................................. 2-7
Reset Button......................................................................................................... 2-8
Power-on Self-Test (Post)........................................................................................... 2-8
System Configuration Utility........................................................................................ 2-9
Accessing the SCU............................................................................................... 2-9

vi Contents
Using the SCU...................................................................................................... 2-10
SCU Menu Options .............................................................................................. 2-10
Standard....................................................................................................... 2-10
Preferences................................................................................................... 2-12
VGA............................................................................................................. 2-14
Memory........................................................................................................ 2-14
Power Management...................................................................................... 2-14
Default Setup................................................................................................ 2-14
Exit .............................................................................................................. 2-15
Section 3 Power Management
Power Management Utility .......................................................................................... 3-1
Accessing the Power Management Utility ............................................................. 3-1
Menu Options....................................................................................................... 3-3
Controls........................................................................................................ 3-3
System Options............................................................................................. 3-4
Device Setup ................................................................................................ 3-5
Default Setup................................................................................................ 3-6
Exit .............................................................................................................. 3-6
APM Program............................................................................................................. 3-6
Hardware Power Management.............................................................................. 3-7
System Power Management.................................................................................. 3-7
Device Status........................................................................................................ 3-8
Extending Battery Life................................................................................................. 3-9
Section 4 Options
PCMCIA Cards........................................................................................................... 4-1
Modem Card Connection...................................................................................... 4-2
External Devices.......................................................................................................... 4-5
Parallel Devices .................................................................................................... 4-5
Serial Devices....................................................................................................... 4-6
Keyboard.............................................................................................................. 4-6
Mouse.................................................................................................................. 4-7
Monitor................................................................................................................ 4-8
Internal Upgrades........................................................................................................ 4-9
Moving the Keyboard........................................................................................... 4-10
Upgrading Memory .............................................................................................. 4-12

Contents vii
Upgrading the Hard Disk...................................................................................... 4-13
Replacing the Keyboard........................................................................................ 4-15
Running Setup...................................................................................................... 4-16
Memory Modules ......................................................................................... 4-16
Hard Disk..................................................................................................... 4-17
Section 5 Troubleshooting and Repair
Maintenance................................................................................................................ 5-2
Cleaning ............................................................................................................... 5-2
Routine Checks .................................................................................................... 5-2
CMOS Clear Switch.................................................................................................... 5-3
Troubleshooting .......................................................................................................... 5-4
Problem Checklist................................................................................................. 5-4
Diagnosing and Solving Problems......................................................................... 5-4
Error Messages............................................................................................. 5-6
Beep Codes .................................................................................................. 5-8
Disassembly and Reassembly ....................................................................................... 5-8
Removing the Battery Pack................................................................................... 5-9
Removing the Keyboard ....................................................................................... 5-10
Removing the Memory Module............................................................................. 5-13
Removing the Hard Disk....................................................................................... 5-14
Removing the System Cover and LCD Assembly.................................................. 5-15
Removing the CMOS or Bridge Battery................................................................ 5-17
Removing the Inverter Circuit Board .................................................................... 5-18
Removing the System Board................................................................................. 5-19
Removing the LED Circuit Board......................................................................... 5-20
Removing the LCD Cover .................................................................................... 5-21
Separating the LCD Assembly from the System Cover.......................................... 5-22
Illustrated Parts Breakdown......................................................................................... 5-23

viii Contents
Figures
Figure Title Page
1-1 Versa S Components .....................................................................................1-1
1-2 Versa S Series (Rear View) ...........................................................................1-2
1-3 LED Status Bar.............................................................................................1-3
2-1 Opening the LCD Panel.................................................................................2-1
2-2 Attaching the AC Adapter..............................................................................2-2
2-3 Connecting the Diskette Drive .......................................................................2-2
2-4 Turning on the Versa S..................................................................................2-3
2-5 Removing the Battery Pack............................................................................2-3
2-6 Locating the Tabs and Grooves......................................................................2-4
2-7 Inserting the Battery Pack..............................................................................2-4
2-8 Control and Button Locations........................................................................2-5
2-9 LED Status Bar.............................................................................................2-5
2-10 SurePoint and Selection Buttons....................................................................2-7
2-11 SCU Main Menu............................................................................................2-9
3-1 Power Management Menu.............................................................................3-2
4-1 PCMCIA Card Slots......................................................................................4-2
4-2 Installing the Modem Card.............................................................................4-3
4-3 Connecting the Adapter.................................................................................4-3
4-4 Telephone Line Connection ...........................................................................4-4
4-5 Modem and Telephone Connection................................................................4-5
4-6 Connecting a Parallel Device..........................................................................4-5
4-7 Attaching a Serial Device...............................................................................4-6
4-8 Attaching the External Keyboard ...................................................................4-7
4-9 Connecting the Mouse...................................................................................4-8
4-10 Connecting the External Monitor...................................................................4-9
4-11 Locating the Retainer.....................................................................................4-10
4-12 Removing the Retainer...................................................................................4-10
4-13 Lifting the Keyboard......................................................................................4-11
4-14 Leaning the Keyboard against the LCD..........................................................4-11
4-15 Locating the Memory Module Socket............................................................4-12
4-16 Installing the Module.....................................................................................4-13

Contents ix
4-17 Locating the Hard Disk..................................................................................4-13
4-18 Removing the Screw......................................................................................4-14
4-19 Removing the Hard Disk................................................................................4-14
4-20 Installing the Hard Disk .................................................................................4-15
4-21 Positioning the Keyboard...............................................................................4-15
4-22 Inserting the Retainer.....................................................................................4-16
5-1 Locating the CMOS Clear Switch..................................................................5-3
5-2 Removing the Battery Pack............................................................................5-10
5-3 Locating the Plastic Retainer..........................................................................5-10
5-4 Removing the Retainer...................................................................................5-11
5-5 Lifting the Keyboard......................................................................................5-11
5-6 Leaning the Keyboard Against the LCD.........................................................5-12
5-7 Disconnecting the Keyboard Cables...............................................................5-12
5-8 Locating the Memory Module........................................................................5-13
5-9 Removing the Memory Module......................................................................5-13
5-10 Locating the Hard Disk..................................................................................5-14
5-11 Removing the Screw......................................................................................5-14
5-12 Removing the Hard Disk................................................................................5-15
5-13 Removing System Cover Screw (Rear)..........................................................5-15
5-14 Removing System Cover Screws (Bottom) ....................................................5-16
5-15 Removing System Cover Screws (Top)..........................................................5-16
5-16 Removing the System Cover and LCD Assembly...........................................5-17
5-17 Removing the CMOS and Bridge Batteries....................................................5-18
5-18 Removing the Inverter Circuit Board .............................................................5-18
5-19 Removing the System Board..........................................................................5-19
5-20 Removing the LED Circuit Board..................................................................5-20
5-21 Removing LCD Cover Screws.......................................................................5-21
5-22 Separating the LCD Assembly and System Cover...........................................5-22
5-23 Versa S Illustrated Parts Breakdown..............................................................5-25

xContents
Tables
Table Title Page
1-1 Versa S Supported Chipsets...........................................................................1-5
1-2 Versa S System Memory Map........................................................................1-6
1-3 Versa S Video Modes....................................................................................1-6
1-4 Parallel Port Addresses and Interrupts............................................................1-7
1-5 Serial Port Addresses and Interrupts ..............................................................1-7
1-6 Versa S I/O Address Map..............................................................................1-8
1-7 Versa S Series Interrupt-Level Assignments...................................................1-10
1-8 Specifications.................................................................................................1-11
3-1 Status of Devices in Auto Suspend Mode.......................................................3-8
3-2 Status of Devices in Power Saving Mode.......................................................3-8
5-1 NEC Service and Information Telephone Numbers ........................................5-1
5-2 Problems and Solutions..................................................................................5-5
5-3 Error Messages..............................................................................................5-7
5-4 Beep Codes ...................................................................................................5-8
5-5 Disassembly...................................................................................................5-8
5-6 Versa S Field-Replaceable Parts List..............................................................5-23
5-7 Documentation..............................................................................................5-24
A-1 Serial Interface Connector .............................................................................A-1
A-2 Parallel Interface Connector...........................................................................A-2
A-3 VGA Interface Connector..............................................................................A-3
A-4 Keyboard/Mouse Connector..........................................................................A-3
A-5 DC Power Connector ....................................................................................A-4
A-6 Diskette Drive Connector ..............................................................................A-4
A-7 Hard Disk Connector.....................................................................................A-5

Contents xi

Section 1
Technical Information
The NEC Versa™ S series sub-notebooks integrate Intel's SL Enhanced 486 microproces-
sor. The systems offer a unique transportable unit in the following models:
nVersa S/50C 486DX2-50 CPU, thin-film-transistor (TFT) color LCD, 4-MB
standard RAM, 8 KB cache RAM, 128-KB ROM, 260-MB hard disk
nVersa S/33C 486SX-33 CPU, TFT color LCD, 4-MB standard RAM, 8 KB
cache RAM, 128-KB ROM, 210-MB hard disk
nVersa S/33D 486SX-33 CPU, double-scan super-twist nematic (DSTN) color
LCD, 4-MB standard RAM, 8 KB cache RAM, 128-KB ROM, 210-MB hard disk
nVersa S/33M 486SX-33 CPU, monochrome LCD, 4-MB standard RAM, 8
KB cache RAM, 128-KB ROM, 210-MB hard disk (125-MB – international
models).
Figure Section 1-1 shows the components on the front and side views of the Versa S.
Figure Section 1-1Versa S Components
The following system upgrades must be completed by authorized customer engineers or an
authorized service center:
nadditional memory (up to 12 MB)
n260-MB hard disk.
System upgrade procedures are described in Section 4, Options.
Reset
Button
Power
Button Slot
PCMCIA Latch
LCD

1-2 Technical Information
HARDWARE OVERVIEW
The base unit includes a monochrome or color LCD panel, a 210- or 260-MB hard disk, an
external 1.44-MB diskette drive, a battery pack, and a PS/2 compatible 80-key keyboard. A
81-key keyboard is used for U.K. and Germany.
One memory card slot is available for the addition of a 4- or 8-MB memory card. Two Per-
sonal Computer Memory Card International Association (PCMCIA) card slots, supported
by the Cirrus Logic CL-PD6720 PCMCIA chip set, allow for the addition of either two
Type 2 PCMCIA cards or one Type 3 PCMCIA card.
Figure Section 1-2 shows the I/O interface ports on the system's rear panel. These include
one combined 6-pin PS/2-style keyboard and mouse port, one 15-pin Super VGA port, one
9-pin (RS-232C) serial port, one 25-pin enhanced printer (parallel) port, and one 3-pin
power connector port.
Figure Section 1-2Versa S Series (Rear View)
Liquid Crystal Display (LCD)
The Versa S comes with one of three different LCD panels. Each panel provides a 9.5-inch
viewing area.
nThe thin-film transistor (TFT) color LCD has a 640 x 480 resolution, is backlit,
and supports up to 4096 colors.
nThe Dualscan Super-Twisted Nematic (DSTN) color LCD has a 640 x 480 reso-
lution, is backlit, and supports up to 256 colors.
nThe DSTN monochrome LCD (outside of the U.S. only) has a 640 x 480 resolu-
tion, is backlit, and supports 64 shades of gray.
A VGA port on the system's rear panel allows the user to connect an optional monochrome
or color external display to the system. The computer supports the LCD and external dis-
play simultaneously when using a resolution of 640 x 480 or lower.
Power
Port
Port
Mouse
Keyboard/
Parallel
Port
Port
Drive
Diskette
VGA
Monitor
Port Port
Serial

Technical Information 1-3
Power-saving features for controlling the LCD's backlighting include the ROM-based hot
key Fn F5, Fn F6, and Auto Setup power management settings. See Section 2, Setup and
Operation, for information on using these settings. In addition, the automatic LCD status
sense feature conserves the backlight. When the LCD is closed, the backlight shuts off,
saving battery power.
Keyboard
The built-in, 80-key keyboard (U.S.) or 81-key keyboard (UK and Germany) uses the stan-
dard QWERTY-key layout. The keyboard provides 12 function keys and 8 cursor control
keys, with an Fn key for ROM-based key functions. The numeric keypad is embedded in the
standard key layout.
Versa SurePoint
The Versa SurePoint™ pointing device performs the functions of a mouse. It is located
between the G, H, and B keys. Pressing the Versa SurePoint in a specific direction moves
the cursor in that direction. The two selection buttons below the keyboard act like the left
and right mouse buttons on a two-button mouse.
The Versa SurePoint is the system's default pointing device unless a PS/2 mouse is installed.
If an external mouse is installed, then the Versa SurePoint is deactivated.
LED Status Bar
The LED status bar contains eight light emitting diodes (LEDs) that light or blink to show
the status of Versa S components. Figure Section 1-3 shows the locations of the LEDs on
the status bar. A description of the LEDs follow.
Figure Section 1-3LED Status Bar
A
Power
Mgmt
Charge
Hard Disk
Drive
Diskette
Drive
Lock
Caps Lock
Scroll
Power
Num
Lock

1-4 Technical Information
nPower LED — lights yellow or green.
When steady green, the computer is running on AC power.
When steady yellow, the computer is running on battery power and battery
power is sufficient.
When blinking yellow, the computer is running on battery power and battery
power is low.
When off, the computer is in Suspend mode or the computer power is off.
nCharge LED — lights orange.
When lit continuously, the battery is charging.
When blinking orange, the battery has malfunctioned.
When off, no battery is installed, the AC adapter is not attached, or the battery
is fully charged.
nPower Management LED — lights green
When lit continuously, Power Management features are enabled.
When blinking, the system is in Suspend mode.
When off, Power Management features are disabled.
nHard Disk LED — lights green when the hard disk is being accessed. Avoid
turning off the Versa S when this LED is lit.
nDiskette Drive LED — lights green when a diskette is being accessed.
nCaps Lock LED — lights green when the Caps Lock is in effect.
nScroll Lock LED — lights green when the scroll lock key is active.
nNum Lock LED — lights green when Num Lock mode is in effect.
Battery
The system uses a nickel metal hydride (NiMH) battery as its transient power source. The
battery pack installs in the compartment at the bottom of the base unit. The battery pack
lasts approximately 2.0 hours under typical operating conditions and recharges in approxi-
mately 1.5 hours. A bridge battery is provided as an emergency backup. It backs up mem-
ory and system status for up to 5 minutes under Suspend mode.

Technical Information 1-5
System Board
The system board is inside the base unit. It contains system components including the CPU,
system memory, and I/O subsystems.
Refer to Table Section 1-1 for a summary of the chipsets supported by the Versa S. For a
list of system board connector descriptions, see Appendix A. System board specifications
are listed in at the end of this section.
Table Section 1-1Versa S Supported Chipsets
Chip Manufacturer Description Technology
i486SX-33 Intel 33 MHz CPU 208-pin QFP*
i486DX2-50 Intel 50 MHz CPU 208-pin QFP*
PT86C368 PicoPower System Controller 208-pin QFP*
FDC37C665 Standard MicroSystem
Corporation Peripheral Controller 100-pin QFP*
28F010 Intel 128-KB Flash ROM 32-pin PLCC**
CL-GD6235 Cirrus Logic VGA Controller 208-pin QFP*
80C51SL Intel Keyboard Controller 44-pin QFP*
CL-PD6720-B Cirrus Logic PCMCIA Controller 208-pin QFP*
*QFP: quad flat package
**PLCC: plastic lead chip carrier
CPU
The CPU is an Intel SL Enhanced i486 chip (DX2-50 or SX-33). The CPU controls im-
portant functions including power management, direct drive bus interface, and memory
management. It has a 32-bit internal data bus and requires an operating voltage of 3.3 volts.
The CPU’s microprocessor has an internal on-chip cache controller with 8-KB cache mem-
ory. The DX2-50's floating point unit (FPU) provides an internal math coprocessor.
Memory
The system board provides 4 MB of standard random access memory (RAM). Optional
memory cards with a value of 4- or 8-MB can be added to increase system memory up to
12 MB.
The system board also provides 128 KB of read-only memory (ROM). The 28F010 flash
ROM contains the system, power management, and video BIOS.

1-6 Technical Information
The Versa S supports system and video BIOS shadowing. When shadowing is enabled (de-
fault settings), the BIOS is copied from ROM to RAM which speeds up system perform-
ance. These settings can be changed in the SCU (see Section 2, Setup and Operation).
Table Section 1-2 shows the system's memory map.
Table Section 1-2Versa S System
Memory Map
Address Function
FFFFF
|
F0000
System BIOS (shadow) (64 KB)
|
E8000 MAXIMIZER (shadow) (32 KB)
|
E0000 Video BIOS (shadow enabled) (32 KB)
|
C8000 ISA space available
|
C0000 Video BIOS (shadow enabled) (32 KB)
Video Controller
The Cirrus CL-GD6235 video controller integrates a 32-bit local bus video. The system
ships with 512 KB VRAM supporting LCD video modes up to 640 x 480 resolution with
256 colors (color model) or 64 shades of gray (monochrome model).
The system provides a 15-pin D-SUB connector to allow connecting an external display to
the system. The system supports external display video modes up to 1024 x 768 with 16
colors or 800 x 600 x 256 color (non-interlaced). System video also supports simultaneous
external display and LCD viewing. Table Section 1-3 shows the supported Versa S video
modes.
Table Section 1-3Versa S Video Modes
Mode
(Hex)
Pixel
Resolution
Character
Size
Columns
/Rows
Colors
(K)
Video
Clock
(MHz)
Horizontal
Freq
(kHz)
Vertical
Freq
(Hz)
12 640 x 480 8 x 16 30 x 30 16/256 25.0 31.5 60.0
58/6A * 800 x 600 8 x 16 100 x 37 16/256 40.0 37.8 60.0
5C * 800 x 600 8 x 16 100 x 37 256/256 40.0 37.9 60.0
5D * 1024 x 768 8 x 16 128 x 48 16 65.0 48.3 60.0

Technical Information 1-7
5F 640 x 480 8 x 16 80 x 30 256/256 25.0 31.5 60.0
NOTE: * External display only.
Input/Output Controller
The FDC37C665 input/output (I/O) controller provides the following interfaces:
nRS-232C serial port
nparallel (printer) port
ndiskette drive
nIDE hard disk.
The user selects between three parallel interface modes using Auto Setup. These include
unidirectional, bidirectional or enhanced. Unidirectional mode sends data output from the
standard ISA port only. Bidirectional mode sends data using the standard ISA port or PS/2
technology. Enhanced mode enables high speed data transmission to occur using either the
unidirectional or bidirectional modes.
Parallel port addresses and interrupts are listed in Table Section 1-4. Pin locations for the
parallel interface are listed in Appendix A.
Table Section 1-4Parallel Port Addresses and Interrupts
Starting I/O Address Interrupt Level
378h (LPT 1) * IRQ07
278h (LPT 2) IRQ05
3BCh (LPT 3) IRQ07
*Default
The serial port consists of a 16450 compatible serial port controller with a programmable
baud rate within 50/115.2 K bps. See Table Section 1-5 for the available addresses and in-
terrupts.
Table Section 1-5Serial Port Addresses and Interrupts
Starting I/O Address Interrupt Level
3F8h (COM 1) * IRQ04
2F8h (COM 2) IRQ03
3E8h (COM 3) IRQ04
2E8h (COM 4) IRQ03

1-8 Technical Information
*Default
Keyboard Controller
The keyboard controller (80C51SL) supports a PS/2-style keyboard, mouse and security
features such as keyboard hot keys and password. Refer to Appendix A for keyboard inter-
face connector pin assignments.
The input clock cycle is 12 MHz. Data transmits between the controller and the keyboard
through a bidirectional serial interface. The controller receives serial data, checks for parity
errors, converts scan codes, and writes the data to the output buffer.
When data is written to the output buffer, the controller generates an interrupt (IRQ01 or
IRQ12) and requests the CPU to receive the data. The controller automatically adds an
even parity bit to the data sent and waits for a response. The device must acknowledge that
the data was successfully received by sending a response to the controller for each byte of
data received.
PCMCIA Controller (CL-PD6720)
The PCMCIA interface uses a standard Exchangeable Card Architecture (ExCA) connector
allowing the user to choose from an array of optional modem or network cards. The con-
troller interfaces with the ISA bus, PCMCIA card socket and configuration registers to
provide:
nmemory address mapping, I/O address mapping
npower management for each PCMCIA card socket, controlled through power and
RESETDRV control registers
nthe elimination of interrupt conflicts using interrupt steering.
I/O Addressing
The CPU works in conjunction with I/O devices using I/O mapping. Refer to Table Section
1-6 for hex addresses.
Table Section 1-6Versa S I/O Address Map
Address (Hex) I/O Device Name
000-00F DMA Controller 1
020-03F Interrupt Controller 1
040-043 Timer 1
048-04B Timer 2
060-064 Keyboard Controller

Technical Information 1-9
Table Section 1-6Versa S I/O Address Map
Address (Hex) I/O Device Name
061 NMI Status
070 NMI Mask
070-076 Real-time Clock
081H-083H DMA Page Register
087H DMA Page Register
089H-08BH DMA Page Register
08FH DMA Page Register
092H Port 92
0C0H-0CEH DMA Channel
0D0H-0DEH DMA Controller 2
0102H Parallel Port Configuration
0278H-027AH LPT2
02F8H-02FFH Serial Controller Port B
0372H-0377H Diskette Drive Controller
0378H-037AH LPT1
03BCH-03BEH LPT3
03F0H-03F5H Diskette Drive Controller Port Status
03F8H-03FFH Serial Controller Port A
0461H Port 461 EISA mode
0C00H Extended System Port 1
0C01H Extended System Port 2
0C02H Extended System Port 3
0C03H Extended System Port 4
0C10H Extended System Port 6
03E0-03E1 PCMCIA
Interrupt Controller
The interrupt controller operates as an interrupt manager for the CPU. The controller re-
ceives requests from peripherals and issues interrupt requests to the CPU. Interrupt-level
assignments 0 through 15 are listed in Table Section 1-7, in order of decreasing priority.