Trimond HU430, Hurricane User Guide

User Guide

HU430 (Hurricane) NLX Motherboard

124575UG Revision 2

13-3-98

This document is the exclusive property of Mitsubishi Electric PC Division. It shall not be copied nor it's contents
communicated or reproduced in any form and for any purpose without specific authority in writing from Mitsubishi
Electric PC Division.

HU430 NLX Motherboard User Guide 124575UG Revision 2

Contents

1 OVERVIEW...................................................................................................................................3

1.1 M

1.2 C

OTHERBOARD FEATURES

ONFIGURATION OPTIONS

...........................................................................................................3

............................................................................................................4

1.2.1 Build-time............................................................................................................................4

1.2.2 User Configurable...............................................................................................................4

LOCK DIAGRAM

1.3 B

.........................................................................................................................5

2 ELECTRONICS.............................................................................................................................6

ROCESSOR

2.1 P

2.2 C

2.3 L

2.4 M

ORE LOGIC

EVEL

EMORY

..................................................................................................................................6

.................................................................................................................................6

ACHE

2 C

............................................................................................................................7

......................................................................................................................................7

2.4.1 Main Memory......................................................................................................................7

2.4.2 BIOS...................................................................................................................... ..............7

IDEO

2.5 V

2.6 A

2.7 S

...........................................................................................................................................7

UDIO

..........................................................................................................................................8

TANDARD

I/O .............................................................................................................................8

2.7.1 Keyboard and Mouse..........................................................................................................9

2.7.2 Floppy Disk Interface..........................................................................................................9

2.7.3 Serial Ports .........................................................................................................................9

2.7.4 Parallel Port .......................................................................................................................9

DDITIONAL

2.8 A

I/O...........................................................................................................................9

2.8.1 IDE Disk Controller............................................................................................................9

2.8.2 Universal Serial Bus (USB) ..............................................................................................10

2.8.3 System Management Bus (SMBus)....................................................................................10

2.9 M

OTHERBOARD POWER

..............................................................................................................10

2.9.1 Regulators.........................................................................................................................10

2.9.2 Battery...............................................................................................................................10

2.10 P

OWER MANAGEMENT

...........................................................................................................11

2.10.1 Global Power States.....................................................................................................11

2.10.2 Power-on Control.........................................................................................................11

2.11 E

XPANSION SLOTS

.................................................................................................................11

2.11.1 Industry Standard Architecture (ISA)...........................................................................11

2.11.2 Peripheral Component Interconnect (PCI) ..................................................................12

2.12 B

US RESOURCE UTILISATION

.................................................................................................12

2.12.1 ISA DMA Channels.......................................................................................................12

2.12.2 ISA Interrupts ...............................................................................................................12

2.12.3 PCI Interrupts...............................................................................................................13

2.12.4 PCI Device Selection....................................................................................................13

2.12.5 PCI Arbitration.............................................................................................................13

3 ELECTRICAL, MECHANICAL, THERMAL.........................................................................13

OWER REQUIREMENTS

3.1 P

..............................................................................................................13

3.2 PCB............................................................................................................................................13

HERMAL

3.3 T

...................................................................................................................................14

APPENDIX A. JUMPERS AND SWITCHES....................................................................................15

APPENDIX B. CONNECTOR ASSIGNMENTS ..............................................................................17

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HU430 NLX Motherboard User Guide 124575UG Revision 2

1 Overview

The HU430 motherboard is an NLX form factor socket 7 design, with a local bus speed of 60
or 66MHz. The design is based around the Intel 430TX chipset. The board was designed to be
compliant with the NLX specification 1.2 and must be used with an NLX riser that also
conforms to this specification.

1.1 Motherboard Features

Form factor NLX, 9.0" wide x 10.0" long
Processors Socket 7 - P54C, P55C, K6, 60/66MHz bus speed
Power regulation

Core logic Intel 430TX with PIIX4E ISA bridge
Cache 256KB or 512KB on-board L2
Memory – RAM 2 DIMMs for 64-bit unbuffered SDRAM (or EDO)
Memory - Flash ROM 2Mb: BIOS/Setup, USB, DMI, 120FD
Buses 3 bus master PCI slots and ISA
VGA ATI VT3 (VT-B) part standard, 3D-RAGE II+ compatible, 1MB

Audio – controller Business audio only, Crystal CS4236B
Audio – features MIDI/joystick header
Audio – output Mono internal speaker, ‘PHONES OUT, MIC IN jacks on

Hard Disk & CD-ROM Dual ATA33 (UltraDMA/33)
Floppy Disk Standard 3.5”, 5.25” & tape drives. Support for 120MB via IDE
Parallel Port IEEE 1284 (ECP & standard)
Serial Ports 2x 16550s: 9-way ‘D’ COM1, COM2
USB Dual USB connector; optionally one channel can be routed to the

Keyboard & Mouse Dual-stacked PS/2 style keyboard/mouse connectors
Security BIOS branding
IR I/O IR routed to NLX riser, but not IRDA control signals
Power Management Uses SMM. IRQ wake-up. Magic Packet & PCI PME# supported
Cooling NLX fan signal and CPU fan switched by GPIO port in standby,

System Management DMI instrumentation chip LM78 as optional fit
Plug & Play PC97 compliant
Battery back-up On-board lithium coin cell with 5 years life
PCB 9.0" wide by 10.0" long, all top-side components

Adjustable processor core voltage regulator 2.1V to 3.6V, optional
3V3 regulator for 4 o/p PSUs

40ns EDO upgradeable to 2MB

motherboard rear panel

NLX riser

CPU fansink connector on motheboard

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HU430 NLX Motherboard User Guide 124575UG Revision 2

1.2 Configuration Options

1.2.1 Build-time



L2 cache can be 256KB or 512KB (using 32Kx32 or 64Kx32 parts)



L2 cache can be PBSRAM or MDRAM technology



Flash BIOS ROM can be 2Mb or 4Mb TSOP40



Video controller can be VT3 (VT-B) or 3D-RAGE II+



Video memory (EDO) can be 2MB (4 pieces) soldered down or 1MB (2 pieces) soldered +
2 upgrade sockets



LM78 instrumentation amp populated or de-populated



Audio populated or de-populated

1.2.2 User Configurable



Processor support set by jumpers



Flash BIOS boot block can be unprotected by a jumper (optional fit)



Re-programming of Flash BIOS ROM can be disabled by a jumper (optional fit)



Recovery code can be forced to run by a jumper (optional fit)



Main jumper block - processor bus speed, core multiplier, processor core voltage,
enable/disable video, enable/disable audio

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1.3 Block Diagram

CPU

SOCKET 7

IC13

L
O
R
T
N
O
C

SYSTEM CONTROLLER

430TX MTXC

IC9

PCI - ISA BRIDGE (+RTC)

PIIX4E

IC23

SUPER IO

SMC FD37C67X

IC16

P_D(63:0)
P_A(31:3)

K_TA(7:0)

CACHE 0,1

64K X 32

IC7, 11

MEM_D (63:0)

MEM_MA (11:0)
MEM_CAS# (7:0)
MEM_RAS# (3:0)

IO_DDP (15:0)

CONTR.

IO_DDS (15:0)

CONTR.

I/O CONNECTORS

FLOPPY DRIVES

PARALLEL PORT

DUAL USB

PL15

KEYBOARD

PL9

MOUSE

PL9

SERIAL PORT1

PL3

SERIAL PORT2

PL7

(NLX RISER)

PL3

CONN.

PRIMARY IDE

(NLX RISER)

CONN.

SECONDARY IDE

(NLX RISER)

TAG

SRAM 32K X 8

IC5

MEM BANK 0,1

SDRAM DIMM

MM1,MM2

PCI BUS

ISA BUS

EEPROM

24C16

IC22

VIDEO RAM 0,1,2,3

DRAM_256K16

IC26,29,32,34

(63:0)
D

_M
ID

V

VIDEO DISPLAY CONTR.

ATI 264VT3

SYSTEM MONITOR

LM78

IC24

AUDIO SYSTEM CONTR.

CS4236B

IC28

(9:0)
A

_M
ID

V

IC10

L
O
R
T
N
O
C

IO_LID#,
fan_speed,
power_lines

LM358, IC27

LM4880, IC25

SYSTEM CLOCKS

VID_PIXEL (7:0)

CONTR.

RGB,SYNC.

FLASH BIOS

2Mb
IC15

(19:0)
_SA
ISA

MICROPHONE

PL24 (OR NLX)

HEADPHONE

INT.SPEAKER
(NLX RISER)

ICS9147-03

IC4

PL20

CD IN

PL17

CONN.

VFC/AMC

PL12

CONN.

VGA

PL3

XBUS_XD (7:0)

BUFFER

(15:0)
SD

_
ISA

NLX RISER CONNECTOR

2 Electronics

2.1 Processor

Processor support is for a dual voltage-plane socket 7, for the P54C, P55C and K6. Processor
bus speeds allowed are 60 or 66MHz, and all core multipliers can be set from the main jumper
block PL10. Depending on the processor fitted, the processor bus speed, core multiplier, and
core voltage will have to be correctly set.

2.2 Core Logic

This is the Intel 430TX Pentium PCI chipset which comprises the MTXC North Bridge and
the PIIX4E South Bridge, both in BGA packages:

Board Build Part Step Top Marking

Rev A to D MTXC A1 FW82439TX Q536ES (sample)

FW82439TX Q537ES (sample)

FW82439TX SL238 (prodn.)
Rev D MTXC A2 FW82439TX SL28T (prodn.)
Rev A to D PIIX4 B0 FW82371AB Q534ES (sample)

FW82371AB Q535ES (sample)

FW82371AB SL23P (prodn.)

MTXC North Bridge features



64-bit processor host interface, Pentium family at 60MHz and 66MHz



64-bit DRAM controller, 4MB to 256MB main memory, EDO or SDRAM



L2 cache controller, 256KB or 512KB direct-mapped write-back, caches first 64MB main

memory, PBSRAM or DRAM cache



Synchronous 30MHz/33MHz 32-bit PCI 2.1 bus controller



Data path and buffers, three sets of data buffers



Power management features

PIIX4E South Bridge features



PCI 2.1 interface at 30 & 33MHz



ISA bus controller



Extensive power management features including ACPI compliance



IDE controller, two ports four drives, PIO mode 4 and Ultra 33 synchronous DMA mode



Enhanced DMA controllers, with distributed DMA support



Interrupt controllers, with serial interrupt support



System timers



Dual USB 1.0 port controller, 1.5/12 Mbps



SMBus interface



MC146818A compatible real-time clock with 256 bytes of RAM

HU430 NLX Motherboard User Guide 124575UG Revision 2

2.3 Level 2 Cache

L2 cache controller is a direct-mapped write-back design. Only the first 64MB of main
memory can be cached. It supports standard PBSRAM (15ns cycle time, 8ns clock to output)
or DRAM-based cache

HU430 supports a 256KB cache size (with 2 pcs of 32K x 32) or a 512KB cache size (with 2
pcs of 64K x 32). Optional fit resistors set the appropriate register configuration bits in the
MTXC at power-on. The cache size and type is a build option.

2.4 Memory

2.4.1 Main Memory

There are two DIMM sockets on board. Each socket is 64-bits wide and can accept EDO or
SDRAM modules. These must be unbuffered types and parity/ECC is not supported. 4Mb,
16Mb and 64Mb EDO DRAM types and 16Mb and 64Mb SDRAM types are supported.
Maximum memory per DIMM is 128MB with a maximum motherboard capacity of 256MB.

When populating memory DIMMs, either socket MM1 or MM2 may be used. In a single­DIMM system it will be easier to fit it into MM1 as another DIMM may be added to MM2 in
the future without having to unplug the module in MM1.

2.4.2 BIOS

There is a single TSOP-40 geometry on the motherboard for the Flash EPROM. This is
suitable for 1Mb, 2Mb or 4Mb parts with 5V or 12V programming voltages.

An optional enable/disable jumper, when placed in the disable position, blocks write cycles to
the Flash. This means that commands and data cannot be written to the device. The boards
will normally be shipped with the jumper absent, and the Flash set in the 'program enable'
position.

The optional 'force recover' jumper sets a bit in a GPI port in the PIIX4 and is read by the
BIOS. This is used to force a recovery situation such that data is read from the recovery disk
in the floppy disk drive. Normally, this jumper is not fitted as a recovery situation is auto­detected by the BIOS.

The optional 'unlock boot jumper' enables the boot block to be temporarily unlocked for re­programming.

HU430 has been designed so that the TSOP part can be programmed during ICT.

2.5 Video

Video controller support:



ATI VT-B (“VT3”) for standard builds



ATI 3D-Rage II+, optional build

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HU430 NLX Motherboard User Guide 124575UG Revision 2

The video memory comprises 4 pieces of 256Kx16 40-pin SOJ to give a maximum of 2MB
(64-bits wide). Board builds populated with only 1MB (2 pieces) will have two sockets fitted
to enable the memory to be upgraded to 2MB. The memory type is 40ns EDO DRAM.

An AMC (ATI Media Connector) is also fitted; this is a 40-pin (extended) version of the 26­way VESA feature connector.

2.6 Audio

The audio system is based on the Crystal CS4236B. It is a single chip audio controller
compatible with Sound Blaster, Sound Blaster Pro and the Windows Sound System.

Audio features:



Plug-and-Play ISA bus interface



16-bit address decode support



Internal FM Synthesis Support



Dual DMA Support w/FIFOs, full duplex operation



Programmable Power Management



Joystick Port and MPU-401 compatible MIDI interface



6 channel Input Mixer.

The audio circuit’s output stage is a National Semiconductor LM4880 stereo power amplifier
(Boomer family). It drives a single mono internal speaker or a stereo headphone output jack.
The amplifier will produce 600 mW RMS for the internal speaker and approximately 65 mW
RMS per channel for stereo headphones (32 impedance). The stereo headphone output is
derived from the stereo output mixer of the audio controller and the internal speaker's signal
is derived from the audio controller's separate mono output stage. In the Windows mixer
panel, it is necessary to un-mute the 'PC Speaker' output as this controls the audio controller's
mono output.

A microphone input jack is provided with phantom power for electret condenser
microphones. An optional CD-ROM audio connector is provided for connecting the internal
CD-ROM drive's audio output into the motherboard sound system.

There is a 16-way header which provides the MIDI and joystick functionality via an optional­fit 15-way D-type cable assembly.

The audio section can be completely de-populated, leaving the conventional PC-Beep. The
PC beep is always available from the small PCB-mounted speaker if the enable jumper is
present. The output of the audio sub-system is never fed to the PCB-mounted speaker.

If the audio sub-system is not fitted, then the PC beep signal is fed up the NLX riser on the
left channel. If the audio sub-system is fitted then the mono speaker output is fed up the NLX
riser on the left channel.

2.7 Standard I/O

The SMC FDC37C675 combo controller provides standard I/O. This comprises the four
functional blocks below. It is packaged in a 100-pin QFP and is fully PC97 and motherboard
Plug-and-Play compliant. It supports three ISA DMA channels and supports a serial interrupt

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HU430 NLX Motherboard User Guide 124575UG Revision 2

scheme compatible with that of the PIIX4. This allows a wide selection of interrupt channels
for the serial and parallel ports, and the floppy disk controller.

2.7.1 Keyboard and Mouse

This is implemented in an SMC 37C675 device on the motherboard. The keyboard and mouse
controller uses the Phoenix Multikey version 1.40 firmware. PS/2 style keyboard and mouse
ports are provided on the rear panel. This version does not support keyboard/mouse port
swapping.

2.7.2 Floppy Disk Interface

This is implemented in an SMC 37C675 device on the motherboard. Standard 2-mode and 3­mode 3½” drives are supported. The 3-mode drive includes the 1.6MB (unformatted) mode
that is popular in Japan; this requires a special OS device driver that installs the 1.6MB mode
floppy disk drive as another system device.

The floppy disk drive signals are routed from the motherboard to the NLX riser and the
floppy disk drive connector is mounted on the NLX riser.

As per the NLX specification, all floppy disk input signals to the motherboard must be pulled
up on the NLX riser.

2.7.3 Serial Ports

This is implemented in an SMC 37C675 device on the motherboard. There are two standard
COM ports which are wired to two standard 9-way D-type connectors on the rear panel. The
maximum Baud rate is 115K bits per second.

2.7.4 Parallel Port

This is implemented in an SMC 37C675 device on the motherboard. This is EPP 1.7/1.9 and
IEE1284 (ECP) compliant and is compatible with a standard (output only) PC parallel port as
well as a bi-directional (PS/2 style) parallel port. There is a 25-way D-type connector on the
rear panel.

2.8 Additional I/O

2.8.1 IDE Disk Controller

This is integrated into the PIIX4E South Bridge device. Two connectors are provided on the
NLX riser allowing two drives per cable. The system BIOS auto-detects the drives fitted and
sets the best signal timing appropriate for the drives. PIIX4E supports up to PIO mode 4
timing and bus master IDE transfers up to 33MBps (ATA33). The total cable length attached
to each connector must not exceed 12" or signal integrity problems may result.

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2.8.2 Universal Serial Bus (USB)

The controller is integrated into the PIIX4E. Two channels are wired to a dual-stacked USB
connector provided on the rear panel. Optionally, the motherboard may have a single USB
connector on the rear panel with one channel routed to the NLX riser.

2.8.3 System Management Bus (SMBus)

This is a two-wire bi-directional serial bus compatible with I2C. It comprises a bus master
controller for interrogating other devices, and a slave controller enabling it to act as a slave to
other bus masters. Devices that are connected to this bus are:



mai n memory DIM Ms

The video controller I

2

C bus is local to the video controller, AMC connector, and VGA

connector.

2.9 Motherboard Power

2.9.1 Regulators

The board has a switched-mode regulator and optionally, a linear regulator. The switched­mode regulator provides the power for the processor core, and also powers the processor I/O
in the case of a non-MMX Pentium. The 3V3 power for the rest of the motherboard is
supplied either by an optional-fit on-board linear regulator or by the NLX power supply fed
via the NLX riser.

Warnings: if the optional-fit linear regulator is fitted on the motherboard then the user must
ensure that:



3V3 is not supplied to the motherboard from an NLX PSU via the NLX riser



No peripheral or card on the riser uses the motherboard-generated 3V3

As the switched-mode regulator always supplies the CPU core, the voltage is selectable on the
main jumper block to cater for different processor core voltages (the motherboard cannot
detect this automatically).

2.9.2 Battery

An IEC-type CR2032 3V lithium coin cell and holder are fitted to the board. Cell capacities in
the range 170mAh to 210mAh are acceptable. This cell typically provides battery backup of
the RTC for five years. The battery can be replaced by the user - the clip needs to be prised
back with a small screwdriver and the battery is lifted up by spring pressure.

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HU430 NLX Motherboard User Guide 124575UG Revision 2

2.10 Power Management

2.10.1 Global Power States

The ACPI global power states are summarised in the table below. The last three columns
indicate the colour of a tri-colour LED when the red anode is connected to the 'power LED'
signal from the NLX connector. The 'power LED' signal is controlled by the motherboard.

System power

state

MECH. OFF

AC input PSU main

o/p rails

CPU Green

anode

Red

anode

disconnected off off off off off
(G3)
SOFT-OFF (G2) connected off off off on or off

(build)
SLEEPING
(G1/S1)
WORKING (G0) connected on full speed or

connected on on: clock

stopped

clock

on on or off

(s/w)

on on or off

(s/w)

throttling

2.10.2 Power-on Control

On HU430 a GPO port is used to control the state after an AC reconnect, regardless of how
the machine was powered off:

GPO27 Action

Low machine powers-up in SOFT-OFF and waits for a power button press

before going into WORKING state

High machine powers straight into WORKING state

F/P

LED

red or

off

orange

or green

orange

or green

The GPO port bit is set by the BIOS during each power-on sequence to determine the action
to be taken on the next AC reconnect. This setting is retained by a battery-backed latch. If the
battery is replaced then the board always waits for a power button press before going into the
WORKING state; thereafter the board powers-up immediately upon AC reconnect unless the
BIOS sets the GPO low.

2.11 Expansion Slots

The ISA and PCI expansion slots are located on the riser card. The ISA and PCI signals are
routed through an edge connector on one edge of the board which mates with the NLX riser.

As per the NLX specification, the motherboard requires that the PCI signals are correctly
terminated and pulled up on the NLX riser for the motherboard to operate properly.

2.11.1 Industry Standard Architecture (ISA)

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The PIIX4E can support up to 5 ISA slots on the riser. There are an additional two ISA
‘loads’ used on the motherboard: the audio and super i/o controllers.

2.11.2 Peripheral Component Interconnect (PCI)

The motherboard can support up to 3 bus master PCI slots on the NLX riser.

2.12 Bus Resource Utilisation

2.12.1 ISA DMA Channels

DMA Data

Width

0
1
2
3
4
5
6
7

8-bit
8-bit Audio (8-bit)
8-bit Floppy disk controller
8-bit ECP parallel port

- DMAC daisy chain
16-bit
16-bit
16-bit

Usual Assignment Audio

option
option option

option option

Combo

option

Shaded areas indicate DMA channels not normally available on the ISA bus

2.12.2 ISA Interrupts

IRQ Usual Assignment

0 Timer 0
1 Keyboard
2 PIC daisy chain
3 Serial port 2
4 Serial port 1
5Audio
6 Floppy disk controller
7 Parallel port
8 Real-time clock
9Video
10
11
12 Mouse
13 Co-processor
14 Primary IDE
15 Secondar y IDE

Shaded areas indicate IRQs not normally available on the ISA bus

Audio Combo

option
option
option
option

option option

option

option option

option

option option

option
option option
option option

option

option
option option

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HU430 NLX Motherboard User Guide 124575UG Revision 2

2.12.3 PCI Interrupts

Channel Device

INTA# Slots
INTB# Slots
INTC# Slots
INTD# Video & slots

2.12.4 PCI Device Selection

Dev No IDSEL Device Function No Function

0 AD(11) MTXC
4 AD(15) VGA
7 AD(18) PIIX4E 0 PCI-ISA bridge
“ “ “ 1 IDE interface
“ “ “ 2 USB interface
“ “ “ 3 Power management
16 AD(27) Slot 3
18 AD(29) Slot 2
20 AD(31) Slot 1
Slot resource depends on NLX riser conforming to NLX specification

2.12.5 PCI Arbitration

Channel Device

PHOLD# PIIX4E
0VGA
1 Slot 1
2 Slot 2
3 Slot 3

3 Electrical, Mechanical, Thermal

3.1 Power Requirements

TBD

3.2 PCB

The PCB is a four-layer design measuring W9.0” x L10.0”. It is designed to be NLX
compatible. The following table shows a size comparison with current MEPCD

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HU430 NLX Motherboard User Guide 124575UG Revision 2

motherboards. The 'width' dimension is the edge adjacent to the system rear panel which
contains the I/O connectors:

Length Width Comments

Standard LPX 13.0” 9.0”
Spitfire 7.6” 9.0” Small LPX
HU430 10.0" 9.0" Small NLX

3.3 Thermal

The processor site needs to dissipate up to 28.3W. This will accommodate the 233MHz

0.35µm (3.2V) version of K6. The case temperature of Pentium, Pentium MMX or K6
processors must not exceed 70ºC.

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Appendix A. Jumpers And Switches

Main Jumper Block, PL10

BF1 and BF0 set the processor bus/core multiplier ratio on P54C and P55C processors, and
BF2 is present to support the K6. The FS jumper selects a processor bus speed of 60 or 66
MHz.

The VGA jumper enables/disables the on-board VGA controller as follows:

VGA = IN Enable on-board VGA controller
VGA = OUT Disable on-board VGA

controller

The AUDIO jumper enables/disables the on-board audio (if fitted) as follows:

AUD = IN Enable on-board audio
AUD = OUT Disable on-board audio

Note that the BIOS auto-detects a video card plugged into an expansion slot and disables the
on-board video. The VGA jumper provided disables the on-board VGA controller in
hardware in case there is a problem with the auto-disable function.

The PW3-0 jumpers select the value of the processor core voltage. This is necessary as P54C,
P55C and K6 processors require different core voltages. The board cannot automatically
detect the core voltage that is required by the processor and so this must be set manually.

The table below shows supported CPUs with their configuration jumper settings; note that the
presence of any processor type or speed in the table does not imply that it is or will be
available:

CPU Core/bus

speeds

P54C 90/60 MHz 3/2 30/7.5 MHz OUT 1 1 IN IN IN IN IN 3.5
P54C 100/66 MHz 3/2 33/8.33 MHz OUT 1 1 OU T IN IN IN IN 3.5
P54C 120/60 MHz 2/1 30/7.5 MHz OUT 1 0 IN IN IN IN IN 3.5
P54C 133/66 MHz 2/1 33/8.33 MHz OUT 1 0 OU T IN IN IN IN 3.5
P54C 150/60 MHz 5/2 30/7.5 MHz OUT 0 0 IN IN IN IN IN 3.5
P54C 166/66 MHz 5/2 33/8.33 MHz OUT 0 0 OU T IN IN IN IN 3.5
P55C 166/66 MHz 5/2 33/8.33 MHz OUT 0 0 OUT OUT OUT OUT IN 2.8
K6 166/66 MHz 5/2 33/8.33 MHz OUT 0 0 OUT IN OUT OUT I N 3.2
P54C 200/66 MHz 3/1 33/8.33 MHz OUT 0 1 OU T IN IN IN IN 3.5
P55C 200/66 MHz 3/1 33/8.33 MHz OUT 0 1 OUT OUT OUT OUT IN 2.8
K6 200/66 MHz 3/1 33/8.33 MHz OUT 0 1 OUT IN OUT OUT I N 3.2
P55C 233/66 MHz 7/2 33/8.33 MHz OUT 1 1 OUT OUT OUT OUT IN 2.8
K6 0.35µm 233/66 MHz 7/2 33/8.33 MHz OUT 1 1 OUT IN OUT OUT IN 3.2
K6 0.25µm 233/66 MHz 7/2 33/8.33 MHz OUT 1 1 OUT OUT IN OUT OUT 2.2
K6 0.25µm 266/66 MHz 4/1 33/8.33 MHz IN 1 0 OUT OUT IN OUT OUT 2.2
K6 0.25µm 300/66 MHz 9/2 33/8.33 MHz IN 0 0 OUT OUT IN OUT OUT 2.2

Ratio PCI/ISA bus

speeds

BF2 BF1 BF0 FS Pw2 Pw1 Pw0 Pw3 Cor

V

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HU430 NLX Motherboard User Guide 124575UG Revision 2

g

=1

BF1

=0

=1

BF0

=0

BF2
FS (IN=60MHz, OUT=66MHz)

VGA (IN=enable)
AUDIO (IN=enable)

PW2
PW1
PW0
PW3

PL10 - Confi

uration

=1

BF1

=0

Example - 233MHz P55C

=1

BF0

=0

BF2
FS

VGA
AUDIO

PW2
PW1
PW0
PW3

MMX Power Jumper PL5

Note that these two jumpers must be fitted for a Pentium MMX or K6 processor to function
correctly.

Position Function

1-2, 3-4 P55C MMX or K6

No fit P54C Pentium

Battery Jumper, PL19

Position Function

1-2 Normal operation
2-3 Clear RTC CMOS RAM

Enable On-board Speaker, PL13

Position Function

IN Enable on-board speaker

OUT Disable

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HU430 NLX Motherboard User Guide 124575UG Revision 2

Appendix B. Connector Assignments

NLX Riser Edge Connector

TBA

NLX Supplemental Edge Connector

TBA

USB, PL15

4

1

USB

Port 0

USB

14

Port 1

1+5V
2 DATA­3 DATA+
4 GND

The +5V supply to both connectors is fused with a single 1.1A resettable fuse.

AMC, PL12

Digital ground 1 2 P0
Digital ground 3 4 P1
Digital ground 5 6 P2

EVIDEO/IOW#78P3

ESYNC/IOR# 9 10 P4
EDCLK/RDY 11 12 P5

NC/SAD4/SDA13 14 P6

Digital ground 15 16 P7
Digital ground 17 18 DCLK
Digital ground 19 20 BLANK#/SA

D0

VFSENSE# 21 22 HSYNC/SAD1

NC/SCL 23 24 VSYNC/SAD2

Key pin 25 26 Digital ground
Key pin 27 28 Key pin

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HU430 NLX Motherboard User Guide 124575UG Revision 2

+5V 29 30 SAD3

RESET# 31 32 SAD7

SAD6 33 34 SAD5

RES/SDA 35 36 REV

Analogue gnd 37 38 +12V

AUDRIGHT 39 40 AUDLEFT

VGA, PL3

5

10

15

GND NC BLUE GREEN RED





SCL VSYNC HSYNC SDA NC









GND +5V B RTN G RTN R RTN





















1

11

6









1





11

6

















The +5V supply is fused with a 1.1A resettable fuse.

Keyboard & Mouse, PL9










1CLK
2+5V
3 GND
4 No connect
5 DATA
6 No connect

Parallel Port, PL3

13

25

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1

14

HU430 NLX Motherboard User Guide 124575UG Revision 2

1

STROBE#

PD0

PD1

PD2

PD3

PD4

PD5

PD6

PD7

ACK#

BUSY

PE

SLCT





















































14

















































ALF#

ERROR#

INIT#

SLCTIN#

Ground

Ground

Ground

Ground

Ground

Ground

Ground

Ground

COM1, PL3 And COM2, PL7

1

6

5

9

1 DCD Input Data Carrier Detect
2 RXD Input Receive Data
3 TXD Output Transmit Data
4 DTR Output Data Terminal Ready
5 GND Ground Ground reference pin
6 DSR Input Data Set Ready
7 RTS Output Ready To Send
8 CTS Input Clear To Send
9 R I Input Ring Indicate

MIDI & Joystick Header, PL18

The +5V supply to this connector is fused with a 1.1A resettable fuse.

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HU430 NLX Motherboard User Guide 124575UG Revision 2

+5V 1 2 +5V

J/stick A fire 1 3 4 J/stick B fire 1

J/stick A x-ctrl 5 6 J/stick B x-ctrl

GND 7 8 MIDI out

GND 9 10 J/stick B y-ctrl
J/stick A y-ctrl 11 12 J/stick B fire 2
J/stick A fire 2 13 14 MIDI in

+5V 15 16 Key pin

CPU Fan, PL16

The fan output is fused with a 0.75A resettable fuse. The maximum continuous current that
can be supplied by the motherboard is 150mA.

1 Ground
2 +12V switched
3 Ground

Microphone In, PL20

Shld Frame GND
Ring Bias
Tip Signal input

Headphones Out, PL17

Shld Frame GND
Ring Right output
Tip Left output

CD Audio, PL24

This connector is not always fitted to the motherboard.

1 Reference
2 Left in
3 Reference
4 Right in

Reset, PL14

This connector is not always fitted to the motherboard.

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HU430 NLX Motherboard User Guide 124575UG Revision 2

To cause a reset event to occur, pin 1 must be shorted to ground.

1 Input
2 Ground

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