Acrosser Technology AR-B1540 User manual

AR-B1540/AR-B1541
Half Size Pentium (586)
CPU BOARD
User’ s Guide
Edition: 1.6
Book Number: AR-B1540-02.0802

AR-B1540/AR-B1541 User’s Guide
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Table of Contents
0. PREFACE...............................................................................................................................................................0-3
0.1 COPYRIGHT NOTICE AND DISCLAIMER......................................................................................................................... 0-3
0.2 WELCOME TO THE AR-B1540/AR-B1541 CPU BOARD .................................................................................................. 0-3
0.3 BEFORE YOU USE THIS GUIDE...................................................................................................................................... 0-3
0.4 RETURNING YOUR BOARD FOR SERVICE ....................................................................................................................0-3
0.5 TECHNICAL SUPPORT AND USER COMMENTS............................................................................................................0-3
0.6 ORGANIZATION................................................................................................................................................................ 0-4
0.7 STATIC ELECTRICITY PRECAUTIONS............................................................................................................................0-4
1. OVERVIEW.............................................................................................................................................................1-1
1.1 INTRODUCTION................................................................................................................................................................1-1
1.2 PACKING LIST ..................................................................................................................................................................1-1
1.3 FEATURES........................................................................................................................................................................1-2
2. SYSTEM CONTROLLER .......................................................................................................................................2-1
2.1 DMA CONTROLLER..........................................................................................................................................................2-1
2.2 KEYBOARD CONTROLLER..............................................................................................................................................2-1
2.3 INTERRUPT CONTROLLER..............................................................................................................................................2-2
2.3.1 I/O Port Address Map................................................................................................................................................. 2-3
2.3.2 PCI Bus Assignment (Bus1).......................................................................................................................................2-3
2.3.3 Real-Time Clock and Non-Volatile RAM.....................................................................................................................2-5
2.3.4 Timer..........................................................................................................................................................................2-5
2.4 SERIAL PORT ................................................................................................................................................................... 2-6
2.5 PARALLEL PORT..............................................................................................................................................................2-8
3. SETTING UP THE SYSTEM...................................................................................................................................3-1
3.1 OVERVIEW........................................................................................................................................................................3-1
3.2 SYSTEM SETTING............................................................................................................................................................3-2
3.2.1 Hard Disk (IDE) Connector (CN2)...............................................................................................................................3-2
3.2.2 PC/104 Connector...................................................................................................................................................... 3-3
3.2.3 Keyboard Connector................................................................................................................................................... 3-5
3.2.4 PS/2 Mouse Connector (CN6)....................................................................................................................................3-6
3.2.5 FDD Port Connector (CN4)......................................................................................................................................... 3-6
3.2.6 Parallel Port Connector (CN1).................................................................................................................................... 3-7
3.2.7 Serial Port .................................................................................................................................................................. 3-7
3.2.8 USB Connector (J12) ............................................................................................................................................... 3-10
3.2.9 External Speaker Header (J1).................................................................................................................................. 3-10
3.2.10 Reset Header (J10).............................................................................................................................................. 3-10
3.2.11 LED Header ......................................................................................................................................................... 3-11
3.2.12 Power Connector (J13)......................................................................................................................................... 3-11
3.2.13 CPU Setting ......................................................................................................................................................... 3-12
3.2.14 DRAM Configuration............................................................................................................................................. 3-16
4. CRT/LCD FLAT PANEL DISPLAY ........................................................................................................................4-1
4.1 CRT CONNECTOR (DB1).................................................................................................................................................. 4-1
4.2 LCD FLAT PANEL DISPLAY..............................................................................................................................................4-1
4.2.1 Inverter Board Description..........................................................................................................................................4-2
4.2.2 LCD Connector........................................................................................................................................................... 4-2
5. INSTALLATION......................................................................................................................................................5-1
5.1 OVERVIEW........................................................................................................................................................................5-1
5.2 UTILITY DISKETTE – FOR AR-B1540............................................................................................................................... 5-1
5.2.1 WIN 3.1 Driver............................................................................................................................................................ 5-2
5.2.2 WIN 95 Driver.............................................................................................................................................................5-3
5.2.3 WINNT4.0 Driver........................................................................................................................................................5-3
5.2.4 OS/2 Warp 3.0 Driver.................................................................................................................................................5-4
5.3 UTILITY DISKETTE – FOR AR-B1541............................................................................................................................... 5-4
5.3.1 WIN 3.1 Driver............................................................................................................................................................ 5-5
5.3.2 WIN 95 Driver.............................................................................................................................................................5-5
5.3.3 WINNT 4.0 Driver....................................................................................................................................................... 5-6
5.3.4 OS/2 Warp 3.0 Driver.................................................................................................................................................5-6
5.4 WATCHDOG TIMER..........................................................................................................................................................5-7
5.4.1 Watchdog Timer Setting............................................................................................................................................. 5-8
5.4.2 Watchdog Timer Enabled...........................................................................................................................................5-9
5.4.3 Watchdog Timer Trigger............................................................................................................................................. 5-9
5.4.4 Watchdog Timer Disabled .......................................................................................................................................... 5-9
6. BIOS CONSOLE ....................................................................................................................................................6-1
6.1 BIOS SETUP OVERVIEW..................................................................................................................................................6-1
6.2 STANDARD CMOS SETUP...............................................................................................................................................6-2

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6.3 ADVANCED CMOS SETUP............................................................................................................................................... 6-3
6.4 ADVANCED CHIPSET SETUP.......................................................................................................................................... 6-6
6.5 POWER MANAGEMENT................................................................................................................................................... 6-7
6.6 PCI/PLUG AND PLAY........................................................................................................................................................6-8
6.7 PERIPHERAL SETUP........................................................................................................................................................6-9
6.8 AUTO-DETECT HARD DISKS...........................................................................................................................................6-9
6.9 PASSWORD SETTING.................................................................................................................................................... 6-10
6.9.1 Setting Password ..................................................................................................................................................... 6-10
6.9.2 Password Checking.................................................................................................................................................. 6-10
6.10 LOAD DEFAULT SETTING.......................................................................................................................................... 6-10
6.10.1 Auto Configuration with Optimal Setting................................................................................................................ 6-10
6.10.2 Auto Configuration with Fail Safe Setting.............................................................................................................. 6-10
6.11 BIOS EXIT.................................................................................................................................................................... 6-11
6.11.1 Save Settings and Exit ......................................................................................................................................... 6-11
6.11.2 Exit Without Saving .............................................................................................................................................. 6-11
6.12 BIOS UPDATE............................................................................................................................................................. 6-11
7. SPECIFICATIONS..................................................................................................................................................7-1
8. PLACEMENT & DIMENSIONS ..............................................................................................................................8-1
8.1 PLACEMENT.....................................................................................................................................................................8-1
8.2 DIMENSIONS ....................................................................................................................................................................8-2
9. PROGRAMMING RS-485 & INDEX .......................................................................................................................9-1
9.1 PROGRAMMING RS-485 ..................................................................................................................................................9-1
9.2 INDEX................................................................................................................................................................................9-3

AR-B1540/AR-B1541 User’s Guide
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0.PREFACE
0.1 COPYRIGHT NOTICE AND DISCLAIMER
June 1998
This document is copyrighted, 1998, by Acrosser Technology Co., Ltd. All rights are reserved. No part of this
manual any be reproduced, copied, transcribed, stored in a retrieval system, or translated into any language or
computer language in any form or by any means, such as electronic, mechanical, magnetic, optical, chemical,
manual or other means without the prior written permission of original manufacturer.
Acrosser Technology assumes no representations or warranties with respect to the contents in this manual and
specifically disclaims any implied warranties of merchantability or fitness for any particular purpose. Furthermore,
Acrosser Technology reserves the right to make improvements to the products described in this manual at any
times without notice. Such revisions will be posted on the Internet (WWW.ACROSSER.COM) as soon as possible.
Possession, use, or copying of the software described in this publication is authorized only pursuant to a valid
written license from Acrosser or an authorized sub licensor.
ACKNOWLEDGEMENTS
Acrosser, AMI, IBM PC/AT, SiS, AMD, Cyrix, Intel, Windows 3.1, Windows 95, Windows NT, OS/2 Warp, IDT
Winchip, Chip & Tech Inc. …are registered trademarks.
All other trademarks and registered trademarks are the property of their respective holders.
This document was produced with Adobe Acrobat 3.01.
0.2 WELCOME TO THE AR-B1540/AR-B1541 CPU BOARD
This guide introduces the Acrosser AR-B1540/AR-B1541 CPU board.
The information provided in this manual describes this card’s functions and features. It also helps you start, set up
and operate your AR-B1540/AR-B1541. General system information can also be found in this publication.
0.3 BEFORE YOU USE THIS GUIDE
Please refer to the Chapter 3, “Setting Up the System,” in this guide, if you have not already installed this AR-
B1540/AR-B1541. Check the packing list before you install and make sure the all accessories in the package.
The AR-B1540/AR-B1541 diskettes provide the newest information about the card. Please refer to the
README.DOC file of the enclosed the first utility diskette. It contains the modification, hardware & software
information, and it has updated to product function that may not be mentioned here.
0.4 RETURNING YOUR BOARD FOR SERVICE
If your board requires any services, contact the distributor or sales representative from whom you purchased the
product for service information. If you need to ship your board to us for service, be sure it is packed in a protective
carton. We recommend that you keep the original shipping container for this purpose.
You can help assure efficient servicing for your product by following these guidelines:
1. Include your name, address, telephone, facsimile number and E-mail.
2. A description of the system configuration and/or software at the time is malfunction.
3. A brief description of the problem occurred.
0.5 TECHNICAL SUPPORT AND USER COMMENTS
Users’ comments are always welcome as they assist us in improving the quality of our products and the
readability of our publications. They create a very important part of the input used for product enhancement and
revision.
We may use and distribute any of the information you provide in any way appropriate without incurring any
obligation. You may, of course, continue to use the information you provide.
If you have any suggestions for improving particular sections or if you find any errors on it, please send your
comments to Acrosser Technology Co., Ltd. or your local sales representative and indicate the manual title and
book number.
Internet electronic mail to: [email protected]

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0.6 ORGANIZATION
This information for users covers the following topics (see the Table of Contents for a detailed listing):
! Chapter 1, “Overview”, provides an overview of the system features and packing list.
! Chapter 2, “System Controller”, describes the major structure.
! Chapter 3, “Setting Up the System”, describes how to adjust the jumpers and the connector settings.
! Chapter 4, “CRT/LCD Flat Panel Display”, describes the configuration and installation procedure for
using the LCD and CRT display.
! Chapter 5, “Installation”, describes setup procedures and information on the utility diskette.
! Chapter 6, “BIOS Console”, provides the BIOS options settings.
! Chapter 7, Specifications
! Chapter 8, Placement & Dimensions
! Chapter 9, Programming RS-485 & Index
0.7 STATIC ELECTRICITY PRECAUTIONS
Before removing the board from its anti-static bag, read this section about static electricity precautions.
Static electricity is a constant danger to computer systems. The charge that can build up in your body may be
more than sufficient to damage integrated circuits on any PC board. It is, therefore, important to observe basic
precautions whenever you use or handle computer components. Although areas with humid climates are much
less prone to static build-up, it is always best to safeguard against accidents may result in expensive repairs. The
following measures should generally be sufficient to protect your equipment from static discharge:
1. Touch a grounded metal object to discharge the static electricity in your body (or ideally, wear a
grounded wrist strap).
2. When unpacking and handling the board or other system component, place all materials on an antic
static surface.
3. Be careful not to touch the components on the board, especially the “golden finger” connectors on the
bottom of every board.

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1. OVERVIEW
This chapter provides an overview of your system features and capabilities. The following topics are covered:
! Introduction
! Packing List
! Features
1.1 INTRODUCTION
The AR-B1540/AR-B1541 makes 333MHz, industrial computing a reality. Developed the small size and high
speed systems, this half-size PCI card is excellent for embedded applications due to its stand alone operation,
especially because the AR-B1540 provides an on-board LCD controller.
Great speeds are attained through the PCI-driven IDE controllers. By providing a PCI interface to these two
controllers, the AR-B1540 and AR-B1541 offer an exciting option for engineers involved in high performance
projects. Also, the BIOS is available for the interface peripherals quickly and easily. The AR-B1540 comes with
1MB V-RAM onboard, and the AR-B1541 has 4MB maximum shared memory for VGA display. The system
comes with 512KB synchronous pipe line burst SRAM, one RS-232C and one RS-232C/RS-485 serial port, and
two 72-pin SIMM connectors which can support up to 128MB of DRAM.
The AR-B1540 and AR-B1541 are perfect for medical and telecommunications applications, factory floor networks,
use as an MMI for high-speed processes, or a controller for graphics intensive systems.
1.2 PACKING LIST
The accessories are included with the system. Before you begin installing your AR-B1540/AR-B1541 board, take a
moment to make sure that the following items have been included inside the AR-B1540/AR-B1541 package.
! The quick setup manual
! 1 AR-B1540 or AR-B1541 CPU board
! 1 Hard disk drive adapter cable
! 1 Floppy disk drive adapter cable
! 1 Parallel port adapter cable & 1 RS-232C interface cable mounted on one bracket
! 1 USB device adapter cable
! 4 Software utility CD

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1.3 FEATURES
The system provides a number of special features that enhance its reliability, ensure its availability, and improve its
expansion capabilities, as well as its hardware structure.
! Half size Pentium grade signal board computer
! Supports from 75MHz to 333MHz CPUs (ref. Section CPU Setting of Chapter 3)
! Up to 64MB DRAM system
! Up to 512KB PBSRAM L2 cache system
! On-board CRT and LCD panel display (AR-B1541 doesn’t support the LCD function)
! Supports IDE hard disk drives
! Supports floppy disk drives
! Supports 1 bi-directional parallel port
! Supports 2 serial ports (RS-232C and RS-485)
! PC/AT compatible keyboard and PS/2 mouse interface
! Programmable watchdog timer
! Flash BIOS
! Built-in status LEDs indicator
! Multi-layer PCB for noise reduction
! Dimensions : 122mmX185mm

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2. SYSTEM CONTROLLER
This chapter describes the major structures of the AR-B1540 and AR-B1541 CPU board. The following topics are
covered:
! DMA Controller
! Keyboard Controller
! Interrupt Controller
! Serial Port
! Parallel Port
2.1 DMA CONTROLLER
The equivalent of two 8237A DMA controllers are implemented in the AR-B1540/AR-B1541 board. Each controller
is a four-channel DMA device that will generate the memory addresses and control signals necessary to transfer
information directly between a peripheral device and memory. This allows high speeding information transfer with less
CPU intervention. The two DMA controllers are internally cascaded to provide four DMA channels for transfers to
8-bit peripherals (DMA1) and three channels for transfers to 16-bit peripherals (DMA2). DMA2 channel 0 provides
the cascade interconnection between the two DMA devices, thereby maintaining IBM PC/AT compatibility.
The following is the system information of DMA channels:
DMA Controller 1 DMA Controller 2
Channel 0: Spare Channel 4: Cascade for controller 1
Channel 1: IBM SDLC Channel 5: Spare
Channel 2: Diskette adapter Channel 6: Spare
Channel 3: Spare Channel 7: Spare
Table 2-1 DMA Channel Controller
2.2 KEYBOARD CONTROLLER
The 8042 processor is programmed to support the keyboard serial interface. The keyboard controller receives
serial data from the keyboard, checks its parity, translates scan codes, and presents it to the system as a byte data
in its output buffer. The controller can interrupt the system when data is placed in its output buffer, or wait for the
system to poll its status register to determine when data is available.
Data can be written to the keyboard by writing data to the output buffer of the keyboard controller.
Each byte of data is sent to the keyboard controller in series with an odd parity bit automatically inserted. The
keyboard controller is required to acknowledge all data transmissions. Therefore, another byte of data will not be
sent to keyboard controller until acknowledgment is received for the previous byte sent. The “output buffer full”
interruption may be used for both send and receive routines.

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2.3 INTERRUPT CONTROLLER
The equivalent of two 8259 Programmable Interrupt Controllers (PIC) are included on the AR-B1540 and AR-
B1541 board. They accept requests from peripherals, resolve priorities on pending interrupts in service, issue
interrupt requests to the CPU, and provide vectors which are used as acceptance indices by the CPU to determine
which interrupt service routine to execute.
Following is the system information of interrupt levels:
IRQ8 : Real time clock
IRQ9 : Rerouting to INT 0Ah from hardware IRQ2
IRQ10 : USB (Ref. section Advanced Chipset Setup)
IRQ11 : spare
IRQ12 : spare (PS/2 mouse)
IRQ13 : Math. coprocessor
IRQ14 : Hard disk adapter
IRQ15 : Reserved for watchdog
InInterrupt Level
NMI
CTRL1
IRQ 0
IRQ 1
IRQ 2
IRQ 3
IRQ 4
IRQ 5
IRQ 6
IRQ 7
CTRL2
Parity check
Description
Serial port 2
Serial port 1
Spare
Floppy disk adapter
Parallel port 1
System timer interrupt from timer 8254
Keyboard output buffer full
Figure 2-1 Interrupt Controller

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2.3.1 I/O Port Address Map
Hex Range Device
000-01F DMA controller 1
020-021 Interrupt controller 1
022-023 AR-B1540 : SiS 5582 Chipset Address
AR-B1541 : SiS 5598 Chipset Address
040-04F Timer 1
050-05F Timer 2
060-06F 8042 keyboard/controller
070-071 Real-time clock (RTC), non-maskable interrupt (NMI)
076-077 Watchdog
080-09F DMA page registers
0A0-0A1 Interrupt controller 2
0C0-0DF DMA controller 2
0F0 Clear Math Co-processor
0F1 Reset Math Co-processor
0F8-0FF Math Co-processor
170-178 Fixed disk 1
1F0-1F8 Fixed disk 0
201 Game port
208-20A EMS register 0
214-215 Watchdog
218-21A EMS register 1
278-27F Parallel printer port 3 (LPT 3)
2E8-2EF Serial port 4 (COM 4)
2F8-2FF Serial port 2 (COM 2)
300-31F Prototype card/Streaming Type Adapter
378-37F Parallel printer port 2 (LPT 2)
380-38F SDLC, bisynchronous
3A0-3AF Bisynchronous
3B0-3BF Monochrome display and printer port 1 (LPT 1)
3C0-3CF EGA/VGA adapter
3D0-3DF Color/Graphics monitor adapter
3E8-3EF Serial port 3 (COM 3)
3F0-3F7 Diskette controller
3F8-3FF Serial port 1 (COM 1)
Table 2-2 I/O Port Address Map
2.3.2 PCI Bus Assignment (Bus1)
Pin Signal Name Pin Signal Name
A1 -TRST B1 -12V
A2 +12V B2 TCK
A3 TMS B3 GND
A4 TDI B4 TD0
A5 +5V B5 +5V
A6 -INTA B6 +5V
A7 -OMTC B7 -INTB
A8 +5V B8 -INTD
A9 NC B9 -PRST 1
A10 +5V B10 NC
A11 NC B11 -PRST 2
A12 GND B12 GND
A13 GND B13 GND
A14 NC B14 NC
A15 -RST B15 GND

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Pin Signal Name Pin Signal Name
A16 +5V B16 CLK
A17 -GNT B17 GND
A18 GND B18 -REQ
A19 NC B19 +5V
A20 AD30 B20 AD31
A21 +3.3V B21 AD29
A22 AD28 B22 GND
A23 AD26 B23 AD27
A24 GND B24 AD25
A25 AD24 B25 +3.3V
A26 IDSEL B26 C/BE3
A27 +3.3V B27 AD23
A28 AD22 B28 GND
A29 AD20 B29 AD21
A30 GND B30 AD19
A31 AD18 B31 +3.3V
A32 AD16 B32 AD17
A33 +3.3V B33 C/BE2
A34 -FRAME B34 GND
A35 GND B35 -IRDY
A36 -TRDY B36 +3.3V
A37 GND B37 -DEVSEL
A38 -STOP B38 GND
A39 +3.3V B39 -LOCK
A40 SDONE B40 -PERR
A41 -SB0 B41 +3.3V
A42 GND B42 -SERR
A43 PAR B43 +3.3V
A44 AD15 B44 C/BE1
A45 +3.3V B45 AD14
A46 AD13 B46 GND
A47 AD11 B47 AD12
A48 GND B48 AD10
A49 AD9 B49 GND
Table 2-3 PCI Bus Assignment
Pin Signal Name Pin Signal Name
C1 C/BE0 D1 AD8
C2 +3.3V D2 AD7
C3 AD6 D3 +3.3V
C4 AD4 D4 AD5
C5 GND D5 AD3
C6 AD2 D6 GND
C7 AD0 D7 AD1
C8 +5V D8 +5V
C9 -REQ64 D9 -ACK64
C10 +5V D10 +5V
C11 +5V D11 +5V
Table 2-4 PCI Bus Assignment

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2.3.3 Real-Time Clock and Non-Volatile RAM
The AR-B1540 and AR-B1541 contains a real-time clock compartment that maintains the date and time in addition to
storing configuration information about the computer system. It contains 14 bytes of clock and control registers and
114 bytes of general purpose RAM. Because of using CMOS technology, it consumes very little power and can be
maintained for long period of time using an internal Lithium battery. The contents of each byte in the CMOS RAM
are listed as follows:
Address Description
00 Seconds
01 Second alarm
02 Minutes
03 Minute alarm
04 Hours
05 Hour alarm
06 Day of week
07 Date of month
08 Month
09 Year
0A Status register A
0B Status register B
0C Status register C
0D Status register D
0E Diagnostic status byte
0F Shutdown status byte
10 Diskette drive type byte, drive A and B
11 Fixed disk type byte, drive C
12 Fixed disk type byte, drive D
13 Reserved
14 Equipment byte
15 Low base memory byte
16 High base memory byte
17 Low expansion memory byte
18 High expansion memory byte
19-2D Reserved
2E-2F 2-byte CMOS checksum
30 Low actual expansion memory byte
31 High actual expansion memory byte
32 Date century byte
33 Information flags (set during power on)
34-7F Reserved for system BIOS
Table 2-5 Real-Time Clock & Non-Volatile RAM
2.3.4 Timer
The AR-B1540 and AR-B1541 provides three programmable timers, each with a timing frequency of 1.19 MHz.
Timer 0 The output of this timer is tied to interrupt request 0. (IRQ 0)
Timer 1 This timer is used to trigger memory refresh cycles.
Timer 2 This timer provides the speaker tone.
Application programs can load different counts into this timer to generate various sound frequencies.

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2.4 SERIAL PORT
The ACEs (Asynchronous Communication Elements ACE1 to ACE4) are used to convert parallel data to a serial
format on the transmit side and convert serial data to parallel on the receiver side. The serial format, in order of
transmission and reception, is a start bit, followed by five to eight data bits, a parity bit (if programmed) and one,
one and half (five-bit format only) or two stop bits. The ACEs are capable of handling divisors of 1 to 65535, and
produce a 16x clock for driving the internal transmitter logic.
Provisions are also included to use this 16x clock to drive the receiver logic. Also included in the ACE a completed
MODEM control capability, and a processor interrupt system that may be software tailored to the computing time
required handle the communications link.
The following table is summary of each ACE accessible register
DLAB Port Address Register
Receiver buffer (read)0 base + 0 Transmitter holding register (write)
0 base + 1 Interrupt enable
X base + 2 Interrupt identification (read only)
X base + 3 Line control
X base + 4 MODEM control
X base + 5 Line status
X base + 6 MODEM status
X base + 7 Scratched register
1 base + 0 Divisor latch (least significant byte)
1 base + 1 Divisor latch (most significant byte)
Table 2-6 ACE Accessible Registers
(1) Receiver Buffer Register (RBR)
Bit 0-7: Received data byte (Read Only)
(2) Transmitter Holding Register (THR)
Bit 0-7: Transmitter holding data byte (Write Only)
(3) Interrupt Enable Register (IER)
Bit 0: Enable Received Data Available Interrupt (ERBFI)
Bit 1: Enable Transmitter Holding Empty Interrupt (ETBEI)
Bit 2: Enable Receiver Line Status Interrupt (ELSI)
Bit 3: Enable MODEM Status Interrupt (EDSSI)
Bit 4: Must be 0
Bit 5: Must be 0
Bit 6: Must be 0
Bit 7: Must be 0
(4) Interrupt Identification Register (IIR)
Bit 0: “0” if Interrupt Pending
Bit 1: Interrupt ID Bit 0
Bit 2: Interrupt ID Bit 1
Bit 3: Must be 0
Bit 4: Must be 0
Bit 5: Must be 0
Bit 6: Must be 0
Bit 7: Must be 0

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(5) Line Control Register (LCR)
Bit 0: Word Length Select Bit 0 (WLS0)
Bit 1: Word Length Select Bit 1 (WLS1)
WLS1 WLS0 Word Length
0 0 5 Bits
0 1 6 Bits
1 0 7 Bits
1 1 8 Bits
Bit 2: Number of Stop Bit (STB)
Bit 3: Parity Enable (PEN)
Bit 4: Even Parity Select (EPS)
Bit 5: Stick Parity
Bit 6: Set Break
Bit 7: Divisor Latch Access Bit (DLAB)
(6) MODEM Control Register (MCR)
Bit 0: Data Terminal Ready (DTR)
Bit 1: Request to Send (RTS)
Bit 2: Out 1 (OUT 1)
Bit 3: Out 2 (OUT 2)
Bit 4: Loop
Bit 5: Must be 0
Bit 6: Must be 0
Bit 7: Must be 0
(7) Line Status Register (LSR)
Bit 0: Data Ready (DR)
Bit 1: Overrun Error (OR)
Bit 2: Parity Error (PE)
Bit 3: Framing Error (FE)
Bit 4: Break Interrupt (BI)
Bit 5: Transmitter Holding Register Empty (THRE)
Bit 6: Transmitter Shift Register Empty (TSRE)
Bit 7: Must be 0
(8) MODEM Status Register (MSR)
Bit 0: Delta Clear to Send (DCTS)
Bit 1: Delta Data Set Ready (DDSR)
Bit 2: Training Edge Ring Indicator (TERI)
Bit 3: Delta Receive Line Signal Detect (DSLSD)
Bit 4: Clear to Send (CTS)
Bit 5: Data Set Ready (DSR)
Bit 6: Ring Indicator (RI)
Bit 7: Received Line Signal Detect (RSLD)

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(9) Divisor Latch (LS, MS)
LS MS
Bit 0: Bit 0 Bit 8
Bit 1: Bit 1 Bit 9
Bit 2: Bit 2 Bit 10
Bit 3: Bit 3 Bit 11
Bit 4: Bit 4 Bit 12
Bit 5: Bit 5 Bit 13
Bit 6: Bit 6 Bit 14
Bit 7: Bit 7 Bit 15
Desired Baud Rate Divisor Used to Generate 16x Clock
300 384
600 192
1200 96
1800 64
2400 48
3600 32
4800 24
9600 12
14400 8
19200 6
28800 4
38400 3
57600 2
115200 1
Table 2-7 Serial Port Divisor Latch
2.5 PARALLEL PORT
(1) Register Address
Port Address Read/Write Register
base + 0 Write Output data
base + 0 Read Input data
base + 1 Read Printer status buffer
base + 2 Write Printer control latch
Table 2-8 Registers’Address
(2) Printer Interface Logic
The parallel portion of the SMC37C669 makes the attachment of various devices that accept eight bits of parallel
data at standard TTL level.
(3) Data Swapper
The system microprocessor can read the contents of the printer’s Data Latch through the Data Swapper by reading
the Data Swapper address.

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(4) Printer Status Buffer
The system microprocessor can read the printer status by reading the address of the Printer Status Buffer. The bit
definitions are described as follows:
XXX
12345670
-ERROR
SLCT
PE
-ACK
-BUSY
Figure 2-2 Printer Status Buffer
NOTE: X presents not used.
Bit 7: This signal may become active during data entry, when the printer is off-line during printing, or when the
print head is changing position or in an error state. When Bit 7 is active, the printer is busy and can not
accept data.
Bit 6: This bit represents the current state of the printer’s ACK signal. A 0 means the printer has received the
character and is ready to accept another. Normally, this signal will be active for approximately 5
microseconds before receiving a BUSY message stops.
Bit 5: A 1 means the printer has detected the end of the paper.
Bit 4: A 1 means the printer is selected.
Bit 3: A 0 means the printer has encountered an error condition.

AR-B1540/AR-B1541 User’s Guide
2-10
(5) Printer Control Latch & Printer Control Swapper
The system microprocessor can read the contents of the printer control latch by reading the address of printer
control swapper. Bit definitions are as follows:
XX
12345670
STROBE
AUTO FD XT
INIT
SLDC IN
IRQ ENABLE
DIR(write only)
Figure 2-3 Bit’s Definition
NOTE: X presents not used.
Bit 5: Direction control bit. When logic 1, the output buffers in the parallel port are disabled allowing data driven
from external sources to be read; when logic 0, they work as a printer port. This bit is write only.
Bit 4: A 1 in this position allows an interrupt to occur when ACK changes from low state to high state.
Bit 3: A 1 in this bit position selects the printer.
Bit 2: A 0 starts the printer (50 microseconds pulse, minimum).
Bit 1: A 1 causes the printer to line-feed after a line is printed.
Bit 0: A 0.5 microsecond minimum highly active pulse clocks data into the printer. Valid data must be present
for a minimum of 0.5 microseconds before and after the strobe pulse.

AR-B1540/AR-B1541 User’s Guide
3-1
3. SETTING UP THE SYSTEM
This chapter describes pin assignments for the system’s external connectors and jumpers setting.
! Overview
! System Setting
3.1 OVERVIEW
The AR-B1540 and AR-B1541 are Pentium single CPU board. This section provides hardware’s jumpers settings,
connectors’ locations, and the pin assignments.
1
1
1
1
1
1
8
1
2
1
1
2
J16
J17
J15
M43M42
LED1
LED2
JP9
CN6
M27M26
50
100
81 51
31
1
U6
JP6
M20
M19
M18
M17
U14
U11
U12
1
SIMM2
1
SIMM1
CN8
J13
BUS1
U7
J14
SW2
CN5
J12
DB2
DB1 U9
CN7
J2
U10
J1
CN2
CN9
JP5
JP8
JP7
J3
50
100
81 51
31
1
U5
CN4
JP1 JP3
J5
J4
J10 J8
U15
CN1
CN3
M7
M6 M5
M4
M3
M2
M1
Figure 3-1 External System Location

AR-B1540/AR-B1541 User’s Guide
3-2
3.2 SYSTEM SETTING
Jumper pins allow you to set specific system parameters. Set them by changing the pin location of jumper blocks.
(A jumper block is a small plastic-encased conductor that slips over the pins.) To change a jumper setting, remove
the jumper from its current location with your fingers or small needle-nosed pliers. Place the jumper over the two
pins designated for the desired setting. Press the jumper evenly onto the pins. Be careful not to bend the pins.
We will show the locations of the AR-B1540/AR-B1541 jumper pins, and the factory-default setting.
CAUTION: Do not touch any electronic component unless you are safely grounded. Wear a grounded wrist strap
or touch an exposed metal part of the system unit chassis. The static discharges from your fingers can
permanently damage electronic components.
3.2.1 Hard Disk (IDE) Connector (CN2)
A 40-pin header type connector (CN2) is provided to interface with up to two embedded hard disk drives (IDE AT
bus). This interface, through a 40-pin cable, allows the user to connect up to two drives in a “daisy chain” fashion.
To enable or disable the hard disk controller, please use the BIOS Setup program. The following table illustrates
the pin assignments of the hard disk drive’s 40-pin connector.
1
2
Figure 3-2 CN2: Hard Disk (IDE) Connector
Pin Signal Pin Signal
1 -RESET 2 GROUND
3 DATA 7 4 DATA 8
5 DATA 6 6 DATA 9
7 DATA 5 8 DATA 10
9 DATA 4 10 DATA 11
11 DATA 3 12 DATA 12
13 DATA 2 14 DATA 13
15 DATA 1 16 DATA 14
17 DATA 0 18 DATA 15
19 GROUND 20 NOT USED
21 DRQ A 22 GROUND
23 -IOW A 24 GROUND
25 -IOR A 26 GROUND
27 -CHRDY A 28 NOT USED
29 DACK A 30 GROUND
31 -IRQ A 32 NOT USED
33 SA 1 34 NOT USED
35 SA 0 36 SA 2
37 CS 0 38 CS 1
39 HD LED A 40 GROUND
Table 3-1 HDD Pin Assignment

AR-B1540/AR-B1541 User’s Guide
3-3
3.2.2 PC/104 Connector
(1) 64-Pin PC/104 Connector Bus A & B (CN7)
1
2
64-Pin PC/104 Connector 63
64
Figure 3-3 CN7: 64-Pin PC/104 Connector Bus A & B
-IOCHCK ---
SD7 ---
SD6 ---
SD5 ---
SD4 ---
SD3 ---
SD2 ---
SD1 ---
SD0 ---
IOCHRDY---
AEN ---
SA19 ---
SA18 ---
SA17 ---
SA16 ---
SA15 ---
SA14 ---
SA13 ---
SA12 ---
SA11 ---
SA10 ---
A1
A2
A3
A4
A5
A6
A7
A8
A9
A10
A11
A12
A13
A14
A15
A16
A17
A18
A19
A20
A21
A22
A23
A24
A25
A26
A27
A28
A29
A30
A31
A32
--- GND
--- RSTDRV
--- +5 VDC
--- IRQ9
--- -5 VDC
--- DRQ2
--- -12 VDC
--- -ZWS
--- +12 VDC
--- GND
--- -SMEMW
--- -SMEMR
--- -IOW
--- -IOR
--- -DACK3
--- DRQ3
--- -DACK1
--- DRQ1
--- -REFRESH
--- BUSCLK
--- IRQ7
SA9 ---
SA8 ---
SA7 ---
SA6 ---
SA5 ---
SA4 ---
SA3 ---
SA2 ---
SA1 ---
SA0 ---
GND ---
B1
B2
B3
B4
B5
B6
B7
B8
B9
B10
B11
B12
B13
B14
B15
B16
B17
B18
B19
B20
B21
B22
B23
B24
B25
B26
B27
B28
B29
B30
B31
B32
--- IRQ6
--- IRQ5
--- IRQ4
--- IRQ3
--- -DACK2
--- TC
--- BALE
--- +5 VDC
--- OSC
--- GND
--- GND
CN7
12
Figure 3-4 CN7: 64-Pin PC/104 Connector Bus A & B
(2) 40-Pin PC/104 Connector Bus C & D (CN9)
1
239 40
40 Pin PC/104 Connector
Figure 3-5 CN9: 40-Pin PC/104 Connector Bus C & D
GND ---
-BHE ---
LA23 ---
LA22 ---
LA21 ---
LA20 ---
LA19 ---
LA18 ---
LA17 ---
-MEMR ---
-MEMW ---
SD8 ---
SD9 ---
SD10 ---
SD11 ---
SD12 ---
SD13 ---
SD14 ---
SD15 ---
Not Used ---
C1
C2
C3
C4
C5
C6
C7
C8
C9
C10
C11
C12
C13
C14
C15
C16
C17
C18
C19
C20
--- GND
--- -MEM16
--- -IOCS16
--- IRQ10
--- IRQ11
--- IRQ12
--- IDEIRQA
--- IDEIRQB
--- -DACK0
--- DRQ0
--- -DACK5
--- DRQ5
--- -DACK6
--- DRQ6
--- -DACK7
--- DRQ7
--- +5 VDC
--- -MASTER
--- GND
--- GND
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
D12
D13
D14
D15
D16
D17
D18
D19
D20
12
CN9
Figure 3-6 CN9: 40-Pin PC/104 Connector Bus C & D