Diamond Systems ETX-N270 User manual

init
ETX-N270
ETX 3.0 Computer-On-Module Based on Intel®Atom N270
Copyright 2009
FOR TECHNICAL SUPPORT Diamond Systems Corporation
PLEASE CONTACT: 1255 Terra Bella Ave.
Mountain View, CA 94043 USA
[e-mail] Tel [phone]
Fax [phone]
www.diamondsystems.com
Revision
Date
Comment
1.1
7/15/09
Initial release
1.3
8/17/09
Minor update

ETX-270 User Manual 1.3www.diamondsystems.com Page 2
CONTENTS
IMPORTANT SAFE-HANDLING INFORMATION......................................................................................................3
1. INTRODUCTION.................................................................................................................................................4
1.1 Features.........................................................................................................................................................4
2. FUNCTIONAL OVERVIEW.................................................................................................................................6
2.1 Block Diagram ...............................................................................................................................................6
2.2 Board Dimensions, Mounting Holes, and Connectors...................................................................................7
2.3 Bus and Interface Connector Summary........................................................................................................9
2.4 ETX Bus Connectors.....................................................................................................................................9
2.5 Other Interface Connectors ...........................................................................................................................9
3. GETTING STARTED........................................................................................................................................ 10
3.1 ETX Development Kits ............................................................................................................................... 11
3.2 Configuring the Hardware........................................................................................................................... 11
3.3 Booting the System .................................................................................................................................... 12
3.4 BIOS Setup Utility....................................................................................................................................... 12
3.4.1 Standard CMOS Features ................................................................................................................. 12
3.4.2 Advanced BIOS Features.................................................................................................................. 12
3.4.3 Advanced Chipset Features .............................................................................................................. 13
3.4.4 Integrated Peripherals........................................................................................................................ 13
3.4.5 Power Management Setup ................................................................................................................ 13
3.4.6 PnP/PCI Configuration....................................................................................................................... 14
3.4.7 Other Settings and Utilities ................................................................................................................ 14
3.5Operating System Drivers .......................................................................................................................... 14
3.6 BIOS Beep Code List ................................................................................................................................. 14
4. INTERFACE CONNECTOR DETAILS............................................................................................................. 15
4.1 ETX1 Connector......................................................................................................................................... 16
4.1.1 PCI bus signals.................................................................................................................................. 17
4.1.2 USB signals ....................................................................................................................................... 18
4.1.3 Audio interface................................................................................................................................... 18
4.1.4 Miscellaneous functions..................................................................................................................... 19
4.2 ETX2 Connector......................................................................................................................................... 20
4.3 ETX3 Connector......................................................................................................................................... 21
4.3.1 Analog video output........................................................................................................................... 22
4.3.2 TV video output.................................................................................................................................. 22
4.3.3 LCD interface..................................................................................................................................... 23
4.3.4 Serial port interfaces.......................................................................................................................... 23
4.3.5 Keyboard, mouse, and infrared transceiver interfaces...................................................................... 24
4.3.6 Parallel port interface......................................................................................................................... 24
4.3.7 Floppy drive interface......................................................................................................................... 25
4.3.8 Miscellaneous functions..................................................................................................................... 26
4.4 ETX4 Connector......................................................................................................................................... 27
4.4.1 IDE interfaces .................................................................................................................................... 28
4.4.2 Ethernet port ...................................................................................................................................... 29
4.4.3 Power control and management........................................................................................................ 29
4.4.4 Miscellaneous signals........................................................................................................................ 30
4.5 SATA Connectors....................................................................................................................................... 30
4.6 SDVO Connector........................................................................................................................................ 31
5. APPENDIX: SYSTEM RESOURCES REFERENCE....................................................................................... 32
5.1 BIOS Memory Mapping .............................................................................................................................. 32
5.2 I/O Port Address Map................................................................................................................................. 33
5.3 Interrupt Request (IRQ) Lines .................................................................................................................... 35
5.4 BIOS POST Codes..................................................................................................................................... 36

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IMPORTANT SAFE-HANDLING INFORMATION
WARNING: ESD-Sensitive Electronic Equipment!
Observe ESD-safe handling procedures when working with this product.
Always use this product in a properly grounded work area and wear
appropriate ESD-preventive clothing and/or accessories.
Always store this product in ESD-protective packaging when not in use.
Safe Handling Precautions
The ETX-N270 contains numerous I/O connectors that connect to sensitive electronic components. This creates
many opportunities for accidental damage during handling, installation and connection to other equipment. The
list here describes common causes of failure found on boards returned to Diamond Systems for repair. This
information is provided as a source of advice to help you prevent damaging your Diamond (or any vendor’s)
embedded computer boards.
ESD damage –This type of damage is almost impossible to detect, because there is no visual sign of failure or
damage. The symptom is that the board simply stops working, because some component becomes defective.
Usually the failure can be identified and the chip can be replaced. To prevent ESD damage, always follow proper
ESD-prevention practices when handling computer boards.
Damage during handling or storage –On some boards we have noticed physical damage from mishandling. A
common observation is that a screwdriver slipped while installing the board, causing a gouge in the PCB surface
and cutting signal traces or damaging components.
Another common observation is damaged board corners, indicating the board was dropped. This may or may not
cause damage to the circuitry, depending on what is near the corner. Most of our boards are designed with at
least 25 mils clearance between the board edge and any component pad, and ground / power planes are at least
20 mils from the edge to avoid possible shorting from this type of damage. However these design rules are not
sufficient to prevent damage in all situations.
A third cause of failure is when a metal screwdriver tip slips, or a screw drops onto the board while it is powered
on, causing a short between a power pin and a signal pin on a component. This can cause overvoltage / power
supply problems described below. To avoid this type of failure, only perform assembly operations when the
system is powered off.
Sometimes boards are stored in racks with slots that grip the edge of the board. This is a common practice for
board manufacturers. However our boards are generally very dense, and if the board has components very close
to the board edge, they can be damaged or even knocked off the board when the board tilts back in the rack.
Diamond recommends that all our boards be stored only in individual ESD-safe packaging. If multiple boards are
stored together, they should be contained in bins with dividers between boards. Do not pile boards on top of each
other or cram too many boards into a small location. This can cause damage to connector pins or fragile
components.
Power supply wired backwards –Our power supplies and boards are not designed to withstand a reverse
power supply connection. This will destroy each IC that is connected to the power supply. In this case the board
will most likely will be unrepairable and must be replaced. A chip destroyed by reverse power or by excessive
power will often have a visible hole on the top or show some deformation on the top surface due to vaporization
inside the package. Check twice before applying power!

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1. INTRODUCTION
The ETX-N270 is a highly integrated computer-on-module (COM) based on the low power, high performance Intel
Atom N270 processor clocked at 1.6GHz. The module provides an SO-DIMM socket for up to 2GB of DDR2
DRAM, and provides interface controllers for high-resolution CRT and LVDS-interfaced displays, 10/100Mbps
Ethernet, SATA and IDE storage devices, USB 2.0, audio, serial, parallel, and PS/2 ports. Additionally, the ETX-
N270 provides a high degree of system expansion flexibility via the presence of both 32-bit PCI and 16-bit ISA
expansion buses on its ETX 3.0 compliant baseboard interface connectors.
1.1 Features
Processor:
Intel® Atom N270
533MHz FSB and 512KB L2 Cache
Chipset:
Intel 945GSE and Intel ICH7M
RAM:
200-pin SO-DIMM socket
Supports up to 2GB DDR2 SDRAM (400/533MHz)
Graphics:
Based on Intel GMA950 graphics core
VGA CRT interface; up to 2048x1536 resolution
Dual channel 18-bit LVDS flat panel interface (LVDS); provides LCD backlight control signals
TV output
Intel-compliant SDVO port supports VGA, DVI, LVDS, TV-out; up to 200 megapixels/sec data rate
(connector directly on ETX module)
Supports dual independent displays
Audio:
Realtek ALC655 AC’97 CODEC
Mic in, line in/out signals
IDE interface:
1 UltraATA 100/66/33 interface
Supports two devices (Master/Slave)
Usable in PIO or UDMA mode
SATA interfaces:
2 SATA ports, supporting one device each
Up to 150MB/s data transfer rates
Connectors directly on ETX COM module
Floppy/parallel port:
Shared interface
Parallel port supports SPP/EPP/ECP modes
Ethernet interface:
1 10/100Base-T port
Based on Intel 82562
Serial ports:
2 16550-compatible ports
Logic-level signaling
Keyboard/mouse:
Standard PS/2 keyboard and mouse ports
USB keyboard/mouse also supported

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USB:
4 USB 2.0 ports
Other:
SMbus, I2C, IrDA serial interfaces
PC speaker interface
Watchdog timer; supports 255-level reset
Dual system expansion buses:
16-bit ISA bus
32-bit PCI bus; supports 4 PCI masters
Size:
ETX 3.0 compliant form-factor (physical and electrical)
4.5 x 3.7 inches (95mm x 114mm)
Input voltage:
System power: +5V DC +/-5%
Real-time clock backup: +2.0 to 3.6V DC
Operating environment:
-20o to +70oC operating temperature
0 to 90% operating humidity (non-condensing)
BIOS:
Phoenix-Award PnP flash BIOS
Note: The ETX 3.0 specification is available for download from the ETX Industrial Group’s
website (http://www.etx-ig.de/specs/specs.php).

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2. FUNCTIONAL OVERVIEW
2.1 Block Diagram
Figure 1 shows the ETX-N270 COM’s functional blocks, ETX bus, and peripheral interface signals.
Figure 1: Functional Block Diagram

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2.2 Board Dimensions, Mounting Holes, and Connectors
The two diagrams below show the mechanical dimensions of the ETX-N270’s board outline and five mounting
holes, as well as the position of all connectors on both the top and bottom sides of the board.
Figure 2: Board Layout –Top

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Figure 3: Board Layout –Bottom

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2.3 Bus and Interface Connector Summary
The ETX-N270 has seven interface connectors, as listed in the tables below. With the exception of SDVO1, these
connectors are defined in accordance with the ETX 3.0 Computer-on-Module (COM) Specification. Signal
functions relating to all of the module’s interface connectors are discussed in greater detail in Section 4 of this
document.
2.4 ETX Bus Connectors
Connector
Location
Pins
Function
ETX1
Bottom
100
PCI bus, USB ports, audio interface, serial IRQ
ETX2
Bottom
100
ISA bus
ETX3
Bottom
100
VGA, LCD (LVDS), TV video, serial ports, PS2 keyboard
and mouse, parallel port, floppy interface
ETX4
Bottom
100
IDE ports, Ethernet, power supply control, speaker, RTC
(real-time clock) backup battery input, I2C bus, SM bus
2.5 Other Interface Connectors
Connector
Location
Pins
Function
SATA1
Top
7
Serial ATA channel 1
SATA2
Top
7
Serial ATA channel 2
SDVO1
Bottom
30
Serial Digital Video Out (SDVO) port

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Important Safe-Handling Information
WARNING: ESD-Sensitive Electronic Equipment!
Observe ESD-safe handling procedures when working
with this product.
Always use this product in a properly grounded work area
and wear appropriate ESD-preventive clothing and/or
accessories.
Always store this product in ESD-protective packaging
when not in use.
Please refer to page 4 of this manual (“Important Safe-Handling Information”) for further
details.
3. GETTING STARTED
This section of the ETX-N270 User Manual covers basic hardware setup, power connection, system boot-up, and
initial software configuration. First-time ETX-N270 users normally receive the product as part of one of Diamond’s
Development Kits, which provide everything needed to ensure rapid application development.

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3.1 ETX Development Kits
To facilitate evaluation and development, the ETX-N270 is normally supplied pre-integrated into one of Diamond’s
ETX development kits (pictured below). This approach increases project efficiency and reduces risks by providing
a known good environment for rapid application development.
Diamond’s ETX development kits feature baseboards with I/O connectors for quick and easy access to nearly all
system interfaces, a CompactFlash socket, and modular PC/104-Plus expansion. The kits –which include both
generic models and application-oriented ETX baseboards in various form-factors –extend the ETX-N270’s
functionality by adding serial and LAN ports, RS-232/422/485 signal buffering, CompactFlash sockets, industry-
leading data acquisition I/O functions, and more. Additionally, the kits come with SO-DIMM memory, an extensive
set of interface cables, drivers for Linux and Windows operation, and full documentation.
Two examples appear below.
ETX form-factor development kit: Matches
the footprint of the ETX-N270 and provides
connectors for system I/O, CompactFlash,
PC/104-Plus expansion, two additional serial
ports, RS-232/422/485 buffering, a digital I/O
port, and a second Ethernet LAN interface.
EPIC form-factor development kit: Provides
connectors for system I/O, CompactFlash,
PC/104-Plus expansion, four additional serial
ports, RS-232/422/485 buffering, a second
Ethernet port, a 5V/7-28V DC-to-DC power
supply, and an industry-leading data acquisition
subsystem.
3.2 Configuring the Hardware
Assuming you are using one of Diamond’s baseboards and heat-spreaders or heatsinks with the ETX-N270,
prepare the hardware as follows:
If the SO-DIMM memory module is not already installed, carefully insert it into the socket provided on the top-
side of the ETX-N270 module. Refer to the specifications in the introduction of this manual for memory
capacity and speed requirements.
Secure the heat-spreader (or heatsink) to the top-side of the ETX-N270 module using the single short screw
provided with the heat-spreader (or heatsink), taking care to align the four corner mounting holes of the heat-
spreader (or heatsink) with the four corresponding standoffs on the top of the ETX-N270. Note: This mounting
screw attaches to the heat-spreader (or heatsink) via a hole near the middle of ETX-N270 module, and
screws in from the bottom-side of the ETX module.
Using the four long screws provided with the heat-spreader (or heatsink), secure the heat-spreader (or
heatsink) to the corresponding standoffs located in the four corners of the top of the ETX-N270 module. If the
ETX module is to being installed in an enclosure, align the heat-spreader’s (or heatsink’s) corner mounting

ETX-270 User Manual 1.3www.diamondsystems.com Page 12
holes with corresponding hole-pattern on the enclosure before inserting and tightening
the four mounting screws. Depending on the thickness of the enclosure or chassis material, slightly longer
screws may be required.
Connect the baseboard to a keyboard, monitor, mouse, mass storage device, other desired peripherals, and a
source of DC power. Refer to the baseboard’s User Manual for interface cabling considerations.
Connect the baseboard to a suitable source of DC power, as described in its User Manual.
3.3 Booting the System
Power-up the VGA video monitor. Then power-up the system power supply. The ETX-N270 module should begin
its boot-up sequence immediately, as evidenced by BIOS messages on the connected VGA display. You can run
the BIOS Setup utility and proceed to install an operating system on the boot drive just as you would on a normal
desktop PC.
3.4 BIOS Setup Utility
The Award BIOS provides a Setup utility for specifying system configuration and settings. Pressing the <Del> key
shortly after power is applied to the ETX-N270 launches the BIOS Setup utility. Watch for the following message:
Press <DEL> to Enter Setup
The BIOS Setup utility’s main menu provides access to the following configuration and settings pages, along with
several exit options. Setup categories include the following:
Standard CMOS features
Advanced BIOS features
Advanced chipset features
Integrated peripherals
PnP/PCI configuration
These are discussed briefly below.
3.4.1 Standard CMOS Features
The Standard CMOS Features function includes settings for RTC date/time initialization, IDE and floppy drive
detection and configuration, default video mode, and boot error handling options. This function should be re-run if
the system’s configuration is changed, the onboard battery fails, or the configuration stored in CMOS memory is
lost or corrupt.
3.4.2 Advanced BIOS Features
The Advanced BIOS Features function provides configuration options for boot device priority, CPU L3 Cache,
quick POST (power-on self test), and several other system parameters.
One key configuration setting is the designation of “First” and “Second” boot devices. This directs the BIOS to
scan for a bootable operating system in two locations, which can be floppy, CD-ROM, hard drive, USB devices, or
LAN devices. Additionally, you can specify an alternative location for the BIOS to scan, in case these are not
found or do not contain a bootable OS.
Other settings available from this Setup page include boot-up NumLock status, a security password option, and
selection of the system’s APIC (Advanced Programmable Interrupt Controller) mode.

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3.4.3 Advanced Chipset Features
From this setup page you can configure the size of the video controller’s on-chip frame buffer, set up the
controller’s DVMT (Dynamic Video Memory Technology) mode and memory size, and specify what type of display
will be used as the system’s boot-up console output device.
DVMT is an advanced video controller function that dynamically allocates system memory to be used as video
memory in order to efficiently use of available resources to maximize graphics performance. The DVMT-related
BIOS settings configure the behavior of the DVMT function, including how much system memory is made
available for video memory purposes.
The default display setting allows selection among CRT, LCD, CRT plus LCD (default), SDVO LVDS, TV out, or
CRT plus SDVO LVDS devices. Other settings specify the resolution of devices connected to the LCD, SDVO, or
TV output ports. The resolutions supported in each mode are listed below.
Display Interface Port
Resolutions Supported
CRT port
Up to 2048 x 1536 resolution
LCD port
640x480, 800x600, 1024x768, 1280x1024,
1400x1050, 1600x1200, 1280x768, 1680x1050,
1920x1200, 1204x678 (24-bit)
SDVO port
800x600, 1024x768,
TV output
NTSC, PAL
3.4.4 Integrated Peripherals
This Setup section offers the ability to configure various onboard functions and peripheral controllers, including
enable/disable, mode, and other options for the board’s USB, audio, IDE, Serial ATA, floppy controller, serial, IR,
and parallel ports.
A few of the available options include:
Mode controls for faster IDE data transfer, including 33MB/sec Ultra DMA33 feature
Onboard serial port mode, handshake, address, and interrupt channel selection
Parallel port mode selection among SPP, EPP, ECP, ECP+EPP, or “normal”, plus several settings
relating to the EPP and ECP modes
3.4.5 Power Management Setup
Here, you can specify a host of options that regulate how the board’s power management features behave.
Included are options for enabling/disabling the board’s ACPI (Advanced Configuration and Power Interface)
capabilities, and specifying the degree and behavior of power management relative to the system’s mass storage
devices and display.
Additionally, this section of Setup provides several options for automatically powering up the system or resuming
from a suspended state. These include:
Power-up automatically following unexpected power loss
Resume operation based on modem or LAN connection
Resume operation based on RTC alarm
Resume operation following one of several time intervals

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3.4.6 PnP/PCI Configuration
This section of Setup provides options for configuration of devices connected to the ETX-N270’s PCI bus,
including the choice between automatic “plug-and-play” (PnP) configuration of IRQ and DMA channel settings. If
PnP is disabled, you can specific desired IRQ and DMA channels for PCI devices here.
3.4.7 Other Settings and Utilities
A few additional status and control functions are available from Setup’s main menu. These include:
CPU temperature status
CPU cooling fan status
CPU voltage status
Reload default BIOS settings
Set system boot password
Exit Setup with or without saving changes
3.5 Operating System Drivers
Drivers for Windows XP and Linux 2.6, if required, are included on the Software and Documentation CD that is
provided along with the ETX-N270 or in its Development Kit. To locate the ETX-N270 module’s software drivers
on the CD, view the index.html file in the CD’s root directory, locate “Computer-on-Modules,” and then click on
“ETX-COMs.” This software is also available for download from Diamond’s website.
3.6 BIOS Beep Code List
Beep Sound
Message
1 short
System is booting normally
2 short
CMOS setting error
1 long + 1 short
DRAM error
1 long + 2 short
Display card or monitor connected error
1 long + 3 short
Keyboard error
1 long + 9 short
ROM error
long (continuous)
DRAM not inserted correctly
short (continuous)
Power supply problem

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4. INTERFACE CONNECTOR DETAILS
This section describes the functions available on all of the ETX-N270’s bus and I/O interface connectors. The
ETX 3.0 specification, which provides more detail regarding the signals present on the ETX1, ETX2, ETX3, and
ETX4 connectors, is available from the ETX Industrial Group’s website (http://www.etx-ig.de/specs/specs.php).
Also available from that site is the latest ETX Design Guide, which provides further details on the ETX connector
signal functions and interface considerations. Several other relevant specifications are referenced below.

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4.1 ETX1 Connector
The 100-pin, high-density ETX1 connector implements the board’s PCI bus, USB, and audio signals, as indicated
in the table below. Further information regarding each of these signal groups follows the table. (Note: Pins
designated “RESERVED” should be left unconnected.)
GND
1
2
GND
VCC
51
52
VCC
PCICLK3
3
4
PCICLK4
PAR
53
54
SERR#
GND
5
6
GND
GPERR#
55
56
RESERVED
PCICLK1
7
8
PCICLK2
PME#
57
58
USB2-
REQ3#
9
10
GNT3#
LOCK#
59
60
DEVSEL#
GNT2#
11
12
3V
TRDY#
61
62
USB3-
REQ2#
13
14
GNT1#
IRDY#
63
64
STOP#
REQ1#
15
16
3V
FRAME#
65
66
USB2+
GNT0#
17
18
RESERVED
GND
67
68
GND
VCC
19
20
VCC
AD16
69
70
CBE2#
SERIRQ
21
22
REQ0#
AD17
71
72
USB3+
AD0
23
24
3V
AD19
73
74
AD18
AD1
25
26
AD2
AD20
75
76
USB0-
AD4
27
28
AD3
AD22
77
78
AD21
AD6
29
30
AD5
AD23
79
80
USB1-
CBE0#
31
32
AD7
AD24
81
82
CBE3#
AD8
33
34
AD9
VCC
83
84
VCC
GND
35
36
GND
AD25
85
86
AD26
AD10
37
38
AUXAL
AD28
87
88
USB0+
AD11
39
40
MIC
AD27
89
90
AD29
AD12
41
42
AUXAR
AD30
91
92
USB1+
AD13
43
44
ASVCC
PCIRST#
93
94
AD31
AD14
45
46
SNDL
INTC#
95
96
INTD#
AD15
47
48
ASGND
INTA#
97
98
INTB#
CBE1#
49
50
SNDR
GND
99
100
GND

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4.1.1 PCI bus signals
This set of pins implements the module’s PCI expansion bus. For further information regarding the functions of
the PCI bus signals, refer to the PCI Bus Specification, available from the PCI Special Interest Group
(http://www.pcisig.com/specifications).
Signal Name
Signal function
Direction
PCICLK1-4
PCI clock outputs for external PCI devices
Out
REQ0-3#
Bus Request signals of PCI Masters
In
GNT0-3#
Grant signals to PCI Masters
Out
AD0-31
PCI address and data bus signals
In/Out
CBE0-3#
PCI Bus command and byte enables
In/Out
PAR
PCI bus parity bit
In
SERR#
System Error or PCI Clock RUN
In/Out
GPERR#
Parity Error
In/Out
PME#
Power management event
In/Out
LOCK#
Lock resource signal
In/Out
DEVSEL#
Device select
In/Out
TRDY#
Target ready
In/Out
IRDY#
Initiator ready
In/Out
STOP#
Stop
In/Out
FRAME#
Cycle frame
In/Out
PCIRST#
PCI bus reset
Out
INTA#
PCI interrupt A
In
INTB#
PCI interrupt B
In
INTC#
PCI interrupt C
In
INTD#
PCI interrupt D
In

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4.1.2 USB signals
These pins provide connections to the board’s four USB channels. For further information regarding the functions
of the USB signals listed above, refer to the USB 2.0 Specification, available from the USB Implementers Forum
(http://www.usb.org).
Signal Name
Signal Function
Direction
USB0+
USB Port 0 data +
In/Out
USB0-
USB Port 0 data -
In/Out
USB1+
USB Port 1 data +
In/Out
USB1-
USB Port 1 data -
In/Out
USB2+
USB Port 2 data +
In/Out
USB2-
USB Port 2 data -
In/Out
USB3+
USB Port 3 data +
In/Out
USB3-
USB Port 3 data -
In/Out
4.1.3 Audio interface
These pins carry stereo audio input and output as indicated.
Signal Name
Signal Function
Direction
SNDL
Line-level stereo output left; drives a 5k ohm load
Out
SNDR
Line-level stereo output right; drives a 5k ohm load
Out
AUXAL
Auxiliary A input left
In
AUXAR
Auxiliary A input right
In
MIC
Microphone input
In
ASGND
Analog ground
n/a
ASVCC
Power supply for audio controller
n/a

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4.1.4 Miscellaneous functions
These pins carry power and ground signals and an interrupt request as indicated.
Signal Name
Signal Function
Direction
VCC
+5V ±5% DC power input
In
GND
Power ground
n/a
3V
+3.3V ± 5% supply generated on the ETX module, for
powering external devices (500mA max. external load)
Out
RESERVED
Do not connect
n/a
SERIRQ
Serial interrupt request
In
Caution: Do not connect the 3V pins (pins 12 and 16) of EXT1 to an external power source!

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4.2 ETX2 Connector
The 100-pin, high-density ETX2 connector implements the board’s ISA bus signals, as indicated in the table
below. For further information on the module’s ISA bus signals, refer to the ETX 3.0 Specification.
GND
1
2
GND
VCC
51
52
VCC
SD14
3
4
SD15
SA6
53
54
IRQ5
SD13
5
6
MASTER#
SA7
55
56
IRQ6
SD12
7
8
DREQ7
SA8
57
58
IRQ7
SD11
9
10
DACK7#
SA9
59
60
SYSCLK
SD10
11
12
DREQ6
SA10
61
62
REFSH#
SD9
13
14
DACK6#
SA11
63
64
DREQ1
SD8
15
16
DREQ5
SA12
65
66
DACK1#
MEMW#
17
18
DACK5#
GND
67
68
GND
MEMR#
19
20
DREQ0
SA13
69
70
DREQ3
LA17
21
22
DACK0#
SA14
71
72
DACK3#
LA18
23
24
IRQ14
SA15
73
74
IOR#
LA19
25
26
IRQ13
SA16
75
76
IOW#
LA20
27
28
IRQ12
SA18
77
78
SA17
LA21
29
30
IRQ11
SA19
79
80
SMEMR#
LA22
31
32
IRQ10
IOCHRDY
81
82
AEN
LA23
33
34
IO16#
VCC
83
84
VCC
GND
35
36
GND
SD0
85
86
SMEMW
SBHE#
37
38
M16#
SD2
87
88
SD1
SA0
39
40
OSC
SD3
89
90
NOWS#
SA1
41
42
BALE
DREQ2
91
92
SD4
SA2
43
44
TC
SD5
93
94
IRQ9
SA3
45
46
DACK2#
SD6
95
96
SD7
SA4
47
48
IRQ3
IOCHK#
97
98
RSTDRV
SA5
49
50
IRQ4
GND
99
100
GND