Keithley PIO-24 User manual

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PIO-24 Parallel Digital Interface Board
User’s Guide
A GREATER MEASURE OF CONFIDENCE
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The information contained in this manual is believed to be accurate and reliable. However, the man-
ufacturer assumes no responsibility for its use; nor for any infringements of patents or other rights
of third parties that may result from its use. No license is granted by implication or otherwise under
any patent rights of the manufacturer.
Note:
DriverLINX, SSTNET, and LabOBJX are registered trademarks and DriverLINX/VB is a trade-
mark of Scientific Software Tools, Inc.
Microsoft and Windows are registered trademarks and Visual C++ and Visual Basic are trade-
marks of Microsoft Corporation.
Borland is a registered trademark and Borland C++, Delphi, and Turbo Pascal are trademarks of
Borland International, Inc.
IBM is a registered trademark of International Business Machines Corporation.
Acrobat is a registered trademark of Adobe Systems Incorporated.
All other brand and product names are trademarks or registered trademarks of their respective
companies.
Copyright © Keithley Instruments, Inc., 1999, 1991.
All rights reserved. Reproduction or adaptation of any part of this documentation
beyond that permitted by Section 117 of the 1979 United States Copyright Act
without permission of the Copyright owner is unlawful.
THE MANUFACTURER SHALL NOT BE LIABLE FOR ANY SPECIAL, INCIDENTAL, OR
CONSEQUENTIAL DAMAGES RELATED TO THE USE OF THIS PRODUCT. THIS PROD-
UCT IS NOT DESIGNED WITH COMPONENTS OF A LEVEL OF RELIABILITY THAT IS
SUITED FOR USE IN LIFE SUPPORT OR CRITICAL APPLICATIONS.
back of front cover pg Page 1 Wednesday, April 11, 2001 10:17 AM
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WARRANTY
Hardware
Keithley Instruments, Inc. warrants that, for a period of one (1) year from the date of shipment (3 years for Models 2000,
2001, 2002, 2010 and 2700), the Keithley Hardware product will be free from defects in materials or workmanship. This
warranty will be honored provided the defect has not been caused by use of the Keithley Hardware not in accordance with
the instructions for the product. This warranty shall be null and void upon: (1) any modification of Keithley Hardware that
is made by other than Keithley and not approved in writing by Keithley or (2) operation of the Keithley Hardware outside
of the environmental specifications therefore.
Upon receiving notification of a defect in the Keithley Hardware during the warranty period, Keithley will, at its option,
either repair or replace such Keithley Hardware. During the first ninety days of the warranty period, Keithley will, at its
option, supply the necessary on site labor to return the product to the condition prior to the notification of a defect. Failure
to notify Keithley of a defect during the warranty shall relieve Keithley of its obligations and liabilities under this
warranty.
Other Hardware
The portion of the product that is not manufactured by Keithley (Other Hardware) shall not be covered by this warranty,
and Keithley shall have no duty of obligation to enforce any manufacturers' warranties on behalf of the customer. On those
other manufacturers’ products that Keithley purchases for resale, Keithley shall have no duty of obligation to enforce any
manufacturers’ warranties on behalf of the customer.
Software
Keithley warrants that for a period of one (1) year from date of shipment, the Keithley produced portion of the software or
firmware (Keithley Software) will conform in all material respects with the published specifications provided such Keithley
Software is used on the product for which it is intended and otherwise in accordance with the instructions therefore.
Keithley does not warrant that operation of the Keithley Software will be uninterrupted or error-free and/or that the Keithley
Software will be adequate for the customer's intended application and/or use. This warranty shall be null and void upon any
modification of the Keithley Software that is made by other than Keithley and not approved in writing by Keithley.
If Keithley receives notification of a Keithley Software nonconformity that is covered by this warranty during the warranty
period, Keithley will review the conditions described in such notice. Such notice must state the published specification(s)
to which the Keithley Software fails to conform and the manner in which the Keithley Software fails to conform to such
published specification(s) with sufficient specificity to permit Keithley to correct such nonconformity. If Keithley deter-
mines that the Keithley Software does not conform with the published specifications, Keithley will, at its option, provide
either the programming services necessary to correct such nonconformity or develop a program change to bypass such
nonconformity in the Keithley Software. Failure to notify Keithley of a nonconformity during the warranty shall relieve
Keithley of its obligations and liabilities under this warranty.
Other Software
OEM software that is not produced by Keithley (Other Software) shall not be covered by this warranty, and Keithley shall
have no duty or obligation to enforce any OEM's warranties on behalf of the customer.
Other Items
Keithley warrants the following items for 90 days from the date of shipment: probes, cables, rechargeable batteries, diskettes,
and documentation.
Items not Covered under Warranty
This warranty does not apply to fuses, non-rechargeable batteries, damage from battery leakage, or problems arising from
normal wear or failure to follow instructions.
Limitation of Warranty
This warranty does not apply to defects resulting from product modification made by Purchaser without Keithley's express
written consent, or by misuse of any product or part.
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Disclaimer of Warranties
EXCEPT FOR THE EXPRESS WARRANTIES ABOVE KEITHLEY DISCLAIMS ALL OTHER WARRANTIES,
EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION, ALL IMPLIED WARRANTIES OF MERCHANT-
ABILITY AND FITNESS FOR A PARTICULAR PURPOSE. KEITHLEY DISCLAIMS ALL WARRANTIES WITH
RESPECT TO THE OTHER HARDWARE AND OTHER SOFTWARE.
Limitation of Liability
KEITHLEY INSTRUMENTS SHALL IN NO EVENT, REGARDLESS OF CAUSE, ASSUME RESPONSIBILITY FOR
OR BE LIABLE FOR: (1) ECONOMICAL, INCIDENTAL, CONSEQUENTIAL, INDIRECT, SPECIAL, PUNITIVE OR
EXEMPLARY DAMAGES, WHETHER CLAIMED UNDER CONTRACT, TORT OR ANY OTHER LEGAL THEORY,
(2) LOSS OF OR DAMAGE TO THE CUSTOMER'S DATA OR PROGRAMMING, OR (3) PENALTIES OR PENALTY
CLAUSES OF ANY DESCRIPTION OR INDEMNIFICATION OF THE CUSTOMER OR OTHERS FOR COSTS, DAM-
AGES, OR EXPENSES RELATED TO THE GOODS OR SERVICES PROVIDED UNDER THIS WARRANTY.
Keithley Instruments, Inc. 28775 Aurora Road • Cleveland, Ohio 44139 • 440-248-0400 • Fax: [phone]
1-888-KEITHLEY (534-8453) • www.keithley.com
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4/02
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PIO-24 Parallel Digital Interface Board
User’s Guide
©1991, Keithley Instruments, Inc.
All rights reserved.
Cleveland, Ohio, U.S.A.
Third Printing, April 2001
Part Number: 64230 Rev. C
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Manual Print History
The print history shown below lists the printing dates of all Revisions and Addenda
created for this manual. The Revision Level letter increases alphabetically as the man-
ual undergoes subsequent updates. Addenda, which are released between Revisions,
contain important change information that the user should incorporate immediately
into the manual. Addenda are numbered sequentially. When a new Revision is created,
all Addenda associated with the previous Revision of the manual are incorporated into
the new Revision of the manual. Each new Revision includes a revised copy of this
print history page.
Revision A (Part Number 64230) ...................................................................................... July 1991
Revision B (Part Number 64230) ...................................................................................... July 1999
Revision C (Part Number 64230) .................................................................................... April 2001
All Keithley product names are trademarks or registered trademarks of Keithley Instruments, Inc.
Other brand names are trademarks or registered trademarks of their respective holders.
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The following safety precautions should be observed before using this product and any associated instrumentation.
Although some instruments and accessories would normally be used with non-hazardous voltages, there are situations
where hazardous conditions may be present.
This product is intended for use by qualified personnel who recognize shock hazards and are familiar with the safety
precautions required to avoid possible injury. Read and follow all installation, operation, and maintenance information
carefully before using the product. Refer to the manual for complete product specifications.
If the product is used in a manner not specified, the protection provided by the product may be impaired.
The types of product users are:
Responsible body is the individual or group responsible for the use and maintenance of equipment, for ensuring that
the equipment is operated within its specifications and operating limits, and for ensuring that operators are adequately
trained.
Operators use the product for its intended function. They must be trained in electrical safety procedures and proper use
of the instrument. They must be protected from electric shock and contact with hazardous live circuits.
Maintenance personnel perform routine procedures on the product to keep it operating properly, for example, setting
the line voltage or replacing consumable materials. Maintenance procedures are described in the manual. The proce-
dures explicitly state if the operator may perform them. Otherwise, they should be performed only by service personnel.
Service personnel are trained to work on live circuits, and perform safe installations and repairs of products. Only
properly trained service personnel may perform installation and service procedures.
Keithley products are designed for use with electrical signals that are rated Installation Category I and Installation
Category II, as described in the International Electrotechnical Commission (IEC) Standard IEC 60664. Most mea-
surement, control, and data I/O signals are Installation Category I and must not be directly connected to mains voltage
or to voltage sources with high transient over-voltages. Installation Category II connections require protection for high
transient over-voltages often associated with local AC mains connections. Assume all measurement, control, and data
I/O connections are for connection to Category I sources unless otherwise marked or described in the Manual.
Exercise extreme caution when a shock hazard is present. Lethal voltage may be present on cable connector jacks or
test fixtures. The American National Standards Institute (ANSI) states that a shock hazard exists when voltage levels
greater than 30V RMS, 42.4V peak, or 60VDC are present. A good safety practice is to expect that hazardous volt-
age is present in any unknown circuit before measuring.
Operators of this product must be protected from electric shock at all times. The responsible body must ensure that
operators are prevented access and/or insulated from every connection point. In some cases, connections must be ex-
posed to potential human contact. Product operators in these circumstances must be trained to protect themselves from
the risk of electric shock. If the circuit is capable of operating at or above 1000 volts, no conductive part of the circuit
may be exposed.
Do not connect switching cards directly to unlimited power circuits. They are intended to be used with impedance
limited sources. NEVER connect switching cards directly to AC mains. When connecting sources to switching cards,
install protective devices to limit fault current and voltage to the card.
Before operating an instrument, make sure the line cord is connected to a properly grounded power receptacle. Inspect
the connecting cables, test leads, and jumpers for possible wear, cracks, or breaks before each use.
S
afety Precautions
5/02
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When installing equipment where access to the main power cord is restricted, such as rack mounting, a separate main
input power disconnect device must be provided, in close proximity to the equipment and within easy reach of the
operator.
For maximum safety, do not touch the product, test cables, or any other instruments while power is applied to the cir-
cuit under test. ALWAYS remove power from the entire test system and discharge any capacitors before: connecting
or disconnecting cables or jumpers, installing or removing switching cards, or making internal changes, such as in-
stalling or removing jumpers.
Do not touch any object that could provide a current path to the common side of the circuit under test or power line (earth)
ground. Always make measurements with dry hands while standing on a dry, insulated surface capable of withstanding the
voltage being measured.
The instrument and accessories must be used in accordance with its specifications and operating instructions or the
safety of the equipment may be impaired.
Do not exceed the maximum signal levels of the instruments and accessories, as defined in the specifications and op-
erating information, and as shown on the instrument or test fixture panels, or switching card.
When fuses are used in a product, replace with same type and rating for continued protection against fire hazard.
Chassis connections must only be used as shield connections for measuring circuits, NOT as safety earth ground con-
nections.
If you are using a test fixture, keep the lid closed while power is applied to the device under test. Safe operation re-
quires the use of a lid interlock.
If or is present, connect it to safety earth ground using the wire recommended in the user documentation.
The symbol on an instrument indicates that the user should refer to the operating instructions located in the manual.
The symbol on an instrument shows that it can source or measure 1000 volts or more, including the combined
effect of normal and common mode voltages. Use standard safety precautions to avoid personal contact with these
voltages.
The WARNING heading in a manual explains dangers that might result in personal injury or death. Always read the
associated information very carefully before performing the indicated procedure.
The CAUTION heading in a manual explains hazards that could damage the instrument. Such damage may invalidate
the warranty.
Instrumentation and accessories shall not be connected to humans.
Before performing any maintenance, disconnect the line cord and all test cables.
To maintain protection from electric shock and fire, replacement components in mains circuits, including the power
transformer, test leads, and input jacks, must be purchased from Keithley Instruments. Standard fuses, with applicable
national safety approvals, may be used if the rating and type are the same. Other components that are not safety related
may be purchased from other suppliers as long as they are equivalent to the original component. (Note that selected parts
should be purchased only through Keithley Instruments to maintain accuracy and functionality of the product.) If you
are unsure about the applicability of a replacement component, call a Keithley Instruments office for information.
To clean an instrument, use a damp cloth or mild, water based cleaner. Clean the exterior of the instrument only. Do
not apply cleaner directly to the instrument or allow liquids to enter or spill on the instrument. Products that consist
of a circuit board with no case or chassis (e.g., data acquisition board for installation into a computer) should never
require cleaning if handled according to instructions. If the board becomes contaminated and operation is affected,
the board should be returned to the factory for proper cleaning/servicing.
!
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Table of Contents
1 Introduction
General description .................................................................... 1-2
Product change notice ................................................................ 1-4
Applications ............................................................................... 1-5
Accessories ................................................................................. 1-5
Specifications ............................................................................. 1-6
Connections ................................................................................ 1-7
2 Installation
General ....................................................................................... 2-2
Unpacking and inspecting .......................................................... 2-2
Switch and jumper settings ........................................................ 2-2
Base address switch ............................................................ 2-3
J8 slot jumper ............................................................................. 2-4
Interrupt level selection ....................................................... 2-4
Installing and configuring DriverLINX for PIO-24 boards ....... 2-5
Before installing DriverLINX ............................................. 2-5
Selecting the DriverLINX components to install ................ 2-6
Installing DriverLINX ......................................................... 2-6
Configuration with DriverLINX ......................................... 2-7
Hardware installation ................................................................. 2-7
Using power from the PIO-24 .................................................... 2-8
3 I/O Address Map
General ....................................................................................... 3-2
4 Configuring DriverLINX
General ....................................................................................... 4-2
I/O bit tests ................................................................................. 4-4
General information ............................................................ 4-4
Output set test ..................................................................... 4-7
Input read test .................................................................... 4-11
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5 Programming
General ....................................................................................... 5-2
Control Byte ............................................................................... 5-2
Selecting an application programming interface ........................ 5-3
DriverLINX interface .......................................................... 5-4
Direct I/O application programming interface .................... 5-5
Installing the Direct I/O Driver ........................................... 5-5
Configuring the Direct I/O Driver ....................................... 5-6
Programming the Direct I/O Interface ................................. 5-6
6 Troubleshooting
General ....................................................................................... 6-2
Using the DriverLINX Event Viewer .................................. 6-2
Device initialization error messages .................................... 6-2
Problem isolation ........................................................................ 6-3
Testing the board and host computer .......................................... 6-5
Testing the accessory slot and I/O connections .......................... 6-5
Technical support ........................................................................ 6-6
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List of Illustrations
1 Introduction
Figure 1-1 PIO-24 block diagram ............................................................ 1-2
Figure 1-2 Poor implementation of monitoring a digital input ............... 1-4
Figure 1-3 Better implementation of monitoring a digital input ............. 1-5
Figure 1-4 I/O connector, rear view ......................................................... 1-7
2 Installation
Figure 2-1 Switch and jumper layout ...................................................... 2-3
Figure 2-2 Diagram of the base address switch (S2) ............................... 2-3
4 Configuring DriverLINX
Figure 4-1 An AIO Panel example .......................................................... 4-4
Figure 4-2 DIO channel tab example ...................................................... 4-5
Figure 4-3 Configuring the digital I/O channels as inputs and outputs ... 4-6
Figure 4-4 Configuring channel 0 for output bit pattern A ...................... 4-7
Figure 4-5 An AIO Panel example .......................................................... 4-8
Figure 4-6 Configuring the digital I/O channels as inputs and outputs ... 4-9
Figure 4-7 Configuring channel 0 for output bit pattern A ...................... 4-9
Figure 4-8 Configuring channel 0 for output bit pattern B .................... 4-10
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List of Tables
1 Introduction
Table 1-1 Specifications ......................................................................... 1-6
2 Installation
Table 2-1 I/O address map ..................................................................... 2-4
3 I/O Address Map
Table 3-1 PIO-24 locations .................................................................... 3-2
5 Programming
Table 5-1 Mode 0 control words and port directions ............................. 5-3
6 Troubleshooting
Table 6-1 Troubleshooting information ................................................. 6-3
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1
Introduction
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1-2 Introduction
General description
Figure 1-1
PIO-24 block diagram
Referring to the block diagram, the PIO-24 is a high-current, 24-line, parallel, dig-
ital I/O interface board for the IBM PC or PC-compatible. The board emulates an
8255 Programmable Peripheral Interface Control Word MODE 0. (While the Keithley
PIO-12 also uses an 8255 Programmable Peripheral Interface chip, it drives much less
current than the PIO-24.)
The PIO-24 and computer with DriverLINX software requires:
• an IBM PC or compatible AT (386, or Pentium CPU) with minimum of 2 MB
of memory
• at least one floppy disk drive, and one fixed disk drive
• Microsoft Windows 95/98, or Windows NT 4.0 or higher
• a compiler supporting Microsoft Windows development
• a mouse is highly recommended.
PC Bus
Data Bus
Buffer
Address
Decoder
Direction
Control
Rear Connector
Address
Selector
Switch
Interrupt
Level
Selector
D0
D7
Data
A0
A9
Address
IOR/
IOW/
IRQ2
IRQ7
Interrupt
P
O
W
E
R
PA
PB
PC
24 Lines of
Digital I/O
Interrupt Input
Interrupt Enable
+5V
-5V
+12V
-12V
Common
L
A
T
C
H
D
R
I
V
E
R
B
U
F
F
E
R
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Introduction 1-3
The following software is available for operating PIO-24 boards:
•
PIO-24 standard software package — Shipped with PIO-24 boards.
Includes DriverLINX for Microsoft Windows 95/98 or Windows NT and
function libraries for writing application programs under Windows in a high-
level language such as Microsoft Visual C++, Microsoft Visual Basic; Borland
Delphi support files; utility programs; and language-specific example
programs.
•
DriverLINX — the high-performance real-time data-acquisition device driv-
ers for Windows application development including:
•
DriverLINX API DLLs and drivers supporting the PIO-24 hardware
• AIO Panel — A DriverLINX program that verifies the installation and
configuration of DriverLINX to your PIO-24 board and demonstrates
several virtual bench-top instruments
•
Learn DriverLINX — an interactive learning and demonstration program
for DriverLINX that includes a Digital Storage Oscilloscope
•
Source Code — for the sample programs
•
DriverLINX Application Programming Interface files — for the PIO-24
compiler
•
DriverLINX On-line Help System — provides immediate help as you
operate DriverLINX
•
Supplemental Documentation — on DriverLINX installation and config-
uration; analog and digital I/O programming; counter/timer program-
ming; technical reference; and information specific to the PIO-24
hardware
.
The major features of PIO-24 board are as follows:
• Three TTL/CMOS-compatible, digital I/O ports: PA, PB, and PC. PA and PB
are both byte wide (8-bit) and are usable as inputs or outputs. PC is also byte
wide but is adaptable for use as two separate 4-bit ports: PC Lower and PC
Upper, each of which is usable as an input or output.
• An interrupt input channel with a corresponding interrupt-enable line. Inter-
rupts can be directed to any of six interrupt levels available on the PC Bus.
PIO-24 interrupts are unlatched and edge-sensitive.
• The PIO-24 performs a 10-bit I/O address decode and communicates with the
PC Bus as an 8-bit peripheral. The address map uses four consecutive I/O
addresses. Multiple PIO-24s may be installed in a computer at different Base
Addresses.
• +5V, +12V, and -12V power levels from the PC supplies are provided on the
rear connector. The 37-pin D connector of the PIO-24 is pin-compatible with
the PIO-12 and is usable with all the accessories of the PIO-12.
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1-4 Introduction
Product change notice
A component change was implemented in March 1999, reducing the input load
current of the PIO-24 digital I/O card for improved consistency. The input load cur-
rent on the newly designed board is now
≤ -2µA, which continues to meet the product
specification of
≤ -450µA. This change was made because some devices having low
drive current, such as the ERB-24, were accidentally being turned on when power
was first applied to the PIO-24. The specific change involved changing parts U3, U6,
and U9, the digital input latches. The older design used 74LS373 octal tri-state
latches, which had a higher input load current than the 74HCT373 parts that are now
being used. In existing designs using the PIO-24, this reduction in input load current
will generally cause no problems. However, if the existing design depends on this
input load current being near the -450µA limit, this change is important. The reduc-
tion in input load current reduces the possibility of the input state being driven high if
the input is floating. Figure 1-2 shows an application monitoring a contact switch that
would be a problem as a result of the new design, and Figure 1-3 shows the correct
implementation of this application that would work with either design.
Figure 1-2
Poor implementation of monitoring a digital input
In Figure 1-2, the digital input would probably float high with an older design
board because of the higher input load current. When the switch is closed, the input
will be pulled low. While this would work on an older design of the PIO-24, this is a
poor implementation because the input load current can vary from one board to the
next. In the case of a new design board, this would not work because of the lower load
current.
PIO-24
<450uA
R=unknown
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Introduction 1-5
Figure 1-3
Better implementation of monitoring a digital input
In Figure 1-3, the digital input is guaranteed to be pulled high because of the 10k
ohm resistor. This implementation would work on both the old and new design of the
PIO-24 and is the preferred implementation to avoid dependence on a specific level of
input load current.
Applications
Applications for the PIO-24 include all parallel digital I/O activities such as
communicating with peripherals, operating relays, reading switch inputs, etc.
Keithley Instruments applications engineers welcome inquiries into installation,
operation, and applications of the PIO-24. To inquire, dial [phone] and ask for
technical support.
Accessories
Accessory products available for the PIO-24 include the SFC-37 Mating Connec-
tor, the C-1800 Flat Cable, the STA-U Screw Connector Panel, and the mechanical
and solid-state relay board Models ERB-24, ERA-01, SRA-01, and SSIO-24.
PIO-24
+5 Volts
10k ohm
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1-6 Introduction
Specifications
Table 1-1
Specifications
Parameters Minimum Maximum
LOGIC INPUTS & OUTPUTS
Input low voltage -0.5 +0.8V
Input high voltage 2.0 5.0V
Input low load current PA, PB & PC - -0.4mA
INTERRUPT ENABLE/
(10Kohm Pull-up Resistor included)
- -0.9mA
INTERRUPT - 0.4mA
Input Load High Current PA, PB, PC - 70µa
INTERRUPT ENABLE/ - 20µa
INTERRUPT - 20µa
Output low voltage PA, PB, PC
(Isink = 64mA)
- 0.55V
Output high voltage PA, PB, PC:
Isource = 15mA 2.0V
Isource = 3mA 2.7V
Bus Loading Power Consumption 400mA typ. @ +5V
ENVIRONMENTAL
Operating Temperature Range: 0˚ to 70˚C
Storage Temperature Range: -40˚ to 100˚C
Humidity: 0 to 90%
Noncondensing
Size: Half Slot
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Introduction 1-7
Connections
Figure 1-4 shows a rear view of the 37-pin D male I/O connector. The mating con-
nector is a 37-pin D female (Part No. SFC-37).
Figure 1-4
I/O connector, rear view
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
PC Power SuppliesPB Port
PA PortPC Port
Interrupt Enable
Interrupt Input
Dig. Com.
+5V
Dig. Com.
+5V
Dig. Com.
+12V
Dig. Com.
-12V
Dig. Com.
-5V
Dig. Com.
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
PA0
PA1
PA2
PA3
PA4
PA5
PA6
PA7
PC0
PC1
PC2
PC3
PC4
PC5
PC6
PC7
Upper Lower
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