Page 1
NI Vision
NI PCIe-8255R User Manual
IEEE 1394a and IEEE 1394b Interface Device with Reconfigurable I/O
NI PCIe-8255R User Manual
February 2007
371911C-01
Page 2
Support
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Important Information
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The NI PCIe-8255R is warranted against defects in materials and wo rkmanship for a period of one year from the date of shipment, as evidenced
by receipts or other documentation. National Instruments will, at its option, repair or replace equipment that proves to be defective during the
warranty period. This warranty includes parts and labor.
The media on which you receive National Instruments software are warranted not to fail to execute programming instructions, due to defects in
materials and workmanship, for a period of 90 days from date of shipment, as evidenced by receipts or other documentation. National Instruments
will, at its option, repair or replace software media that do not execute programming instruc tions if National Instruments receives notice of such defects
during the warranty period. National Instruments does not warrant that the operation of the software shall be uninterrupted or error free.
A Return Material Authorization (RMA) number must be obtained from the factory and clearly marked on the outside of the package before any
equipment will be accepted for warranty work. National Instruments will pay the shipping costs of returning to the owner parts which are covered by
warranty.
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the event that technical or typographical errors exist, National Instruments reserves the right to make changes to subsequent editions of this document
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Page 4
Compliance
Compliance with FCC/Canada Radio Frequency Interference
Regulations
Determining FCC Class
The Federal Communications Commission (FCC) has rules to protect wireless communications from interference. The FCC
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All Class A products display a simple warning statement of one paragraph in length regarding interference and undesired
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FCC/DOC Warnings
This equipment generates and uses radio frequency energy and, if not installed and used in strict accordance with the instructions
in this manual and the CE marking Declaration of Conformity*, may cause interference to radio and television reception.
Classification requirements are the same for the Federal Communications Commission (FCC) and the Canadian Department
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Changes or modifications not expressly approved by NI could void the user’s authority to operate the equipment under the
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This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to part 15 of the FCC
Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated
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Compliance with EU Directives
Users in the European Union (EU) should refer to the Declaration of Conformity (DoC) for information* pertaining to the
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information. To obtain the DoC for this product, visit
and click the appropriate link in the Certification column.
* The CE marking Declaration of Conformity contains important supplementary information and instructions for the user or
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ni.com/certification, search by model number or product line,
Page 5
Conventions
The following conventions are used in this manual:
» The» symbol leads you through nested menu items and dialog box options
to a final action. The sequence File»Page Setup»Options directs you to
pull down the File menu, select the Page Setup item, and select Options
from the last dialog box.
This icon denotes a note, which alerts you to important information.
This icon denotes a caution, which advises you of precautions to take to
avoid injury, data loss, or a system crash.
bold Bold text denotes items that you must select or click in the software, such
as menu items and dialog box options. Bold text also denotes parameter
names.
italic Italic text denotes variables, emphasis, a cross-reference, or an introduction
to a key concept. Italic text also denotes text that is a placeholder for a word
or value that you must supply.
monospace Text in this font denotes text or characters that you should enter from the
keyboard, sections of code, programming examples, and syntax examples.
This font is also used for the proper names of disk drives, paths, directories,
programs, subprograms, subroutines, device names, functions, operations,
variables, filenames, and extensions.
NI 8255R NI 8255R refers to the NI PCIe-8255R interface device.
Page 6
Contents
Chapter 1
Introduction
Software Overview ........................................................................................................1-1
Vision Builder for Automated Inspection .......................................................1-2
Vision Development Module ..........................................................................1-2
IEEE 1394 and the NI 8255R ........................................................................................1-3
Functional Overview......................................................................................................1-3
Start Conditions .............................................................................................................1-4
Acquisition Window Control.........................................................................................1-5
Chapter 2
Hardware Overview
Digital I/O .....................................................................................................................2-1
RIO and the LabVIEW FPGA Module..........................................................................2-1
TTL Inputs and Outputs.................................................................................................2-2
Isolated Inputs and Outputs ...........................................................................................2-3
I/O for Normal Operation ..............................................................................................2-5
Trigger Inputs ..................................................................................................2-5
Timed Pulse Output.........................................................................................2-5
Trigger Change Detectors................................................................................2-8
Quadrature Encoder.........................................................................................2-8
Product Selection Port .....................................................................................2-9
General-Purpose I/O........................................................................................2-10
I/O for Fault Conditions ..................................................................................2-11
Initiating a Timed Pulse ....................................................................2-6
Pulse Modes ......................................................................................2-6
Pulse Delay .......................................................................................2-7
Pulse Width .......................................................................................2-7
Trigger Polarity .................................................................................2-7
Using ISO Input 5 as a Latch............................................................2-9
General-Purpose Inputs.....................................................................2-10
General-Purpose Outputs ..................................................................2-10
Shutdown ..........................................................................................2-11
Watchdog Timer ...............................................................................2-12
© National Instruments Corporation ix NI PCIe-8255R User Manual
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Contents
Considerations When Connecting the Digital I/O......................................................... 2-13
Wiring an Isolated Input to a Sourcing Output Device................................... 2-13
Wiring an Isolated Output to an External Load .............................................. 2-14
Protecting Inductive Loads ............................................................................. 2-15
Transmission Line Effects .............................................................................. 2-16
Chapter 3
Signal Connections
Connectors..................................................................................................................... 3-2
IEEE 1394b Connector ................................................................................... 3-2
ATX Connector............................................................................................... 3-2
General-Purpose Digital I/O ........................................................................... 3-3
Cabling ..........................................................................................................................3-8
IEEE 1394 Camera Cables.............................................................................. 3-8
I/O Terminal Block ......................................................................................... 3-8
NI Vision I/O Terminal Block and Prototyping Accessory............................ 3-8
Power Requirements...................................................................................................... 3-9
Isolated Outputs Power Connection................................................................ 3-9
Appendix A
Technical Support and Professional Services
Glossary
Index
NI PCIe-8255R User Manual x ni.com
Page 8
Introduction
The NI PCIe-8255R (NI 8255R) is a OHCI compliant IEEE 1394a and
IEEE 1394b interface device for PCI Express (PCIe) with reconfigurable
I/O (RIO).
The NI 8255R device ships with NI Vision Acquisition Software, which
contains all of the drivers in the NI Vision product line. With NI Vision
Acquisition Software, you can quickly and easily start your applications
without having to program the device at the register level.
The NI 8255R includes TTL inputs and outputs for triggering, and isolated
inputs and outputs for connecting to external devices, such as lighting
controllers, proximity sensors, and quadrature encoders.
Behind the digital I/O of the NI 8255R is an FPGA which has been
preconfigured with the functionality required for most common machine
vision tasks. However, if the factory configured functionality does not
fulfill your requirements, the FPGA is user-configurable using the
LabVIEW FPGA Module. The NI 8255R provides a convenient 44-pin
D-SUB connector on its front panel to access the digital I/O.
1
For detailed specifications of the NI 8255R, refer to the Specifications
section of Getting Started with the NI PCIe-8255R.
Software Overview
Programming the NI 8255R requires two drivers to control the hardware:
NI-IMAQdx and NI-IMAQ I/O. Both drivers are included with the
NI Vision Acquisition Software.
NI-IMAQdx controls the IEEE 1394 cameras connected to the NI 8255R.
NI-IMAQdx has an extensive library of functions you can call and handles
the communication between the computer and the image acquisition
device, such as programming interrupts and camera control. NI-IMAQ I/O
provides functions to control the I/O on the NI 8255R.
National Instruments also offers the following application software
packages for analyzing and processing your acquired images. For detailed
© National Instruments Corporation 1-1 NI PCIe-8255R User Manual
Page 9
Chapter 1 Introduction
information about individual software packages, refer to the documentation
specific to each package.
Vision Builder for Automated Inspection
The NI Vision Builder for Automated Inspection (Vision Builder AI) is
configurable machine vision software that you can use to prototype,
benchmark, and deploy applications. Vision Builder AI does not require
programming, but is scalable to powerful programming environments.
Vision Builder AI allows you to easily configure and benchmark a
sequence of visual inspection steps, as well as deploy the visual inspection
system for automated inspection. With Vision Builder AI, you can perform
powerful visual inspection tasks and make decisions based on the results
of individual tasks. You also can migrate the configured inspection to
LabVIEW, extending the capabilities of the applications if necessary.
Vision Development Module
The NI Vision Development Module, which consists of NI Vision and
NI Vision Assistant, is an image acquisition, processing, and analysis
library of more than 270 functions for the following common machine
vision tasks:
• Pattern matching
• Particle analysis
•Gauging
• Taking measurements
• Grayscale, color, and binary image display
You can use the Vision Development Module functions individually or
in combination. With the Vision Development Module, you can acquire,
display, and store images, as well as perform image analysis and
processing. Using the Vision Development Module, imaging novices and
experts can program the most basic or complicated image applications
without knowledge of particular algorithm implementations.
As a part of the Vision Development Module, NI Vision Assistant is an
interactive prototyping tool for machine vision and scientific imaging
developers. With Vision Assistant, you can prototype vision applications
quickly and test how various image processing functions work.
Vision Assistant generates a Builder file, which is a text description
containing a recipe of the machine vision and image processing functions.
NI PCIe-8255R User Manual 1-2 ni.com
Page 10
Chapter 1 Introduction
This Builder file provides a guide you can use for developing applications
in any ADE, such as LabWindows
Vision Assistant machine vision and image processing libraries. Using the
LabVIEW VI creation wizard, Vision Assistant can create LabVIEW VI
diagrams that perform the prototype you created in Vision Assistant.
You can then use LabVIEW to add functionality to the generated VI.
IEEE 1394 and the NI 8255R
The NI 8255R uses FireWire® (IEEE 1394) technology. FireWire is a
cross-platform implementation of the high-speed serial data bus—defined
by the IEEE 1394-1995, IEEE 1394a-2000, and IEEE 1394b-2002
standards—that can move large amounts of data between computers and
peripheral devices. It features simplified cabling using twisted pairs, hot
swapping, and transfer speeds of up to 800 megabits per second. You can
support up to 63 devices on the high-speed bus with IEEE 1394.
The NI 8255R provides two direct-connect IEEE 1394b bilingual ports,
which support IEEE 1394a and IEEE 1394b devices
devices can be added using IEEE 1394 hubs. The NI 8255R can acquire
images from IEEE 1394 cameras conforming to the IIDC 1394-based
Digital Camera Specification, Version 1.30 and later.
The IEEE 1394 bus provides a fixed amount of bandwidth that is shared
between the two IEEE 1394 ports on the NI 8255R. These ports provide
direct connection for up to two DCAM-compliant IEEE 1394 cameras,
depending on the amount of bandwidth each camera requires. Higher frame
rates and larger image sizes require a higher data transfer rate and use more
bandwidth.
™
/CVI™ or Visual Basic, using the
1
. More IEEE 1394
Functional Overview
The NI 8255R features a high-speed data path optimized for receiving and
formatting video data from IEEE 1394 cameras.
1
Using an IEEE 1394a device with the NI 8255R requires a 1394a-to-1394b cable or adapter.
© National Instruments Corporation 1-3 NI PCIe-8255R User Manual
Page 11
Chapter 1 Introduction
Figure 1-1 illustrates the key functional components of the NI 8255R.
ISO In
Start Conditions
The NI 8255R can start acquisitions in the following ways:
• Software control—You can configure the NI 8255R to capture a fixed
• Trigger control—You can start an acquisition by enabling external
TTL In
TTL Out
ISO Out
ISO Power
Connection
1394
Conns
1394
Power Conn
DSUB
PCIe
Conn
PCIe
to
PCI
Bridge
RIO
1394b
Controller
Figure 1-1. NI 8255R Block Diagram
number of frames. Use this configuration for capturing a single frame
or a sequence of frames.
trigger lines. Each of these inputs can start a video acquisition on a
rising or falling edge.
NI PCIe-8255R User Manual 1-4 ni.com
Page 12
Acquisition Window Control
You can configure the following parameter on the NI 8255R to control the
video acquisition window:
Acquisition window—The NI 8255R and the IIDC 1394-based Digital
Camera Specification allow you to specify a particular region of active
pixels and lines on a camera to acquire. In many cases, specifying a smaller
acquisition window will increase the maximum frame rate of the camera.
Valid acquisition windows, and their corresponding frame rates, are defined
by the camera.
Chapter 1 Introduction
© National Instruments Corporation 1-5 NI PCIe-8255R User Manual
Page 13
Hardware Overview
Digital I/O
The digital I/O on the NI 8255R is accessible through 2 TTL inputs, 10 TTL
outputs, 13 isolated inputs, and 4 isolated outputs.
You can use input signals as triggers, product selection ports, or to read
quadrature encoders. Uses for output signals include controlling camera
reset and exposure, controlling strobe lighting, outputting inspection
results, or communicating with PLCs. You can also define the functions of
digital input and output signals.
For information about how to use LabVIEW to implement specific digital
I/O functions, refer to the examples at
IMAQ IO.llb,
installed. For information about how to use C, Visual Basic, or .NET to
implement specific digital I/O functions, refer to the examples at
<National Instruments>\NI-IMAQ IO\Examples.
where <LabVIEW> is the location in which LabView is
2
<LabVIEW>\examples\IMAQ\
RIO and the LabVIEW FPGA Module
Behind the digital I/O of the NI 8255R is an FPGA which has been
preconfigured with the functionality required for most common machine
vision tasks. However, if the factory configured functionality does not
fulfill your requirements, the FPGA is user-configurable with the
LabVIEW FPGA Module. RIO allows you to develop custom FPGA
logic to add triggering, pulse-width modulation signals, or custom
communications protocols to your machine vision application.
Using National Instruments RIO hardware and the LabVIEW FPGA
Module, you can define your hardware without in-depth knowledge of
hardware design tools or hardware description languages (HDL). When
the signal requirements change, the LabVIEW code can be modified and
downloaded to the FPGA to change the I/O mix or type. This flexibility
allows you to reuse the same hardware and software at no extra expense.
© National Instruments Corporation 2-1 NI PCIe-8255R User Manual
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Chapter 2 Hardware Overview
NI-IMAQ I/O devices such as the the NI 8255R have 29 digital I/O lines
with built-in functionality for communicating with external devices, such
as reading quadrature encoder inputs, generating strobe pulses, and writing
to or reading from digital lines.
NI-IMAQ I/O devices have 15 digital input lines—13 optically isolated
lines and two dedicated TTL lines. There are 14 digital output lines—four
optically isolated lines and 10 dedicated TTL lines. Using these signals,
you can dynamically control your lighting or cameras, synchronize with a
conveyor belt, or communicate with relays that control solenoids and other
actuators.
For more information about using the LabVIEW FPGA Module to
implement custom FPGA logic, refer to the examples at
examples\IMAQ\IMAQ IO FPGA.llb
TTL Inputs and Outputs
TTL is a fast-switching 5 V digital signaling standard commonly used for
applications that require high precision, such as camera triggering. TTL
inputs and outputs do not require a separate power supply.
<LabVIEW>\
.
Caution Do not connect voltage or current sources to TTL outputs. Doing so could
damage the NI 8255R.
NI PCIe-8255R User Manual 2-2 ni.com
Page 15
Primary
Function
Input or
Output
Chapter 2 Hardware Overview
Table 2-1 summarizes the TTL inputs and outputs available on the
NI 8255R.
Table 2-1. NI 8255R TTL Inputs and Outputs
37-Pin
Terminal
Block
Number
Number
Available
Signal Names
44-Pin D-SUB
on NI 8255R
Pin Number
Trigger Input 2 TTL Input 0,
General Purpose
TTL Input 1,
General Purpose
Timed
Pulse
Output 6 TTL Output 1, Pulse 1
TTL Output 2, Pulse 2
TTL Output 3, Pulse 3
TTL Output 4, Pulse 4
TRIG 1, Pulse 5
TRIG 2, Pulse 6
*
*
1
16
4
6
7
18
24
9
Watchdog Output 1 TTL Output 0 3 4
General
Purpose
* TTL Input 0 and TTL Input 1 can also function as trigger change detectors.
Output 3 TTL Output 5
TTL Output 6
TTL Output 7
19
21
22
Isolated Inputs and Outputs
The isolated inputs and outputs on the NI 8255R have a separate ground
reference from the main NI 8255R supply, providing an easy means to
prevent ground loops that can introduce noise into a system. You can apply
signals up to 30 V to the isolated inputs. The voltage swing of the isolated
outputs is determined by the voltage you supply on the V
device.
pins of the
iso
1
2
5
7
8
20
—
—
21
23
24
Note V
Alternatively, V
can be supplied directly to the 44-pin D-SUB when using custom cabling.
iso
can be supplied directly to the 37-pin terminal block and to the NI Vision
iso
I/O Terminal Block and Prototyping Accessory with the 44-pin to 37-pin NI cable.
Note The isolated outputs have current-limiting protection circuitry. If this circuitry is
tripped, you can re-enable the outputs by removing the fault and restarting your computer.
© National Instruments Corporation 2-3 NI PCIe-8255R User Manual
Page 16
Chapter 2 Hardware Overview
Table 2-2 summarizes the isolated inputs and outputs available on the
NI 8255R.
Table 2-2. NI 8255R Isolated Inputs and Outputs
Primary
Function
Input or
Output
Number
Available
Signal Names
Trigger Input 3 TRIG 0
ISO Input 5
ISO Input 8
37-Pin
44-Pin D-SUB
on NI 8255R
Pin Number
*
†
*
11
35
40
Terminal
Block
Number
—
15
27
Quadrature
Encoder
External
Input 1 ISO Input 6
ISO Input 7
37
38
Input 1 ISO Input 11 44 31
Shutdown
Control
Product
Selection
†
Port
General
Purpose
General
Purpose
* TRIG 0, ISO Input 8, ISO Input 9, and ISO Input 10 can also function as trigger change detectors.
†
ISO Input 5 can also function as a latch for the product selection port.
Input 1 ISO Input 0
ISO Input 1
ISO Input 2
ISO Input 3
ISO Input 4
Input 2 ISO Input 9
ISO Input 10
Output 4 ISO Output 0
ISO Output 1
ISO Output 2
ISO Output 3
15
30
31
32
34
*
*
41
43
12
13
27
28
25
26
9
10
11
13
14
29
30
19
35
36
37
NI PCIe-8255R User Manual 2-4 ni.com
Page 17
I/O for Normal Operation
The following sections describe I/O functions that are available on the
NI 8255R during normal operation.
Trigger Inputs
Trigger inputs are available from both TTL inputs and isolated inputs. You
can use these trigger inputs to synchronize the NI 8255R with an external
event, such as the assertion of a signal generated by a proximity sensor or
a PLC, to indicate that an inspection item is passing in front of the camera.
The NI 8255R can use this input to initiate a timed pulse for camera control,
lighting control, encoder pulse counting, and result output timing.
For more information about creating a timed pulse output, refer to the
Timed Pulse Output section.
TTL Input 0, TTL Input 1, TRIG 0, ISO Input 6, ISO Input 7, ISO Input 8,
and ISO Input 11 can alternatively function as general-purpose inputs.
ISO Input 5 can alternatively function as a latch for the product selection
port.
Chapter 2 Hardware Overview
Timed Pulse Output
The NI 8255R is capable of timed pulse output on six different digital
outputs, which provides precise control over time-critical signals, such as
camera exposure. This section describes the various uses for the timed
pulse output and the parameters you can set to control these outputs.
Uses for timed pulse output include controlling camera reset and exposure,
controlling strobe lighting, operating plungers on an assembly line, and
communicating with PLCs. You can configure the start of the pulse output
generation to occur from software or from a rising or falling edge of a
trigger input.
In addition to controlling the timing of pulse output, you can also configure
the polarity of the output signal, resulting in a high-true or low-true signal.
Based on the polarity setting, the output signal asserts after the appropriate
delay time and de-asserts after the configured pulse width. You can set the
delay time in microseconds or in quadrature encoder counts from the start
signal—either a hardware trigger or a software command. Width is always
configured in microseconds.
© National Instruments Corporation 2-5 NI PCIe-8255R User Manual
Page 18
Chapter 2 Hardware Overview
Initiating a Timed Pulse
Each timed pulse generator has a trigger input that specifies whether to wait
on a particular trigger input to generate the pulse or to immediately
generate the pulse when software sets the pulse mode to Start in LabVIEW
or imaqIOPulseStart in C, Visual Basic, and .NET.
If the trigger input is set to Immediate in LabVIEW or using a None status
signal in C and Visual Basic, the pulse generation occurs as soon as the
pulse mode is set to Start in LabVIEW or imaqIOPulseStart in C and
Visual Basic. After generating a pulse, it immediately generates another
pulse until the pulse generation is stopped. If the trigger input is set to one
of the hardware trigger inputs, the timed pulse output waits for an assertion
edge on the appropriate trigger input. After generating a pulse it waits for
another trigger before generating another pulse. The assertion edge is
configurable based on the trigger polarity parameter. It then generates one
pulse and rearms to wait for the next trigger. In either case, the pulse output
generation stops and resets if the pulse mode parameter is set to Stop in
LabVIEW or imaqIOPulseStop in C and Visual Basic.
Figure 2-1 shows an output pulse when a trigger is selected.
Trigger
Input
Output
Pulse
Figure 2-1. Output pulse when trigger is selected
Pulse Modes
Each pulse generator has a Start and a Stop mode. Configure the pulse
generator when in Stop mode and then set it to Start mode.
NI PCIe-8255R User Manual 2-6 ni.com
Page 19
Chapter 2 Hardware Overview
Pulse Delay
Pulse delay is the amount of time between a trigger and the first (assertion)
edge of an output pulse. The pulse delay is configurable in units of
microseconds or quadrature encoder counts. If configured for
microseconds, available values are between 1 µs and 4,294,967,295 µs,
which is 4,294 seconds, or approximately 71 minutes. If the delay is
configured for quadrature encoder counts, the range of choices is 0 counts
to 4,294,967,295 counts.
Pulse Width
Pulse width is the amount of time between the first (assertion) edge of a
pulse and the second (deassertion) edge. Pulse width is configurable only
in microseconds from 1 µs to 4,294,967,295 µs.
Trigger Polarity
Each pulse generator can be individually configured for rising or falling
edge triggering. Even if multiple pulse generators are using the same
trigger, each can have different polarities.
Figure 2-2 shows the output of a pulse generator configured to look for a
rising edge trigger and output a high pulse with a microsecond delay and
width.
Delay
Trigger
Pulse
Figure 2-2. Pulse generator output when configured to detect rising edge trigger
© National Instruments Corporation 2-7 NI PCIe-8255R User Manual
Width
Page 20
Chapter 2 Hardware Overview
Figure 2-3 shows how to create a high and low pulse train with a
microsecond delay and width.
High Pulse Train
Low Pulse Train
Figure 2-3. Creating a high and low pulse train with a microsecond delay and width
Trigger Change Detectors
The NI 8255R is capable of detecting edges on various trigger lines and
latching this information for future retrieval. This feature is useful for
high-precision hardware-monitoring of the presence of external events
without the need for software polling. You can arm for the detection of a
rising edge, falling edge, or both on a supported trigger input line.
Supported trigger input lines include TTL Input 0, TTL Input 1,
ISO Input 8, ISO Input 9, ISO Input 10, and TRIG 0.
Quadrature Encoder
The quadrature encoder uses ISO Input 6 for its Phase A input and ISO
Input 7 for its Phase B input. Encoder speed is limited by the speed of the
isolated inputs. Each isolated input can change at a maximum rate of
100 kHz, making the maximum encoder rate 400,000 counts/s.
Delay Width
Software
Start
WidthDelay
The quadrature encoder can also be used as a timebase for the pulse
generation delay.
NI PCIe-8255R User Manual 2-8 ni.com
Page 21
Figure 2-4 shows a rising edge trigger and a low pulse with a quadrature
encoder delay and a microsecond width.
Figure 2-4. Rising edge trigger and a low pulse with a quadrature encoder delay and
Product Selection Port
The product selection port consists of a group of five isolated digital inputs
that the software running on the NI 8255R reads simultaneously. You can
program the NI 8255R to switch between up to 32 inspection sequences for
different parts on an assembly line.
Trigger
Low Pulse
Phase A
Phase B
Delay
Width
a microsecond width
Chapter 2 Hardware Overview
Based on the input to the product selection port, you can configure the
application software to run the appropriate inspection sequence. For
example, an upstream NI 8255R programmed for part classification might
drive the product selection port of a downstream NI 8255R. Alternatively,
a PLC with information about which part is being inspected can drive the
product selection port of the NI 8255R.
Using ISO Input 5 as a Latch
You can configure the product selection port to use ISO Input 5 as a latch.
A rising edge on ISO Input 5 can latch the data into a data register on the
NI 8255R. Before each inspection, the software checks the status of the
product select inputs and reads the most recent value latched into the
register. If ISO Input 5 is not used as a latch, it can be used as an extra bit
of data.
Note In Vision Builder AI, ISO Input 5 is always designated as a latch.
© National Instruments Corporation 2-9 NI PCIe-8255R User Manual
Page 22
Chapter 2 Hardware Overview
Table 2-3 lists the product selection ports.
Function External Connection
Data(5), rising edge latch ISO Input 5
Data(4) ISO Input 4
Data(3) ISO Input 3
Data(2) ISO Input 2
Data(1) ISO Input 1
Data(0) ISO Input 0
General-Purpose I/O
General-purpose inputs and outputs are available as both TTL and isolated
connections. The software running on the NI 8255R can read the inputs and
drive the outputs high or low at any time.
Table 2-3. NI 8255R Product Selection Ports
General-Purpose Inputs
The primary difference between general-purpose inputs and trigger inputs
is that you cannot use general-purpose inputs to initiate a timed pulse
generator. In an application, use the general-purpose inputs to get the status
of the inputs at a given point and not to synchronize the NI 8255R with an
external event.
An example of how to use general-purpose inputs is reading the status of a
general-purpose input as the first step in your inspection sequence and
recording that value as part of your inspection.
General-Purpose Outputs
The primary difference between general-purpose outputs and timed pulse
outputs is that the timing of general-purpose outputs is controlled by
software rather than hardware. As a result, timing of general-purpose
outputs changes as the inspection algorithm changes, which makes
general-purpose outputs less appropriate than timed outputs for camera
control, strobe light control, and other applications that require precise
timing.
NI PCIe-8255R User Manual 2-10 ni.com
Page 23
An example of using general-purpose outputs is driving a relay that turns
on an Inspection in Progress light for an operator to see while the
inspection sequence is running.
I/O for Fault Conditions
The NI 8255R recognizes the following fault conditions:
• External shutdown, when Shutdown mode is enabled
• Watchdog timer expiration
In the event of a fault condition, the behavior of the NI 8255R is dependent
on configuration settings of the software-enabled Shutdown mode. To
resume operation, address the fault condition and cycle power on your
computer.
Table 2-4 summarizes how user configuration affects the behavior of the
NI 8255R in the event of a fault condition.
Fault Condition Shutdown Enabled
Chapter 2 Hardware Overview
Table 2-4. Fault Condition Behavior
Outputs Change to
User-Defined States
External Shutdown On
Off
Watchdog On
Off
The following sections describe each fault condition.
Ye s
No
Ye s
No
Shutdown
Shutdown mode is a software-enabled feature that, when activated, allows
an external device to halt the NI 8255R processing operations.
Additionally, Shutdown mode allows you to specify user-defined
shutdown states for all fault conditions.
When Shutdown mode is enabled and the shutdown input signal,
ISO Input 11, turns off, the NI 8255R registers an external shutdown
condition. When a fault occurs, outputs operate according to user-defined
shutdown states. Each TTL output is configurable to drive high, drive low,
or tri-state, and each isolated output is on/off configurable.
© National Instruments Corporation 2-11 NI PCIe-8255R User Manual
Page 24
Chapter 2 Hardware Overview
Note For prototyping when equipment is unavailable, you can wire from V
iso
to
ISO Input 11 to simulate external equipment that indicates to the NI 8255R to operate
normally.
Watchdog Timer
The watchdog timer is a software configurable feature that can monitor
software on the NI 8255R and take action if the software is unresponsive.
The millisecond counter on the watchdog timer is configurable up to
65,534 ms, in 1 ms increments, before it expires.
Configure the watchdog timer to take one of the following actions when it
expires.
Caution Use the Indicator Only option only to test the watchdog timer. If software
becomes unresponsive, it cannot be relied upon to send notification to the host.
• Indicator Only—This option sends the expiration signal back to the
development machine through software. True indicates an expired
watchdog timer. False indicates an unexpired watchdog timer. The
expiration signal that indicates an expired watchdog timer continues to
assert until the watchdog timer is disarmed. Disarming the watchdog
timer resets the software indicator.
• TTL Output 0—This option outputs a signal on TTL Output 0. High
indicates that the watchdog timer has expired. Low indicates that the
watchdog timer has not expired. If the watchdog timer has expired, the
expiration signal continues to assert until the watchdog timer is
disarmed.
• Shutdown—If Shutdown mode is enabled, the outputs go to the
user-defined shutdown states.
NI PCIe-8255R User Manual 2-12 ni.com
Page 25
Chapter 2 Hardware Overview
Considerations When Connecting the Digital I/O
The isolated trigger inputs on the NI 8255R are current sinking and
optically isolated. The following are considerations you need to make when
connecting the digital I/O.
Wiring an Isolated Input to a Sourcing Output Device
You can wire an isolated input to a sourcing output device, as shown in the
following figure. Refer to Getting Started with the NI PCIe-8255R for
information about switching thresholds and current requirements.
Caution Do not apply a voltage greater than 30 VDC to the isolated inputs. Doing so could
damage the NI 8255R.
Figure 2-5 shows an example of connecting an isolated input to a sourcing
output device.
Sourcing
Output
Device
Viso
Input
Ciso
Figure 2-5. Connecting isolated input to a sourcing output device
© National Instruments Corporation 2-13 NI PCIe-8255R User Manual
Current
Limiter
NI 8255R
Vcc
Page 26
Chapter 2 Hardware Overview
Wiring an Isolated Output to an External Load
The digital output circuit sources current to external loads, as shown in
Figure 2-6.
Caution Do not draw more than 100 mA from 24 V or 30 V isolated outputs. Do not draw
more than 50 mA from 5 V isolated outputs.
Vcc
Viso
Digital Output
Ciso
NI 8255R
Figure 2-6. Digital output circuit sourcing current to external loads
Load
NI PCIe-8255R User Manual 2-14 ni.com
Page 27
Protecting Inductive Loads
When an inductive load, such as a relay or solenoid, is connected to an
output, a large counter-electromotive force may occur at switching time
due to energy stored in the inductive load. This flyback voltage can damage
the outputs and the power supply.
To limit flyback voltages at the inductive load, install a flyback diode across
the load. Mount the flyback diode as close to the load as possible. Use this
protection method if you connect any of the isolated outputs on the
NI 8255R to an inductive load.
Figure 2-7 shows an example of using an external flyback diode to protect
inductive loads.
Vcc
Chapter 2 Hardware Overview
Viso
Digital
Output
Load
Ciso
External
NI 8255R
Figure 2-7. An external flyback diode protecting inductive loads
© National Instruments Corporation 2-15 NI PCIe-8255R User Manual
Flyback
Diode for
Inductive Loads
Page 28
Transmission Line Effects
Transmission line effects can degrade the signals on the I/O cables and
cause instability. To minimize transmission line effects, use twisted pair
wires with a characteristic impedance of 118 Ω to connect external signals
to the 44-pin I/O D-SUB connector.
Figure 2-8 shows connections to the 44-pin D-SUB connector that
minimize transmission line effects.
44-Pin
DSUB
+5 V
118 Ω
62 kΩ
17
3
2
1
Receiving
Equipment
R
S
Transmitting
Equipment
TTL OUT(0)
TTL IN(0)
NI 8255R
Figure 2-8. Connections to the 44-pin D-SUB connector that minimize
transmission line effects
When connecting to TTL inputs on the NI 8255R, match the output
impedance of the transmitting device to the characteristic impedance of the
cable. For example, if the cable characteristic impedance is 118 Ω, make
R
equal to 118 Ω, as shown in the Figure 2-8.
s
Page 29
Signal Connections
Figure 3-1 shows the connectors and LEDs on the NI 8255R.
3
FOR PATENTS: NI.COM/PATENTS
R
5
5
2
8
-
e
I
C
P
I
N
NI PCIe-8255R
1
5
2
CA
M
IS
O
3
IEEE 1394b IEEE 1394b
4
DIGITAL I/O
!
1 IEEE 1394b Bilingual Connector
2 ISO/ATX Power Status LEDs
4 Digital I/O Connector
5 Camera Power ATX Connector
3 IEEE 1394b Bilingual Connector
Figure 3-1. NI 8255R Connectors
© National Instruments Corporation 3-1 NI PCIe-8255R User Manual
Page 30
Chapter 3 Signal Connections
Peripheral Connector Function
Table 3-1 summarizes the functions of the connectors on the NI 8255R.
Table 3-1. NI 8255R Connector Functions
IEEE 1394 9-pin IEEE 1394b bilingual
connector
Camera Power 4-pin ATX computer power
connector
Digital Input/Output 44-pin female high-density
D-SUB connector
Connectors
This section describes the connectors on the NI 8255R and includes pinouts
and signal descriptions.
IEEE 1394b Connector
The NI 8255R provides two direct-connect IEEE 1394b bilingual
connectors, which support IEEE 1394a and IEEE 1394b devices. The
connectors provide a reliable, high-frequency connection between the
NI 8255R device and up to two DCAM-compliant IEEE 1394 cameras.
To access the IEEE 1394b connectors on the NI 8255R device, use any
standard 9-pin IEEE 1394 cable.
Note You can use a 6-pin to 9-pin cable or adapter with IEEE 1394a cameras to connect
the cameras to the IEEE 1394b ports.
Power and data connection to
IEEE 1394 devices
Power from PC power supply to
IEEE 1394b connectors
External TTL I/O,
External isolated I/O,
Power for isolated outputs
ATX Connector
The ATX connector on the NI 8255R allows the 1394 devices that are
connected to the NI 8255R to draw power directly from the computer
power supply, instead of the PCI Express bus. The PCI Express bus has a
stricter current draw allowance than the computer power supply. Connect
the NI 8255R device to the computer power supply by connecting an
unused ATX power connector from within the computer chassis to the
ATX connector on the NI 8255R. The green LED on the front panel of the
NI 8255R device will illuminate when the ATX connector is connected to
the computer power supply and the computer is on.
NI PCIe-8255R User Manual 3-2 ni.com
Page 31
Note If possible, camera power should be provided through the ATX connector inside the
computer. If you cannot supply camera power through the ATX connector, camera power
is supplied by the PCI Express bus and should be limited to 3 W, shared by both ports.
General-Purpose Digital I/O
The 44-pin D-SUB connector provides access to the general-purpose
digital inputs and outputs and the isolated power supply. The
general-purpose digital I/O available on this connector includes 2 TTL
inputs, 10 TTL outputs, 13 isolated inputs, and 4 isolated outputs. In
addition to I/O, the 44-pin D-SUB connector provides access to V
C
for powering the isolated outputs with an external power supply. The
iso
orange LED on the front panel of the NI 8255R illuminates when power for
the isolated outputs is present. For easy connection to the digital I/O
connector, use the National Instruments digital I/O cable and the NI Vision
I/O Terminal Block and Prototyping Accessory.
Note The accessories available for use with the NI 8255R do not provide access to all
available I/O on the NI 8255R device. To access this I/O, you can create a custom cable
using a standard male 44-pin D-SUB connector.
For more information about the National Instruments digital I/O cable
and terminal blocks, refer to the Optional Equipment section of Getting
Started with the NI PCIe-8255R.
Chapter 3 Signal Connections
and
iso
Note Isolated inputs are compatible with 5 V logic if the external circuit meets the voltage
and current requirements listed in the Specifications section of Getting Started with the
NI PCIe-8255R.
Caution Do not draw more than 100 mA from 24 V or 30 V isolated outputs. Do not draw
more than 50 mA from 5 V isolated outputs.
© National Instruments Corporation 3-3 NI PCIe-8255R User Manual
Page 32
Chapter 3 Signal Connections
37-Pin
44-Pin D-SUB
on NI 8255R
Pin Number
Ter mi na l
Block
Number
Figure 3-2 illustrates the 44-pin D-SUB connector on the NI 8255R.
153044
11631
Figure 3-2. NI 8255R 44-Pin D-SUB Connector
Table 3-2 lists pin numbers, signal names, and signal descriptions for the
44-pin D-SUB connector on the NI 8255R and the 37-pin terminal block.
Table 3-2. Signal Connections
Signal
Name
Primary
Function
Alternate
Function
1 1 TTL Input 0 Pulse generator
trigger input
Trigger Change
Detector,
General-purpose
input
2 3 C Common-mode
—
signal of the
NI 8255R device
main power
3 4 TTL Output 0 Watchdog timer
output
4 5 TTL Output 1 Pulse generator
output
5 6 C Common-mode
General-purpose
output
General-purpose
output
—
signal of the
NI 8255R device
main power
NI PCIe-8255R User Manual 3-4 ni.com
Page 33
44-Pin D-SUB
on NI 8255R
Pin Number
37-Pin
Terminal
Block
Number
Table 3-2. Signal Connections (Continued)
Signal
Name
Primary
Function
Chapter 3 Signal Connections
Alternate
Function
6 7 TTL Output 2 Pulse generator
output
7 8 TTL Output 3 Pulse generator
output
8 6 C Common-mode
signal of the
NI 8255R device
main power
9 NC TRIG 2*/
TTL Output 8
10 17 V
iso
11 NC TRIG 0*/
ISO Input 12
Pulse generator
output
Isolated power —
Pulse generator
trigger input
12 19 ISO Output 0 General-purpose
output
13 35 ISO Output 1 General-purpose
output
14 34 C
iso
Isolated
common-mode
signal
General-purpose
output
General-purpose
output
—
General-purpose
output
Trigger Change
Detector,
General-purpose
input
—
—
—
15 9 ISO Input 0 Input port, Data(0) —
16 2 TTL Input 1 Pulse generator
trigger input
Trigger Change
Detector,
General-purpose
input
17 3 C Common-mode
—
signal of the
NI 8255R device
main power
© National Instruments Corporation 3-5 NI PCIe-8255R User Manual
Page 34
Chapter 3 Signal Connections
37-Pin
44-Pin D-SUB
on NI 8255R
Pin Number
Ter mi na l
Block
Number
Table 3-2. Signal Connections (Continued)
Signal
Name
Primary
Function
Alternate
Function
18 20 TTL Output 4 Pulse generator
output
19 21 TTL Output 5 General-purpose
output
20 22 C Common-mode
signal of the
NI 8255R device
main power
21 23 TTL Output 6 General-purpose
output
22 24 TTL Output 7 General-purpose
output
23 22 C Common-mode
signal of the
NI 8255R device
main power
24 NC TRIG 1*/
TTL Output 9
25 33 V
26 34 C
iso
iso
Pulse generator
output
Isolated power —
Isolated
common-mode
signal
General-purpose
output
—
—
—
—
—
General-purpose
output
—
27 36 ISO Output 2 General-purpose
—
output
28 37 ISO Output 3 General-purpose
—
output
29 12 C
iso
Isolated
—
common-mode
signal
30 10 ISO Input 1 Input port, Data(1) —
NI PCIe-8255R User Manual 3-6 ni.com
Page 35
Chapter 3 Signal Connections
Table 3-2. Signal Connections (Continued)
37-Pin
44-Pin D-SUB
on NI 8255R
Pin Number
Terminal
Block
Number
Signal
Name
Primary
Function
31 11 ISO Input 2 Input port, Data(2) —
32 13 ISO Input 3 Input port, Data(3) —
Alternate
Function
33 16 C
iso
Isolated
—
common-mode
signal
34 14 ISO Input 4 Input port, Data(4) —
35 15 ISO Input 5 Input port latch,
Data(5)
36 28 C
iso
Isolated
Pulse generator
trigger input
—
common-mode
signal
37 25 ISO Input 6 Quadrature encoder
Phase A
38 26 ISO Input 7 Quadrature encoder
Phase B
39 28 C
iso
Isolated
General-purpose
input
General-purpose
input
—
common-mode
signal
40 27 ISO Input 8 Pulse generator
trigger input
Trigger Change
Detector,
General-purpose
input
41 29 ISO Input 9 General-purpose
input
Trigger Change
Detector,
General-purpose
input
42 32 C
iso
Isolated
—
common-mode
signal
© National Instruments Corporation 3-7 NI PCIe-8255R User Manual
Page 36
Chapter 3 Signal Connections
37-Pin
44-Pin D-SUB
on NI 8255R
Pin Number
Ter mi na l
Block
Number
Table 3-2. Signal Connections (Continued)
Signal
Name
Primary
Function
Alternate
Function
43 30 ISO Input 10 General-purpose
input
44 31 ISO Input 11 User shutdown General-purpose
* TRIG 0, TRIG 1, and TRIG 2 are not available on the 37-pin terminal block or the NI Vision I/O Terminal Block and
Prototyping Accessory. If you need access to these signals, you can get them directly from the 44-pin D-SUB connector.
Trigger Change
Detector,
General-purpose
input
input
Cabling
IEEE 1394 Camera Cables
You can connect cameras to the NI 8255R using standard 9-pin IEEE 1394
cables. IEEE 1394 cables provide both a data path and power to your
camera. You can use a 6-pin to 9-pin cable or adapter with IEEE 1394a
cameras to connect the cameras to the IEEE 1394b ports.
I/O Terminal Block
National Instruments provides an I/O terminal block for the NI 8255R,
which can be mounted either horizontally or vertically. The I/O terminal
block breaks the signals out into easy-to-use screw terminals and comes
with a cable that connects directly to the 44-pin D-SUB connector on the
NI 8255R.
Note TRIG 0, TRIG 1, and TRIG 2 signals are not accessible through the standard 44- to
37-pin cable and I/O terminal block.
NI Vision I/O Terminal Block and Prototyping Accessory
Use the NI Vision I/O Terminal Block and Prototyping Accessory to
troubleshoot and prototype digital I/O applications for the NI 8254R,
NI 8255R, and the NI CVS-1450 Series compact vision system. The
NI Vision I/O Terminal Block and Prototyping Accessory provides
screw terminals for easy connections and LEDs for each signal.
NI PCIe-8255R User Manual 3-8 ni.com
Page 37
Note TRIG 0, TRIG 1, and TRIG 2 signals are not accessible through the standard 44- to
37-pin cable and NI Vision I/O Terminal Block and Prototyping Accessory.
Power Requirements
This section describes the power requirements of the NI 8255R.
Isolated Outputs Power Connection
The isolated output circuitry requires that a power source be connected to
the V
block, or the NI Vision I/O Terminal Block and Prototyping Accessory.
The isolated outputs power connection on the NI 8255R accommodates one
power supply. The V
for the NI 8255R. The C
the NI 8255R, as shown in Table 3-3.
and C
iso
pins on the 44-pin D-SUB connector, the 37-pin terminal
iso
iso
Table 3-3. Power Connection Terminals
Terminal Description
Chapter 3 Signal Connections
terminal provides the isolated power (5 to 30 VDC)
terminal provides the common-mode signal for
iso
V
iso
C
iso
Note The orange ISO LED on the front panel of the NI 8255R device will illuminate when
V
and C
iso
are properly connected to an external power supply.
iso
Isolated power (5 to 30 VDC)
Isolated common-mode signal
© National Instruments Corporation 3-9 NI PCIe-8255R User Manual
Page 38
Technical Support and
Professional Services
Visit the following sections of the National Instruments Web site at
ni.com for technical support and professional services:
• Support—Online technical support resources at
include the following:
– Self-Help Resources—For answers and solutions, visit the
award-winning National Instruments Web site for software drivers
and updates, a searchable KnowledgeBase, product manuals,
step-by-step troubleshooting wizards, thousands of example
programs, tutorials, application notes, instrument drivers, and
so on.
– Free Technical Support—All registered users receive free Basic
Service, which includes access to hundreds of Application
Engineers worldwide in the NI Discussion Forums at
ni.com/forums. National Instruments Application Engineers
make sure every question receives an answer.
For information about other technical support options in your
area, visit
ni.com/contact.
• Training and Certification—Visit
self-paced training, eLearning virtual classrooms, interactive CDs,
and Certification program information. You also can register for
instructor-led, hands-on courses at locations around the world.
• System Integration—If you have time constraints, limited in-house
technical resources, or other project challenges, National Instruments
Alliance Partner members can help. To learn more, call your local
NI office or visit
• Declaration of Conformity (DoC)—A DoC is our claim of
compliance with the Council of the European Communities using
the manufacturer’s declaration of conformity. This system affords
the user protection for electronic compatibility (EMC) and product
safety. You can obtain the DoC for your product by visiting
ni.com/certification.
ni.com/services or contact your local office at
ni.com/alliance.
A
ni.com/support
ni.com/training for
© National Instruments Corporation A-1 NI PCIe-8255R User Manual
Page 39
Appendix A Technical Support and Professional Services
• Calibration Certificate—If your product supports calibration,
you can obtain the calibration certificate for your product at
ni.com/calibration.
If you searched
ni.com and could not find the answers you need, contact
your local office or NI corporate headquarters. Phone numbers for our
worldwide offices are listed at the front of this manual. You also can visit
the Worldwide Offices section of
ni.com/niglobal to access the branch
office Web sites, which provide up-to-date contact information, support
phone numbers, email addresses, and current events.
NI PCIe-8255R User Manual A-2 ni.com
Page 40
Glossary
A
ADE Application development environment such as LabVIEW, Visual Basic,
or Microsoft Visual C.
B
bandwidth The range of frequencies present in a signal, or the range of frequencies to
which a measuring device can respond.
C
current The rate of flow of electric charge measured in amperes.
D
D-SUB A serial connector.
DCAM Digital camera.
E
exposure The amount of time that light reaches the image sensor.
F
falling edge An edge trigger occurs when the trigger signal passes through a specified
threshold. A slope that is negative to the trigger is specified as the falling
edge.
FireWire A high-speed serial interface invented by Apple Computer in 1989, also
known as IEEE 1394 or iLink.
© National Instruments Corporation G-1 NI PCIe-8255R User Manual
Page 41
Glossary
FPGA Field-programmable gate array. An FPGA is a semi-conductor device
which contains a large quantity of gates (logic devices), which are not
interconnected, and whose function is determined by a wiring list, which is
downloaded to the FPGA. The wiring list determines how the gates are
interconnected, and this interconnection is performed dynamically by
turning semiconductor switches on or off to enable the different
connections.
H
HDL Hardware description language. An example of an HDL is VHDL—a
language used to design digital circuitry.
hot swapping The act of removing or swapping a device when power is applied to it.
I
IEEE Institute of Electrical and Electronics Engineers.
IIDC IEEE 1394 Trade Association Instrumentation and Industrial Control
Working Group, Digital Camera Sub Working Group.
isolated A signal which has no electrical connection to the overall system power.
N
NI-IMAQdx Driver software for National Instruments IEEE 1394 and Gigabit Ethernet
interface devices.
P
pixel The fundamental picture element in a digital image. The smallest
resolvable rectangular area of an image, either on a screen or stored in
memory. Each pixel has its own brightness and color, usually represented
as red, green, and blue intensities.
PLC Programmable Logic Controller. An industrial computer used for factory
automation, process control, and manufacturing systems.
NI PCIe-8255R User Manual G-2 ni.com
Page 42
Glossary
proximity sensor Optical sensor which toggles an electrical signal when an object passes
near it.
Q
quadrature encoder An encoding technique for a rotating device where two tracks of
information are placed on the device, with the signals on the tracks offset
by 90 degrees from each other. This makes it possible to detect the direction
of the motion.
R
RIO Reconfigurable inputs and outputs.
rising edge An edge trigger occurs when the trigger signal passes through a specified
threshold. A slope that is positive to the trigger is specified as the rising
edge.
T
trigger Any event that causes or starts some form of data capture.
TTL Transistor-transistor logic. A digital circuit composed of bipolar transistors
wired in a certain manner. A typical medium-speed digital technology.
Nominal TTL logic levels are 0 and 5 V.
V
VDC Volts direct current.
voltage The electromotive force.
© National Instruments Corporation G-3 NI PCIe-8255R User Manual
Page 43
Index
A
acquisition window control, 1-5
ATX connector, 3-2
C
cabling, 3-8
calibration certificate (NI resources), A-2
connectors, 3-2
general-purpose digital I/O, 3-3
IEEE 1394a, 3-2
conventions used in the manual, vii
D
Declaration of Conformity (NI resources), A-1
diagnostic tools (NI resources), A-1
digital I/O
connection considerations, 2-13
overview, 2-1
documentation
conventions used in the manual, vii
NI resources, A-1
drivers (NI resources), A-1
G
general-purpose I/O, 2-10
general-purpose inputs, 2-10
general-purpose outputs, 2-10
H
help, technical support, A-1
I
I/O for fault conditions, 2-11
I/O for normal operation, 2-5
I/O terminal block, 3-8
IEEE 1394
camera cables, 3-8
connector, 3-2
connector function, 3-2
instrument drivers (NI resources), A-1
isolated inputs, 2-3
list of, 2-4
isolated outputs, 2-3
list of, 2-4
power connection, 3-9
E
examples (NI resources), A-1
F
FireWire, 1-3
FPGA, 2-1
© National Instruments Corporation I-1 NI PCIe-8255R User Manual
K
KnowledgeBase, A-1
L
LabVIEW FPGA Module, 2-1
latch, 2-9
Page 44
Index
N
National Instruments support and
services, A-1
NI 1427
software programming choices
NI Vision Builder for Automated
Inspection, 1-2
NI Vision Development Module, 1-2
NI 8255R
acquisition window control, 1-5
ATX connector, 3-2
cabling, 3-8
connection considerations, 2-13
connectors, 3-2
digital I/O overview, 2-1
general-purpose I/O, 2-10
I/O for fault conditions, 2-11
I/O for normal operation, 2-5
I/O terminal block, 3-8
IEEE 1394 camera cables, 3-8
isolated inputs, 2-3
isolated outputs, 2-3
LabVIEW FPGA Module, 2-1
NI Vision Terminal Block and
Prototyping Accessory, 3-8
power requirements, 3-9
product selection port, 2-9
quadrature encoder, 2-8
reconfigurable I/O, 2-1
signal connections, 3-1
start conditions, 1-4
trigger change detectors, 2-8
trigger inputs, 2-5
TTL inputs, 2-2
TTL outputs, 2-2
NI support and services, A-1
NI Vision Assistant, 1-2
NI Vision Terminal Block and Prototyping
Accessory, 3-8
P
power connection terminals, 3-9
power requirements, 3-9
product selection port, 2-9
programming examples (NI resources), A-1
protecting inductive loads, 2-15
Q
quadrature encoder, 2-8
R
reconfigurable I/O, 2-1
RIO. See reconfigurable I/O
S
signal connections, 3-1
software (NI resources), A-1
software programming choices
NI Vision Builder for Automated
Inspection, 1-2
NI Vision Development Module, 1-2
start conditions, 1-4
T
technical support, A-1
training and certification (NI resources), A-1
transmission line effects, 2-16
trigger change detectors, 2-8
trigger inputs, 2-5
troubleshooting (NI resources), A-1
TTL inputs, 2-2
TTL outputs, 2-2
NI PCIe-8255R User Manual I-2 ni.com
Page 45
W
Web resources, A-1
wiring
isolated input to sourcing output device,
2-13
isolated output to external load, 2-14
Index
© National Instruments Corporation I-3 NI PCIe-8255R User Manual
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