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warranty period. This warranty includes parts and labor.
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Compliance with FCC/Canada Radio Frequency Interference
Regulations
Determining FCC Class
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or Class B (for use in residential or commercial locations). All National Instruments (NI) products are FCC Class A products.
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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
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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
FCC Rules.
Class A
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*
The CE marking Declaration of Conformity contains important supplementary information and instructions for the user or
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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 8254R
NI 8254R refers to the NI PCI-8254R interface device.
Chapter 1
Vision Builder for Automated Inspection .......................................................1-2
Vision Development Module ..........................................................................1-2
Functional Overview......................................................................................................1-3
Chapter 2
Digital I/O......................................................................................................................2-1
Trigger Inputs..................................................................................................2-5
Pulse Width.......................................................................................2-7
Trigger Polarity.................................................................................2-7
Product Selection Port.....................................................................................2-8
General-Purpose I/O........................................................................................2-9
General-Purpose Inputs.....................................................................2-10
General-Purpose Outputs ..................................................................2-10
I/O for Fault Conditions ..................................................................................2-10
Shutdown ..........................................................................................2-11
Watchdog Timer ...............................................................................2-11
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Contents
Considerations When Connecting the Digital I/O......................................................... 2-12
Wiring an Isolated Output to an External Load .............................................. 2-13
Chapter 3
Connectors.....................................................................................................................3-2
Cabling .......................................................................................................................... 3-8
IEEE 1394 Camera Cables.............................................................................. 3-8
NI Vision I/O Terminal Block and Prototyping Accessory............................ 3-9
Power Requirements...................................................................................................... 3-9
Technical Support and Professional Services
Glossary
Index
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Introduction
The NI PCI-8254R is a OHCI compliant IEEE 1394a interface device with
reconfigurable I/O (RIO).
The NI 8254R 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 8254R 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 8254R 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 8254R provides a convenient 44-pin
D-SUB connector on its front panel to access the digital I/O.
For detailed specifications of the NI 8254R, refer to the Specifications
section of Getting Started with the NI PCI-8254R.
Software Overview
Programming the NI 8254R 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 has an extensive library of functions you can call and handles
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 8254R.
National Instruments also offers the following application software
packages for analyzing and processing your acquired images. For detailed
information about individual software packages, refer to the documentation
specific to each package.
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Vision Builder for Automated Inspection
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.
This Builder file provides a guide you can use for developing applications
in any ADE, such as LabWindows™/CVI™ or Visual Basic, using the
Vision Assistant machine vision and image processing libraries. Using the
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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 NI 8254R
The NI 8254R uses FireWire® (IEEE 1394) technology. FireWire is a
cross-platform implementation of the high-speed serial data bus—defined
by the IEEE 1394-1995 and IEEE 1394a-2000 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 400 megabits per second. You can support up to 63 devices
on the high-speed bus with IEEE 1394.
The IEEE 1394a standard offers up to 400 Mb/s bandwidth. The NI 8254R
provides two direct-connect IEEE 1394a ports, but more IEEE 1394
devices can be added using IEEE 1394 hubs. The NI 8254R 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 1394a ports on the NI 8254R. 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.
Functional Overview
The NI 8254R features a high-speed data path optimized for receiving and
formatting video data from IEEE 1394 cameras.
Figure 1-1 illustrates the key functional components of the NI 8254R.
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ISO In
TTL In
V2 FPGA
DSUB
PCI
CONN
PCI
Bridge
Dust
MITE
CPLD
TTL Out
ISO Out
Config ROM
ISO Power
Connection
1394A
Controller
1394
Conns
Power
Supply
+5 V, +1.5 V
1394
Power Conn
Figure 1-1. NI 8254R Block Diagram
Start Conditions
The NI 8254R can start acquisitions in the following ways:
•
Software control—The NI 8254R supports software control of
acquisition start. You can configure the NI 8254R to capture a fixed
number of frames. Use this configuration for capturing a single frame
or a sequence of frames.
•
Trigger control—You can start an acquisition by enabling external
trigger lines. Each of these inputs can start a video acquisition on a
rising or falling edge.
Acquisition Window Control
You can configure the following parameter on the NI 8254R to control the
video acquisition window:
•
Acquisition window—The NI 8254R 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.
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Hardware Overview
Digital I/O
The digital I/O functions on the NI 8254R are 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, change
detectors, 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 <LabVIEW>\examples\IMAQ\
IMAQ IO.llb, where <LabVIEW>is the location in which LabVIEW is
installed. For information about how to use C or Visual Basic to implement
specific digital I/O functions, refer to the examples at
<National Instruments>\NI-IMAQ IO\Examples\.
For more information about using the LabVIEW FPGA Module to
implement custom FPGA logic, refer to the examples at <LabVIEW>\
examples\IMAQ\IMAQ IO FPGA.llb, where <LabVIEW>is the location
to which you installed LabVIEW.
RIO and The LabVIEW FPGA Module
Behind the digital I/O of the NI 8254R is an FPGA which has been
preconfigured with the functionality required for most common machine
vision tasks. 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.
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Hardware Overview
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.
NI-IMAQ I/O devices such as the such as the NI 8254R, the NI 8255R, and
the NI CVS-1450 Series 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 isolated 24 V lines
and two dedicated TTL lines. There are 14 digital output lines—four
isolated 24 V 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.
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.
Caution Do not connect voltage or current sources to TTL outputs. Doing so could
damage the NI 8254R.
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Table 2-1 summarizes the TTL inputs and outputs available on the
NI 8254R.
Table 2-1. NI 8254R TTL Inputs and Outputs
44-Pin
D-SUB on
NI 8254R
Pin
37-Pin
Terminal
Block
Input
or
Output Available
Primary
Function
Number
Signal Names
Number
Number
Trigger
Input
2
TTL Input 0,
1
1
2
General Purpose*
TTL Input 1,
General Purpose*
16
Timed
Pulse
Output
6
TTL Output 1, Pulse 1
TTL Output 2, Pulse 2
TTL Output 3, Pulse 3
TTL Output 4, Pulse4
TRIG 1, Pulse 5
4
6
7
18
24
9
5
7
8
20
—
—
TRIG 2, Pulse 6
Watchdog
Output
Output
1
3
TTL Output 0
3
4
General
Purpose
TTL Output 5
TTL Output 6
TTL Output 7
19
21
22
21
23
24
* TTL Input 0 and TTL Input 1 can also function as trigger change detectors.
Isolated Inputs and Outputs
The isolated inputs and outputs on the NI 8254R have a separate ground
reference from the main NI 8254R 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 2-position isolated
outputs power connector.
Note Viso is referred to as V, and Ciso is referred to as C on the 2-position isolated outputs
power connector on the NI 8254R.
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.
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Table 2-2 summarizes the isolated inputs and outputs available on the
NI 8254R.
Table 2-2. NI 8254R Isolated Inputs and Outputs
44-Pin
D-SUB on
NI 8254R
Pin Number
37-Pin
Terminal
Block
Primary
Function
Input or
Output
Number
Available
Signal
Names
Number
Trigger
Input
3
TRIG 0*
ISO Input 5†
ISO Input 8*
11
35
40
—
15
27
Quadrature
Encoder
Input
Input
1
1
ISO Input 6
ISO Input 7
37
38
25
26
External
Shutdown
Control
ISO Input 11
44
31
Product
Selection
Port†
Input
1
ISO Input 0
ISO Input 1
ISO Input 2
ISO Input 3
ISO Input 4
15
30
31
32
34
9
10
11
13
14
General
Purpose
Input
2
4
ISO Input 9*
ISO Input 10*
41
43
29
30
General
Purpose
Output
ISO Output 0
ISO Output 1
ISO Output 2
ISO Output 3
12
13
27
28
198
35
36
37
*
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.
I/O for Normal Operation
The following sections describe I/O functions that are available on the
NI 8254R during normal operation.
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Trigger Inputs
Trigger inputs are available from both TTL inputs and isolated inputs. You
can use these trigger inputs to synchronize the NI 8254R with an external
event, such as the assertion of a signal generated by a proximity sensor or
The NI 8254R uses this input to initiate a timed pulse that can be used 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.
Timed Pulse Output
The NI 8254R 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.
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 and Visual Basic.
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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
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 resulting from trigger selection
Pulse Modes
Each pulse generator has a Start, Single Shot, and Stop mode. Configure
the pulse generator when in Stop mode. Then, set the pulse generator to
Start mode for continuous or rearmed pulses, and set it to Single Shot for a
pulse that should assert only once.
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.
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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.
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 width and
delay.
Delay
Width
Trigger
Pulse
Figure 2-2. Output pulse generator
Figure 2-3 shows how to create a high and low pulse train with a
microsecond delay and width.
High Pulse Train
Delay
Width
Delay
Width
Low Pulse Train
Software
Start
Figure 2-3. High and low pulse train
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Trigger Change Detectors
The NI 8254R 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.
The quadrature encoder can also be used as a timebase for the pulse
generation delay.
Figure 2-4 shows a rising edge trigger and a low pulse with a quadrature
encoder delay and a microsecond width.
Trigger
Low Pulse
Delay
Width
Phase A
Phase B
Figure 2-4. Rising edge trigger and low pulse
Product Selection Port
The product selection port consists of a group of five isolated digital inputs
that the software running on the NI 8254R reads simultaneously. You can
program the NI 8254R to switch between up to 32 (25) inspection
sequences for different parts on an assembly line.
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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 8254R programmed for part classification might
drive the product selection port of a downstream NI 8254R. Alternatively,
a PLC with information about which part is being inspected can drive the
product selection port of the NI 8254R.
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 8254R. Before each inspection, the software checks the status of 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.
Table 2-3 lists the product selection ports.
Table 2-3. NI 8254R Product Selection Ports
Function
Data(5), rising edge latch
Data(4)
External Connection
ISO Input 5
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 8254R can read the inputs and
drive the outputs high or low at any time.
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Chapter 2
Hardware Overview
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 8254R 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.
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 8254R 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 8254R 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 8254R in the event of a fault condition.
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Table 2-4. Fault Condition Behavior
Outputs Change to
User-Defined States
Fault Condition
External Shutdown
Shutdown Enabled
On
Off
Yes
No
Watchdog
On
Off
Yes
No
The following sections describe each fault condition.
Shutdown
Shutdown mode is a software-enabled feature that, when activated, allows
an external device to halt the NI 8254R 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 8254R 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.
Note For prototyping when equipment is unavailable, you can wire from V to
ISO Input 11 to simulate external equipment that indicates to the NI 8254R to operate
normally.
Watchdog Timer
The watchdog timer is a software configurable feature that can monitor
software on the NI 8254R 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.
© National Instruments Corporation
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Hardware Overview
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.
Considerations When Connecting the Digital I/O
The isolated trigger inputs on the NI 8254R 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
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 8254R.
Figure 2-5 shows an example of connecting an isolated input to a sourcing
output device.
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Chapter 2
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Sourcing
Output
Device
V
Vcc
Input
Current
Limiter
C
NI 8254R
Figure 2-5. Connecting isolated input to a sourcing output device
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.
V
Vcc
Digital Output
Load
C
NI 8254R
Figure 2-6. Digital output sources current to external loads
© National Instruments Corporation
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Chapter 2
Hardware Overview
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 8254R to an inductive load.
Figure 2-7 shows an example of using an external flyback diode to protect
inductive loads.
V
Vcc
Digital
Output
Load
C
External
Flyback
Diode for
NI 8254R
Inductive Loads
Figure 2-7. External flyback diode to protect inductive loads
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Chapter 2
Hardware Overview
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
TTL OUT(0)
3
2
Receiving
Equipment
+5 V
RS
TTL IN(0)
16
17
Transmitting
Equipment
NI 8254R
Figure 2-8. Connections to the 44-pin D-SUB connector
When connecting to TTL inputs on the NI 8254R, 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 Rs
equal to 118 Ω, as shown in the figure above.
© National Instruments Corporation
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NI PCI-8254R User Manual
3
Signal Connections
The following diagram shows the connectors on the NI 8254R.
NI PCI-8254R
IEEE-1394
1
2
3
V
C
5–30V
4
1
2
IEEE 1394a Connector
IEEE 1394a Connector
3
4
2-Position Isolated Outputs Power Connector
Digital I/O Connector
© National Instruments Corporation
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Chapter 3
Signal Connections
Table 3-1 summarizes the functions of the connectors on the NI 8254R.
Table 3-1. NI 8254R Connector Functions
Peripheral
Connector
Function
Isolated Output Power
2-position isolated outputs
power connector
Power for isolated outputs
IEEE 1394
6-pin IEEE 1394a connector
Power and data connection to
IEEE 1394 cameras
Digital Input/Output
Camera Power
44-pin female high-density
D-SUB
External TTL I/O; External
isolated I/O
4-pin computer power
Power from PC power supply
to IEEE 1394a connector
Connectors
This section describes the connectors on the NI 8254R and includes pinouts
and signal descriptions for each connector.
The isolated outputs power connector on the NI 8254R accommodates one
power supply. The V terminal provides the isolated output circuitry (5 to
30 VDC) for the NI 8254R. The C terminal provides the common-mode
signal for the NI 8254R.
Figure 3-1 illustrates the isolated outputs power connector on the
NI 8254R.
V C
Figure 3-1. NI 8254R Isolated Power Connector
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Table 3-2 summarizes the functions of the power connector terminals.
Table 3-2. Power Connector Terminals
Terminal
Description
V
C
Isolated power (5 to 30 VDC)
Isolated common-mode signal
IEEE 1394a Connector
The IEEE 1394a connectors on the NI 8254R provide a reliable,
high-frequency connection between the NI 8254R and up to
two DCAM-compliant IEEE 1394 cameras. To access the IEEE 1394a
connectors on the NI 8254R, use any standard 6-pin IEEE 1394 cable.
Note You can use a 4-pin to 6-pin converter cable with cameras that have their own
external power supply and do not require power from the IEEE 1394 bus.
General-Purpose Digital I/O
The 44-pin D-SUB connector provides access to the general-purpose
digital inputs and outputs. The general-purpose digital I/O available on this
connector includes 2 TTL inputs, 9 TTL outputs, 13 isolated inputs, and
4 isolated outputs. 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 8254R do not provide access to all
available I/O on the NI 8254R. 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 block, refer to the Optional Equipment section of Getting Started
with the NI PCI-8254R.
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 PCI-8254R.
© National Instruments Corporation
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Chapter 3
Signal Connections
Figure 3-2 illustrates the 44-pin D-SUB connector on the NI 8254R.
44 30 15
31 16
1
Figure 3-2. NI 8254R 44-Pin D-SUB Connector
Table 3-3 lists pin numbers, signal names, and signal descriptions for the
44-pin D-SUB connector on the NI 8254R and the 37-pin terminal block.
Caution Do not draw more than 500 mA combined from the V pins on the 44-pin D-SUB
connector. 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.
Table 3-3. Signal Connections
44-Pin D-SUB
on NI 8254R
Pin Number
37-PinTerminal
Block Number
Primary
Function
Alternate
Function
Signal Name
1
1
TTL Input 0
Pulse generator
trigger input
Trigger Change
Detector,
General-purpose
input
2
3
C
Common-mode
signal of the
NI 8254R main
power
—
3
4
4
5
TTL Output 0
TTL Output 1
Watchdog timer
output
General-purpose
output
Pulse generator
output
General-purpose
output
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Chapter 3
Signal Connections
Table 3-3. Signal Connections (Continued)
44-Pin D-SUB
on NI 8254R
Pin Number
37-PinTerminal
Block Number
Primary
Function
Alternate
Function
Signal Name
5
6
C
Common-mode
signal of the
NI 8254R main
power
—
6
7
8
7
8
6
TTL Output 2
TTL Output 3
C
Pulse generator
output
General-purpose
output
Pulse generator
output
General-purpose
output
Common-mode
signal of the
NI 8254R main
power
—
9
NC
TRIG 2*/TTL
Output 8
Pulse generator
output
General-purpose
output
10
11
17
Viso
Isolated power
—
NC
TRIG 0*/ISO
Input 12
Pulse generator
trigger input
Trigger Change
Detector,
General-purpose
input
12
13
14
19
35
34
ISO Output 0
ISO Output 1
Ciso
General-purpose
output
—
—
—
General-purpose
output
Isolated
common-mode
signal
15
9
ISO Input 0
Input port,
Data(0)
—
© National Instruments Corporation
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NI PCI-8254R User Manual
Chapter 3
Signal Connections
Table 3-3. Signal Connections (Continued)
44-Pin D-SUB
on NI 8254R
Pin Number
37-PinTerminal
Block Number
Primary
Function
Alternate
Function
Signal Name
16
2
TTL Input 1
Pulse generator
trigger input
Trigger Change
Detector,
General-purpose
input
17
3
C
Common-mode
signal of the
NI 8254R main
power
—
18
19
20
20
21
22
TTL Output 4
TTL Output 5
C
Pulse generator
output
General-purpose
output
General-purpose
output
—
Common-mode
signal of the
NI 8254R main
power
—
21
22
23
23
24
22
TTL Output 6
TTL Output 7
C
General-purpose
output
—
—
—
General-purpose
output
Common-mode
signal of the
NI 8254R main
power
24
NC
TRIG 1*/TTL
Output 9
Pulse generator
output
General-purpose
output
25
26
33
34
Viso
Ciso
Isolated power
—
—
Isolated
common-mode
signal
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Chapter 3
Signal Connections
Table 3-3. Signal Connections (Continued)
44-Pin D-SUB
on NI 8254R
Pin Number
37-PinTerminal
Block Number
Primary
Function
Alternate
Function
Signal Name
27
28
29
36
ISO Output 2
General-purpose
output
—
—
—
37
12
ISO Output 3
Ciso
General-purpose
output
Isolated
common-mode
signal
30
31
32
33
10
11
13
16
ISO Input 1
ISO Input 2
ISO Input 3
Ciso
Input port,
Data(1)
—
—
—
—
Input port,
Data(2)
Input port,
Data(3)
Isolated
common-mode
signal
34
35
36
14
15
28
ISO Input 4
ISO Input 5
Ciso
Input port,
Data(4)
—
Input port latch,
Data(5)
Pulse generator
trigger input
Isolated
—
common-mode
signal
37
38
39
25
26
28
ISO Input 6
ISO Input 7
Ciso
Quadrature
encoder Phase A input
General-purpose
Quadrature
encoder Phase B input
General-purpose
Isolated
—
common-mode
signal
© National Instruments Corporation
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Chapter 3
Signal Connections
Table 3-3. Signal Connections (Continued)
44-Pin D-SUB
on NI 8254R
Pin Number
37-PinTerminal
Block Number
Primary
Function
Alternate
Function
Signal Name
40
27
ISO Input 8
Pulse generator
trigger input
Trigger Change
Detector,
General-purpose
input
41
29
ISO Input 9
General-purpose Trigger Change
input
Detector,
General-purpose
input
42
43
32
30
Ciso
Isolated
common-mode
signal
—
ISO Input 10
General-purpose Trigger Change
input
Detector,
General-purpose
input
44
31
ISO Input 11
User shutdown
General-purpose
input
* TRIG 0, TRIG 1, and TRIG 2 are not available on the 37-pin terminal block or the signal accessory. If you need access to
these signals, you can get them directly from the 44-pin D-SUB connector.
Cabling
IEEE 1394 Camera Cables
You can connect cameras to the NI 8254R using standard IEEE 1394
cables. IEEE 1394 cables provide both a data path and power to your
camera.
I/O Terminal Block
National Instruments provides an I/O terminal block with the NI 8254R,
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 8254R.
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Chapter 3
Signal Connections
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, the
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.
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 8254R.
Isolated Outputs Power Connector
Figure 3-3 illustrates the isolated outputs power connector on the
NI 8254R.
V C
Figure 3-3. NI 8254R Isolated Power Connector
The isolated outputs power connector on the NI 8254R accommodates one
power supply. The V terminal provides the isolated output circuitry (5 to
30 VDC) for the NI 8254R. The C terminal provides the common-mode
signal for the NI 8254R, as shown in Table.
Table 3-4. Power Connector Terminals
Terminal
Description
V
C
Isolated power (5 to 30 VDC)
Isolated common-mode signal
© National Instruments Corporation
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NI PCI-8254R User Manual
A
Technical Support and
Professional Services
Visit the following sections of the National Instruments Web site at
ni.comfor technical support and professional services:
•
Support—Online technical support resources at ni.com/support
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/servicesor contact your local office at
ni.com/contact.
•
•
•
Training and Certification—Visit ni.com/trainingfor
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 ni.com/alliance.
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.
© National Instruments Corporation
A-1
NI PCI-8254R User Manual
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.comand 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/niglobalto access the branch
office Web sites, which provide up-to-date contact information, support
phone numbers, email addresses, and current events.
NI PCI-8254R User Manual
A-2
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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.
Digital camera.
DCAM
development machine
Machine used to develop an application. A development machine usually
has and ADE installed on it.
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.
© National Instruments Corporation
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NI PCI-8254R User Manual
Glossary
FireWire
FPGA
A high-speed serial interface invented by Apple Computer in 1989, also
known as IEEE 1394 or iLink.
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 the computer is still on.
I
IEEE
Institute of Electrical and Electronics Engineers. A standard-setting body
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.
NI PCI-8254R User Manual
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Glossary
PLC
Programmable Logic Controller. An industrial computer used for factory
automation, process control, and manufacturing systems.
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
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NI PCI-8254R User Manual
Index
A
acquisition window control, 1-4
general-purpose I/O, 2-9
general-purpose inputs, 2-10
C
cabling, 3-8
calibration certificate (NI resources), A-2
connector functions, 3-2
connectors, 3-2
help, technical support, A-1
2-position isolated output power, 3-2
I
I/O for fault conditions, 2-10
I/O for normal operation, 2-4
I/O terminal block, 3-8
IEEE 1394, 1-3
conventions used in the manual, v
D
camera cables, 3-8
IEEE 1394a
Declaration of Conformity (NI resources), A-1
diagnostic tools (NI resources), A-1
digital I/O
connector, 3-3
instrument drivers (NI resources), A-1
isolated inputs, 2-3
list of, 2-4
connection considerations, 2-12
overview, 2-1
documentation
isolated outputs, 2-3
list of, 2-4
NI resources, A-1
power connector, 3-9
drivers (NI resources), A-1
E
examples (NI resources), A-1
L
F
LabVIEW FPGA Module, 2-1
LabVIEW, Vision Builder AI, 1-2
latch, 2-9
FireWire, 1-3
FPGA, 2-1
© National Instruments Corporation
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NI PCI-8254R User Manual
Index
N
services, A-1
NI 1427
software programming choices
Inspection, 1-2
power connector terminals, 3-9
power requirements, 3-9
product selection port, 2-8
programming examples (NI resources), A-1
protecting inductive loads, 2-14
NI Vision Development Module, 1-2
NI 8254R
acquisition window control, 1-4
cabling, 3-8
connection considerations, 2-12
connector functions, 3-2
connectors, 3-2
pulse modes, 2-6
pulse width, 2-7
digital I/O, 2-1
functional overview, 1-3
general-purpose I/O, 2-9
I/O for fault conditions, 2-10
I/O for normal operation, 2-4
IEEE 1394, 1-3
quadrature encoder, 2-8
isolated inputs, 2-3
isolated outputs, 2-3
LabVIEW FPGA Module, 2-1
power requirements, 3-9
product selection port, 2-8
quadrature encoder, 2-8
reconfigurable I/O, 2-1
signal connections, 3-1
software overview, 1-1
start conditions, 1-4
timed pulse output, 2-5
TTL outputs, 2-2
shutdown, 2-11
software
overview, 1-1
software programming choices
NI Vision Builder for Automated
Inspection, 1-2
NI Vision Development Module, 1-2
start conditions, 1-4
support, technical, A-1
NI 8255R
NI Vision Terminal Block and
Prototyping Accessory, 3-9
NI support and services, A-1
NI Vision Assistant, 1-2
NI PCI-8254R User Manual
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Index
T
technical support, A-1
timed pulse output
watchdog timer, 2-11
Web resources, A-1
wiring
initiating, 2-5
overview, 2-5
isolated input to sourcing output device,
2-12
isolated output to external load, 2-13
training and certification (NI resources), A-1
transmission line effects, 2-15
trigger change detectors, 2-8
trigger inputs, 2-5
trigger polarity, 2-7
troubleshooting (NI resources), A-1
TTL inputs, 2-2
list of, 2-3
TTL outputs, 2-2
list of, 2-3
© National Instruments Corporation
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NI PCI-8254R User Manual
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