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National Instruments Corporate Headquarters
6504 Bridge Point Parkway Austin, Texas 78730-5039 USA Tel: 512 794 0100
Important Information
Warranty
The PCI-6110E/6111E boards are warranted against defects in materials and workmanship 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 workm anship, f or a period of 90 days fr om date of ship ment, as evid enced
by receipts or other documentation. National Instruments will, at its option, repair or replace software media that do
not execute programming instructions 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 p arts whic h are co vered by w arran ty.
National Instruments believes that the information in this manual is accurate. The document has been carefully
reviewed for technical accuracy. In the event that technical or typographical errors exist, National Instruments reserves
the right to make changes to subsequent editions of this document without prior notice to holders of this edition. The
reader should consult National Instruments if errors are suspected. In no event shall National Instrum ents be liable for
any damages arising out of or related to this document or the information contained in it.
XCEPT AS SPECIFIED HEREIN
E
SPECIFICALLY DISCLAIMS ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
USTOMER’S RIGHT TO RECOVER DAMAGES CAUSED BY FAULT OR NEGLIGENCE ON THE PART OF NATIONAL
C
NSTRUMENTS SHALL BE LIMITED TO THE AMOUNT THERETOFORE PAID BY THE CUSTOMER
I
WILL NOT BE LIABLE FOR DAMAGES RESULTING FROM LOSS OF DATA, PROFITS, USE OF PRODUCTS, OR INCIDENTAL OR
CONSEQUENTIAL DAMAGES, EVEN IF ADVISED OF THE POSSIBILITY THEREOF
Instruments will apply regardless of the form of action, whether in contract or tort, including negligence. Any action
against National Instruments must be brought within one year after the cause of action accrues. National Instruments
shall not be liable for any delay in performance due to causes beyond its reasonable control. The warranty provided
herein does not cover damages, defects, malfunctions, or service failures caused by owner’s failure to follow the
National Instruments installation, operation, or maintenance instructions; owner’s modification of the product;
owner’s abuse, misuse, or negligent acts; and power failure or surges, fire, flood, accident, actions of third parties,
or other events outside reasonable control.
ATIONAL INSTRUMENTS MAKES NO WARRANTIES, EXPRESS OR IMPLIED, AND
, N
.
ATIONAL INSTRUMENTS
. N
. This limitation of the liability of National
Copyright
Under the copyright laws, this publ ication may not be r eproduced or tr ansmitted in any form, electron ic or mechanical,
including photocopying, recording, storing in an information retrieval system, or translating, in whole or in part,
without the prior written consent of National Instruments Corporation.
Trademarks
ComponentWorks™, CVI™, DAQ-STC™, LabVIEW™, Measure™, MITE™, NI-DAQ™, NI-PGIA™, RTSI™,
SCXI™, and VirtualBench™ are trademarks of National Instruments Corporation.
Product and company names listed are trademarks or trade names of their respective companies.
WARNING REGARDING MEDICAL AND CLINICAL USE OF NATIONAL INSTRUMENTS PRODUCTS
National Instruments products are not designed with components and testing intended to ensure a level of reliability
suitable for use in treatment and diagnosis of humans. Applications of National Instruments products involving
medical or clinical treatment can create a potential for accidental injury caused by product failure, or by errors on the
part of the user or application designer. Any use or application of National Instruments products for or involving
medical or clinical treatment must be performed by properly trained and qualified medical personnel, and al l traditional
medical safeguards, equipment, and procedures that are appropriate in the particular situation to prevent serious injury
or death should always continue to be used when National Instruments products are being used. National Instruments
products are NOT intended to be a substitute for any form of esta blishe d process, proced ure, or equipm ent used to
monitor or safeguard human health and safety in medical or clinical treatment.
About This Manual
Organization of This Manual........................................................................................xi
Conventions Used in This Manual................................................................................xii
National Instruments Documentation.... .................................. .....................................xiii
Related Documentation........................................... ......................................................xiv
National Instruments CorporationixPCI-6110E/6111E User Manual
This manual describes the electrical and mechanical aspects of the
611XE family of boards and contains information concerning their
operation and programming.
The 611X E family of boards includes:
• PCI-6110E
• PCI-6111E
Your 611X E board is a high-performance multifunction analog, digital,
and timing I/O board for PCI bus computers. Supported functions
include analog input, analog output, digital I/O, and timingI/O.
Organization of This Manual
PCI-6110E/6111E User Manual
The
• Chapter1,
you need to get started, describes the optional software and optiona l
equipment, and explains how to unpack your 611X E board.
• Chapter2,
and configure your 611X E board.
• Chapter3,
hardware functions on your 611X E board.
• Chapter4,
output signal connections to your 611X E board via the board I/O
connector.
National Instruments CorporationxiPCI-6110E/6111E User Manual
About This Manual
• AppendixC,
asked questions and their answers relating to usage and special
features of your 611X E board.
• AppendixD,
use to request help from National Instruments or to comment on
ourproducts.
•The
•The
Glossary
used in this manual, including acronyms, abbreviations, defini tions
metric prefixes, mnemonics, and symbols.
Index
including the page where you can find the topic.
Common Questions
Customer Communication
contains an alphabetical list and description of terms
alphabetically lists topics covered in this manual,
, contains a list of commonly
, contains forms you can
Conventions Used in This Manual
The following conventions are used in this manual.
<> Angle brackets enclose the name of a key on the keyboard (for example,
<option>). Angle brackets containing numbers separated by an ellipsis
represent a range of values associated with a bit or signal name
(forexample, DIO<3..0>).
611X E This refers to either the PCI-6110E or PCI-6111E board.
This icon to the left of bold italiciz ed text de notes a n ote, which al erts
you to important information.
!
bold Bold text denotes the names of menus, menu items, parameters, dialog
bold italic Bold italic text denotes a note, caution, or warning.
italic
Macintosh Macintosh refers to all Macintosh OS computers with PCI bus, unless
PCI-6110E/6111E User Manualxii
This icon to the left of bold italiciz ed text de notes a ca ution, wh ich
advises you of precautions to take to avoid injury, data los s, or a
systemcrash.
boxes, dialog box buttons or options, icons, windows, Win dows 95 tabs,
or LEDs.
Italic text denotes emphasis, a cross reference, or an introduction to a
key concept. This font also denotes text from which you supply the
appropriate word or value, as in Windows 3.x.
monospaceText in this font denotes text or characters that you should literally enter
from the keyboard, sections of code, programming examples, and
syntax examples. This font also is used for the proper names of disk
drives, paths, directories, programs, subprograms, subroutines, device
names, functions, operations, variables, filenames, and extensions, and
for statements and comments taken from program code.
NI-DAQNI-DAQ refers to the NI-DAQ driver software for Macintosh or
PC compatible computers unless otherwise noted.
PCRefers to all PC AT series computers with PCI bus unless otherwise
noted.
SCXISCXI stands for Signal Conditioning eXentsions for Instrumentation
and is a National Instruments product line designed to perform
front-end signal conditioning for National instruments plug-in DAQ
boards.
National Instruments Documentation
PCI-6110E/6111E User Manual
The
set for your DAQ system. You could have any of several types of
documentation depending on the hardware and software in your system.
Use the documentation you have as follows:
Getting Started with SCXI
•
manual you should read. It gives an overview of the SCXI system
and contains the most commonly needed information for the
modules, chassis, and software.
•Your SCXI hardware user manuals—If you are using SCXI, read
these manuals next for detailed information about signal
connections and module configuration. They also explai n in greater
detail how the module works and contain application hints.
•Your DAQ hardware documentation—This documentation has
detailed information about the DAQ h ardware that plugs in to or is
connected to your computer. Use this documentation for hardware
installation and configuration instructions, specification
information about your DAQ hardware, and application hints.
•Software documentation—You may have both application software
and NI-DAQ software documentation. National Instruments
application software includes ComponentWorks, LabVIEW,
LabWindows/CVI, Measure, and VirtualBench. After you set up
your hardware system, use either your application software
National Instruments CorporationxiiiPCI-6110E/6111E User Manual
About This Manual
documentation or the NI-DAQ documentation to help you write
your application. If you have a large, complicated system, it is
worthwhile to look through the software documentation before you
configure your hardware.
• Accessory installation guides or manuals—If you are using
accessory products, read the terminal block and cable assembly
installation guides. They explain how to physically connect the
relevant pieces of the system. Consult these guides when you are
making your connections.
• SCXI chassis manuals—If you are using SCXI, read these manuals
for maintenance information on the chassis and installation
instructions.
Related Documentation
The following documents contain information you may find helpful:
• DAQ-STC Technical Reference Manual
• National Instruments Application Note 025,
Considerations for Analog Signals
• PCI Local Bus Specification Revision 2.0
Field Wiring and Noise
Customer Communication
National Instruments wants to receive your comments on our products
and manuals. We are interested in the applications you develop with our
products, and we want to help if you have problems with them. To make
it easy for you to contact us, this manual contains comment and
configuration forms for you to complete. These forms are in
This chapter describes your 611X E board, lists what you need to get
started, describes the optional software and optional equipment, and
explains how to unpack your 611X E board.
About the 611X E Boards
Thank you for buying a National Instruments PCI-6110E/6111E
board. Your 611X E board is a completely Plug and Play, multifunction
analog, digital, and timing I/O board for PCI bus computers. The
611XE board features a 12-bit ADC per channel with four or two
simultaneously sampling analog inputs, 16-bit DACs with voltage
outputs, eight lines of TTL-compatible digital I/O, and two 24-bit
counter/timers for timing I/O. Because the 611X E board has no DIP
switches, jumpers, or potentiometers, it is easily software-configured
and calibrated.
The 611X E board is a completely switchless and jumperless data
acquisition (DAQ) board for the PCI bus. This feature is made possible
by the National Instruments MITE bus interface chip that connects the
board to the PCI I/O bus. The MITE implements the PCI Local Bus
Specification so that the interrupts and base memory addresses are all
software configured.
1
The 611X E board uses the National Instruments DAQ-STC system
timing controller for time-related functions. The DAQ-STC consists
of three timing groups that control analog input, analog output, and
general-purpose counter/timer functions. These groups include a total
of seven 24-bit and three 16-bit counters and a maximum timing
resolution of 50 ns. The DAQ-STC makes possible such applications as
buffered pulse generation, equivalent time sampling, and seamlessly
changing the sampling rate.
Often with DAQ boards, you cannot easily synchronize several
measurement functions to a common trigger or timing event. The
611XE board has the Real-Time System Integration (RTSI) bus to
solve this problem. The RTSI bus consists of our RTSI bus interface
National Instruments Corporation1-1PCI-6110E/6111E User Manual
Chapter 1Introduction
and a ribbon cable to route timing and trigger signals between several
functions on as many as five DAQ boards in your computer.
Detailed specifications of the 611X E board are in Appendix A,
Specifications
.
What You Need to Get Started
To set up and use the 611X E board, you will need the following:
❑ Either the PCI-6110E or PCI-6111E board
PCI-6110E/6111E User Manual
❑
❑ One of the following software packages and documentation:
ComponentWorks
LabVIEW for Macintosh
LabVIEW for Windows
LabWindows/CVI for Windows
Measure
NI-DAQ for PC Compatibles
VirtualBench
❑ Your computer
Software Programming Choices
You have several options to choose from when programming your
National Instruments DAQ and SCXI hardware. You can use National
Instruments application software, NI-DAQ, or register-level
programming.
National Instruments Application Software
ComponentWorks contains tools for data acquisition and instrument
control built on NI-DAQ driver software. ComponentWorks provides
a higher-level programming interface for building virtual instruments
through standard OLE controls and DLLs. With Compon entWorks, you
can use all of the configuration tools, resource management utilities,
and interactive control utilities included with NI-DAQ.
LabVIEW features interactive graphics, a state-of-the-art user
interface, and a powerful graphical programming language. The
LabVIEW Data Acquisition VI Library, a series of VIs for using
LabVIEW with National Instruments DAQ hardware, is included with
LabVIEW. The LabVIEW Data Acquisition VI Library is functionally
equivalent to NI-DAQ software.
LabWindows/CVI features interactive graphics, state-of-the-art user
interface, and uses the ANSI standard C programming language. The
LabWindows/CVI Data Acquisition Library, a series of functions for
using LabWindows/CVI with National Instruments DAQ hardware, is
included with the NI-DAQ software kit. The LabWindows/CVI Data
Acquisition Library is functionally equivalent to the NI-DAQ softwar e.
VirtualBench features virtual instruments that combine DAQ pr oduct s,
software, and your computer to create a stand-alone instrument with the
added benefit of the processing, display, and storage cap abilities of
your computer. VirtualBench instruments load and save waveform data
to disk in the same forms that can be used in popular spreadsheet
programs and word processors.
Using ComponentWorks, LabVIEW, LabWindows/CVI, or
VirtualBench software will greatly reduce the development time
for your data acquisition and control application.
NI-DAQ Driver Software
The NI-DAQ driver software is included at no charge with all National
Instruments DAQ hardware. NI-DAQ is not packaged with SCXI or
accessory products, except for the SCXI-1200. NI-DAQ has an
extensive library of functions that you can call from your application
programming environment. These functions include routi nes for analog
input (A/D conversion), buffered data acquisition (high-speed A/D
conversion), analog output (D/A conversion), waveform generation
(timed D/A conversion), digital I/O, counter/timer operations, SCXI,
RTSI, self-calibration, messaging, and acquiring data to extended
memory.
NI-DAQ has both high-level DAQ I/O functions for maximum ease of
use and low-level DAQ I/O functions for maximum flexibility and
performance. Examples of high-level functions are streaming data to
disk or acquiring a certain number of data points. An example of a
low-level function is writing directly to registers on the DAQ device.
NI-DAQ does not sacrifice the performance of National Instruments
DAQ devices because it lets multiple devices operate at their peak.
National Instruments Corporation1-3PCI-6110E/6111E User Manual
Chapter 1Introduction
NI-DAQ also internally addresses many of the complex issues between
the computer and the DAQ hardware such as programming interrupts
and DMA controllers. NI-DAQ maintains a consistent software
interface among its different versions so that you can change platfor ms
with minimal modifications to your code. Whether you are using
conventional programming languages or National Instruments
application software, your application uses the NI-DAQ driver
software, as illustrated in Figure 1-1.
Figure 1-1. The Relationship between the Programming Environment,
Register-Level Programming
The final option for programming any National Instruments DAQ
hardware is to write register-level software. Writing register-level
programming software can be very time-consuming and inefficient,
and is not recommended for most users.
Conventional
Programming
Environment
DAQ or
SCXI Hardware
NI-DAQ, and Your Hardware
ComponentWorks,
LabVIEW,
LabWindows/CVI,
or VirtualBench
NI-DAQ
Driver Software
Personal Computer
or Workstation
Even if you are an experienced register-level programmer, using
NI-DAQ or application software to program your National Instruments
DAQ hardware is easier than, and as flexible as, register-level
programming, and can save weeks of development time.
National Instruments offers a variety of produ cts to use with the 611XE
board, including cables, connector blocks, and other accessories, as
follows:
•Cables and cable assemblies
•Connector blocks, shielded and unshielded 50- and 68-pin screw
terminals
•RTSI bus cables
•Low channel-count signal conditioning modules, boards, and
accessories, including conditioning for strain gauges, RTDs,
and relays
For more specific information about these products, refer to your
National Instruments catalogue or call the office nearest you.
Custom Cabling
National Instruments offers cables and accessories for you to prototype
your application or to use if you frequently change board
interconnections.
Chapter 1Introduction
If you want to develop your own cable, however, the following
guidelines may be useful:
•For the analog input signals, shielded twisted-pair wires for each
analog input pair yield the best results, assuming that you use
differential inputs. Tie the shield for each signal pair to the ground
reference at the source.
•Route the analog lines separately from the digital lines.
•When using a cable shield, use separate shields for the analog and
digital halves of the cable. Failure to do so results in noise coupling
into the analog signals from transient digital signals.
Mating connectors and a backshell kit for making custom 68-pin cables
are available from National Instruments.
National Instruments Corporation1-5PCI-6110E/6111E User Manual
Chapter 1Introduction
Unpacking
The following list gives recommended part numbers for connectors that
mate to the I/O connector on the 611X E board:
•Honda 68-position, solder cup, female connector
(part number PCS-E68FS)
•Honda backshell (part number PCS-E68LKPA)
The 611X E board is shipped in an antistatic package to prevent
electrostatic damage to the board. Electrostatic discharge can damage
several components on the board. To avoid such damage in handling
the board, take the following precautions:
•Ground yourself via a grounding strap or by holding a grounded
object.
•Touch the antistatic package to a metal part of your computer
chassis before removing the board from the package.
•Remove the board from the package and inspect the board for
loose components or any other sign of damage. Notify National
Instruments if the board appears damaged in any way. Do
install a damaged board into your computer.
This chapter explains how to install and configure your 611X E board.
Software Installation
Install your software before you install the 611X E board. Refer to the
appropriate release notes indicated below for specific instructions on
the software installation sequence.
If you are using LabVIEW, LabWindows/CVI, or other National
Instruments application software packages, refer to the appropriate
release notes. After you have installed your application software, refer
to your NI-DAQ release notes and follow the instructions given there
for your operating system and application software package.
If you are using NI-DAQ, refer to your NI-DAQ release notes. Find
theinstallation section for your operating system and follow the
instructions given there.
Hardware Installation
2
You can install the 611X E board in any available expansion slot in your
computer. However, to achieve best noise performance, leave as much
room as possible between the 611X E board and other boards and
hardware. The following are general installation instructions, but
consult your computer user manual or technical reference manual for
specific instructions and warnings.
1. Write down the 611X E board serial number in the
PCI-6110E/6111E Hardware and Software Configuration Form
AppendixD,
2. Turn off and unplug your computer.
3. Remove the top cover or access port to the I/O channel.
4. Remove the expansion slot cover on the back panel of the
computer.
National Instruments Corporation2-1PCI-6110E/6111E User Manual
Customer Communication
, of this manual.
in
Chapter 2Installation and Configuration
5.Insert the 611X E board into a 5 V PCI slot. Gently rock the board
to ease it into place. It may be a tight fit, but
into place.
6.If required, screw the mounting bracket of the 611X E board to the
back panel rail of the computer.
7.Replace the cover.
8.Plug in and turn on your computer.
The 611X E board is installed. You are now ready to configure your
software. Refer to your software documentation for configuration
instructions.
Board Configuration
Due to the National Instruments standard architecture for data
acquisition and the PCI bus specification, the 611X E board
is completely software configurable. You must perform two types
of configuration on the 611X E board—bus-related and data
acquisition-related configuration.
The 611X E board is fully compatible with the industry standard
PCI Local Bus Specification Revision 2.0
automatically perform all bus-related configurations and requires no
user interaction. Bus-related configuration includes setting the board
base memory address and interrupt channel.
do not force
. This allows the PCI system to
the board
Data acquisition-related configuration includes such settings as analog
input coupling and range, and others. You can modify these settings
using NI-DAQ or application level software, such as ComponentWorks,
LabVIEW, LabWindows/CVI, and VirtualBench.
National Instruments Corporation3-1PCI-6110E/6111E User Manual
Chapter 3Hardware Overview
Figure 3-2 shows a block diagram for the PCI-6111E board.
CH0+
AI CH0
Mux
CH0-
CH1+
AI CH1
Mux
CH1-
Calibration
Mux
Trigger Level
Trigger
I/O Connector
DACs
PFI / Trigger
Timing
Digital I/O (8)
DAC0
DAC1
Analog Input
+
CH0
Amplifier
–
+
CH1
Amplifier
–
2
4
Analog
Trigger
Circuitry
Calibration
DACs
CH0
12-Bit ADC
CH1
12-Bit ADC
DAC
FIFO
CH0
Trigger
Counter/
Timing I/O
Digital I/O
12
12
Data (16)
Latch
CH1
Data (16)
Latch
AI Control
Analog Input
Timing/Control
DAQ - STC
Analog Output
Timing/Control
AO Control
Data (32)
DMA/IRQ
Bus
Interface
RTSI Bus
Interface
ADC
FIFO
IRQ
DMA
RTSI Bus
Figure 3-2. PCI-6111E Block Diagram
Data (32)
Analog
Input
Control
DAQ-STC
Bus
Interface
Analog
Output
Control
Generic
Bus
Interface
EEPROM
EEPROM
Control
FPGA
Mini
MITE
Interface
DMA
Interface
I/O
Bus
Interface
PCI
Bus
Control
Address/Data
PCI Bus
The analog input section for the 611X E board is software configurable.
You can select different analog input configurations through
application software. The following sections describe in detail each of
the analog input categories.
Input Mode
The 611X E board supports only differential inputs (DIFF). The DIFF
input configuration provides up to four channels on the PCI-6110E
board and up to two channels on the PCI-6111E board.
A channel configured in DIFF mode uses two analog channel input lines.
One line connects to the positive input of the board programmable gain
instrumentation amplifier (PGIA), and the other connects to the negative
input of the PGIA. For more information about DIFF input
The 611X E board has bipolar inputs only. Bipolar input m eans that the
input voltage range is between –V
a bipolar input range of 20V (±10 V).
You can program range settings on a per channel basis so that you can
configure each input channel uniquely.
The software-programmable gain on these boards increases their
overall flexibility by matching the input signal ranges to those that the
ADC can accommodate. They have gains of 0.2, 0.5, 1, 2, 5, 10, 20, and
50, and are suited for a wide variety of signal levels. With the proper
gain setting, you can use the full resolution of the ADC to measure the
input signal. Table3-1 shows the overall input range and precision
according to the gain used.
Table 3-1.
Range
Configuration
Analog Input Signal Connections
, which contains diagrams showing the
and + V
ref
/2
Actual Range and Measurement Precision
GainActual Input Range
/2. These boards have
ref
1
section in
Precision
2
–10 to +10 V0.2
0.5
1.0
2.0
5.0
10.0
20.0
50.0
1
Warning:
user-installed voltage divider reduces the voltage to within the input range of the DAQ
device. Input voltages greater than 42 V can damage the 611X E, any device connected to
it, and the host computer. Overvoltage can also cause an electric shock hazard for the
operator. National Instruments is NOT liable for damage or injury resulting from such
misuse.
2
The value of 1 LSB of the 12-bit ADC; that is, the voltage increment corresponding to a
National Instruments Corporation3-3PCI-6110E/6111E User Manual
The 611X E is not designed for input voltages greater than 42 V, even if a
See Appendix A,
Specifications
–50 to +50 V
–20 to +20 V
–10 to +10 V
–5 to +5 V
–2 to +2 V
–1 to +1V
–500 to +500 mV
–200 to +200 mV
, for absolute maximum ratings.
24.41 mV
9.77 mV
4.88 mV
2.44 mV
976.56 µV
488.28 µV
244.14 µV
97.66 µV
Chapter 3Hardware Overview
Input Coupling
Dither
Considerations for Selecting Input Ranges
The range you select depends on the expected range of the incoming
signal. A large input range can accommodate a large signal variation
but reduces the voltage resolution. Choosing a smaller input range
improves the voltage resolution but may result in the input signal going
out of range. For best results, match the input range as closely as
possible to the expected range of the input signal.
You can configure the 611X E board for either AC or DC input coupling
on a per channel basis. Use AC coupling when your AC signal contains
a large DC component. If you enable AC coupling, you remove the
large DC offset for the input amplifier and amplify only the AC
component. This makes effective use of the ADC dynamic range.
Dither adds approximately 0.5 LSBrms of white Gaussian noise to
the signal to be converted by the ADC. This addition is useful for
applications involving averaging to increase the resolution of the
611XE board, as in calibration or spectral analysis. In such
applications, noise modulation is decreased and differential linearity is
improved by the addition of the dither. When taking DC measurements,
such as when checking the board calibration, you should average about
1,000 points to take a single reading. This process removes the effects
of quantization and reduces measurement noise, resulting in improved
resolution.
Figure 3-3 illustrates the effect of dither on signal acquisition.
Figure 3-3a shows a small (±4 LSB) sine wave acquired without dither.
The ADC quantization is clearly visible. Figure 3-3b shows what
happens when 50 such acquisitions are averaged together; quantization
is still plainly visible. In Figure 3-3c, the sine wave is acquired with
dither. There is a considerable amount of visible noise. But averaging
about 50 such acquisitions, as shown in Figure 3-3d, eliminates both the
added noise and the effects of quantization. Dither has the effect of
forcing quantization noise to become a zero-mean random variable
rather than a deterministic function of the input signal.
You cannot disable dither on the 611X E board. This is because the
ADC resolution is so fine that the ADC and the PGIA inherently
produce almost 0.5 LSBrms of noise. This is equivalent to having a
dither circuit that is always enabled.
LSBs
LSBs
6.0
6.0
4.0
4.0
2.0
2.0
0.0
0.0
-2.0
-2.0
-4.0
-4.0
-6.0
-6.0
1002003004000500
1002003004000500
a. Dither disabled; no averagingb. Dither disabled; average of 50 acquisitions
LSBs
LSBs
6.0
6.0
4.0
4.0
2.0
2.0
0.0
0.0
-2.0
-2.0
-4.0
-4.0
-6.0
-6.0
1002003004000500
1002003004000500
c. Dither enabled; no averagingd. Dither enabled; average of 50 acquisitions
LSBs
LSBs
6.0
6.0
4.0
4.0
2.0
2.0
0.0
0.0
-2.0
-2.0
-4.0
-4.0
-6.0
-6.0
LSBs
LSBs
6.0
6.0
4.0
4.0
2.0
2.0
0.0
0.0
-2.0
-2.0
-4.0
-4.0
-6.0
-6.0
1002003004000500
1002003004000500
1002003004000500
1002003004000500
Figure 3-3. Effects of Dither on Signal Acquisition
Analog Output
The 611X E boa r d supplies two channels of analog output voltage at the
I/O connector. The range is fixed at bipolar ±10 V.
National Instruments Corporation3-5PCI-6110E/6111E User Manual
Chapter 3Hardware Overview
Analog Trigger
Note:The PFI0/TRIG1 pin is an analog input when configured as an analog
trigger. Therefore, it is susceptible to crosstalk from adjacent pins, which
can result in false triggering when the pin is left unconnected. To avoid
false triggering, make sure this pin is connected to a low-impedance signal
source (less than 1 kΩ source impedance) if you plan to enable this input
via software.
In addition to supporting internal software triggering and external
digital triggering to initiate a data acquisition sequence, these boards
also support analog triggering. You can configure the analog trigger
circuitry to accept either a direct analog input from the PFI0/TRIG1 pin
on the I/O connector or a postgain signal from the output of the PGIA
on any of the channels, as shown in Figures 3-4 and 3-5. The
trigger-level range for the direct analog channel is ±10 V in 78 mV steps
for the 611X E board. The range for the post-PGIA trigger selection is
simply the full-scale range of the selected channel, and the resolution is
that range divided by 256.
Figure 3-5. Analog Trigger Block Diagram for the PCI-6111E
Five analog triggering modes are available, as shown in Figures 3-6
through 3-10. You can set lowValue and highValue independently in
software.
In below-low-level analog triggering mode, the trigger is generated
when the signal value is less than lowValue, as shown in Figure 3-6.
HighValue is unused.
lowValue
Trigger
Figure 3-6. Below-Low-Level Analog Triggering Mode
National Instruments Corporation3-7PCI-6110E/6111E User Manual
Chapter 3Hardware Overview
In above-high-level analog triggering mode, the trigger is generated
when the signal value is greater than highValue, as shown in Figure 3-7.
LowValue is unused.
highValue
Trigger
Figure 3-7. Above-High-Level Analog Triggering Mode
In inside-region analog triggering mode, the trigger is generated when
the signal value is between the lowValue and the highValue, as shown
in Figure 3-8.
In high-hysteresis analog triggering mode, the trigger is generated when
the signal value is greater than highValue, with the hysteresis specified
by lowValue, as shown in Figure 3-9.
highValue
lowValue
Trigger
Figure 3-9. High-Hysteresis Analog Triggering Mode
In low-hysteresis analog triggering mode, the trigger is generated when
the signal value is less than lowValue, with the hysteresis specified by
highValue, as shown in Figure 3-10.
highValue
lowValue
Trigger
Figure 3-10. Low-Hysteresis Analog Triggering Mode
The analog trigger circuit generates an internal digital trigger based on
the analog input signal and the user-defined trigger levels. This digital
trigger can be used by any of the timing sections of the DAQ-STC,
including the analog input, analog output, and general-purpose
counter/timer sections. For example, the analog input section can be
configured to acquire n scans after the analog input signal crosses a
specific threshold. As another example, the analog output section can
be configured to update its outputs whenever the analog input signal
crosses a specific threshold.
National Instruments Corporation3-9PCI-6110E/6111E User Manual
Chapter 3Hardware Overview
Digital I/O
The 611X E board contains eight lines of digital I/O for general-purpose
use. You can individually software-configure each line for either input
or output. At system startup and reset, the digital I/O ports are all high
impedance.
The hardware up/down control for general-purpose counters 0 and 1 are
connected onboard to DIO6 and DIO7, respectively. Thus, you can use
DIO6 and DIO7 to control the general-purpose counters. The up/down
control signals are input only and do not affect the operation of the DIO
lines.
The DAQ-STC provides a very flexible interface for connecting timing
signals to other boards or external circuitry. The 611X E board uses the
RTSI bus to interconnect timing signals between boards, and the
Programmable Function Input (PFI) pins on the I/O connector to
connect the board to external circuitry. These connections are designed
to enable the 611X E board to both control and be controlled by other
boards and circuits.
There are a total of 13 timing signals internal to the DAQ-STC that can
be controlled by an external source. These timing signals can also be
controlled by signals generated internally to the DAQ-STC, and these
selections are fully software configurable. For example, the signal
routing multiplexer for controlling the CONVERT* signal is shown in
Figure 3-11.
National Instruments Corporation3-11PCI-6110E/6111E User Manual
CONVERT* Signal Routing
Chapter 3Hardware Overview
This figure shows that CONVERT* can be generated from a number of
sources, including the external signals RTSI<0..6> and PFI<0..9> and
the internal signals Sample Interval Counter TC and GPCTR0_OUT.
Many of these timing signals are also available as outputs on the RTSI
pins, as indicated in the
on the PFI pins, as indicated in Chapter4,
Programmable Function Inputs
The 10PFIs are connected to the signal routing multiplexer for each
timing signal, and software can select one of the PFIs as the external
source for a given timing signal. It is important to note that any of the
PFIs can be used as an input by any of the timing signals and that
multiple timing signals can use the same PFI simultaneously. This
flexible routing scheme reduces the need to change physical
connections to the I/O connector for different applications. You can
also individually enable each of the PFI pins to output a specific internal
timing signal. For example, if you need the UPDATE* signal as an
output on the I/O connector, software can turn on the output driver for
the PFI5/UPDATE* pin.
RTSI Triggers
section later in this chapter, and
Signal Connections
.
Board and RTSI Clocks
Many functions performed by the 611X E board require afrequency
timebase to generate the necessary timing signals for controlling A/D
conversions, DAC updates, or general-purpose signals at the I/O
connector.
The 611X E board can use either its internal 20 MHz timebase or a
timebase received over the RTSI bus. In addition, if you configure the
board to use the internal timebase, you can also program the board to
drive its internal timebase over the RTSI bus to another board that is
programmed to receive this timebase signal. This clock source, whether
local or from the RTSI bus, is used directly by the board as the primary
frequency source. The default configuration at startup is to use the
internal timebase without driving the RTSI bus timebase signal. This
timebase is software selectable.
The seven RTSI trigger lines on the RTSI bus provide a very flexible
interconnection scheme for the 611X E board sharing the RTSI bus.
These bidirectional lines can drive any of eight timing signals onto the
RTSI bus and can receive any of these timing signals. This signal
connection scheme is shown in Figure3-12.
National Instruments Corporation3-13PCI-6110E/6111E User Manual
Timing Connections
, for a description of the signals shown in Figure3-12.
RTSI Bus Signal Connection
section of Chapter4,
Signal
Chapter
Signal Connections
This chapter describes how to make input and output si gnal connections
to your 611X E board via the board I/O connector.
The I/O connector for the 611X E board has 68 pins that you can connect
to 68-pin accessories with the SH6868EP shielded cable.
I/O Connector
Figure 4-1 shows the pin assignments for the 68-pin I/O connector on
the 611X E board. A signal description follows the connector pinouts.
!
Caution:
Connections that exceed any of the maximum ratings of input or output
signals on the 611X E board can damage the 611X E board and the
computer. Maximum input ratings for each signal are given in the
Protection
any damages resulting from such signal connections.
National Instruments Corporation4-3PCI-6110E/6111E User Manual
Digital I/O signals—DIO6 and 7 can control the up/down
signal of general-purpose counters 0 and 1, respectively.
+5 V supply. The fuse is self-resetting.
when enabled. The low-to-high edge indicates when the
input signal can be removed from the input or switched to
another signal.
control to latch signals or trigger events on external devices.
Chapter 4Signal Connections
Table 4-1. Signal Descriptions for I/O Connector Pins (Continued)
Signal NameReferenceDirectionDescription
PFI0/TRIG1DGNDInput
Output
PFI1/TRIG2DGNDInput
Output
PFI2/CONVERT* DGNDInput
Output
PFI3/GPCTR1_SOURCE DGNDInput
Output
PFI0/Trigger 1—As an input, this is either one of the
Programmable Function Inputs (PFIs) or the source for the
hardware analog trigger. PFI signals are explained in the
Timing Connections section later in this chapter. The
hardware analog trigger is explained in the Analog Trigger
section in Chapter 3, Hardware Overview.
As an output, this is the TRIG1 signal. In posttrigger data
acquisition sequences, a low-to-high transition indicates the
initiation of the acquisition sequence. In pretrigger
applications, a low-to-high transition indicates the initiation
of the pretrigger conversions.
PFI1/Trigger 2—As an input, this is one of the PFIs.
As an output, this is the TRIG2 signal. In pretrigger
applications, a low-to-high transition indicates the initiation
of the posttrigger conversions. TRIG2 is not used in
posttrigger applications.
PFI2/Convert—As an input, this is one of the PFIs.
As an output, this is the CONVERT* signal. A high-to-low
edge on CONVERT* indicates that an A/D conversion is
occurring.
PFI3/Counter 1 Source—As an input, this is one of the
PFIs.
As an output, this is the GPCTR1_SOURCE signal. This
signal reflects the actual source connected to the
general-purpose counter 1.
PFI4/GPCTR1_GATEDGNDInput
Output
GPCTR1_OUTDGNDOutputCounter 1 Output—This output is from the general-purpose
PFI5/UPDATE*DGNDInput
Output
PCI-6110E/6111E User Manual4-4
PFI4/Counter 1 Gate—As an input, this is one of the PFIs.
As an output, this is the GPCTR1_GATE signal. This signal
reflects the actual gate signal connected to the
general-purpose counter 1.
counter 1 output.
PFI5/Update—As an input, this is one of the PFIs.
As an output, this is the UPDATE* signal. A high-to-low
edge on UPDATE* indicates that the analog output primary
group is being updated.
Table 4-1. Signal Descriptions for I/O Connector Pins (Continued)
Signal NameReferenceDirectionDescription
PFI6/WFTRIGDGNDInput
Output
PFI7/STARTSCANDGNDInput
Output
PFI8/GPCTR0_SOURCEDGNDInput
Output
PFI9/GPCTR0_GATEDGNDInput
Output
GPCTR0_OUTDGNDOutputCounter 0 Output—This output is from the general-purpose
PFI6/Waveform Trigger—As an input, this is one of the
PFIs.
As an output, this is the WFTRIG signal. In timed analog
output sequences, a low-to-high transition indicates the
initiation of the waveform generation.
PFI7/Start of Scan—As an input, this is one of the PFIs.
As an output, this is the STARTSCAN signal. This pin
pulses once at the start of each analog input scan in the
interval scan. A low-to-high transition indicates the start of
the scan.
PFI8/Counter 0 Source—As an input, this is one of the
PFIs.
As an output, this is the GPCTR0_SOURCE signal. This
signal reflects the actual source connected to the
general-purpose counter 0.
PFI9/Counter 0 Gate—As an input, this is one of the PFIs.
As an output, this is the GPCTR0_GATE signal. This signal
reflects the actual gate signal connected to the
general-purpose counter 0.
counter 0 output.
FREQ_OUTDGNDOutputFrequency Output—This output is from the frequency
National Instruments Corporation4-7PCI-6110E/6111E User Manual
Chapter 4Signal Connections
Analog Input Signal Connections
The analog input signals for the 611X E board are ACH<0..3>+ and
ACH<0..3>–. The ACH<0..3>+ signals are routed to the positive input
of the PGIA, and signals connected to ACH<0..3>– are routed to the
negative input of the PGIA.
Caution:Exceeding the differential and common-mode input ranges distorts your
!
input signals. Exceeding the maximum input voltage rating can damage
the 611X E board and the computer. National Instruments is
any damages resulting from such signal connections. The maximum input
voltage ratings are listed in the
Protection
With the different configurations, you can use the PGIA in different
ways. Figure 4-2 shows a diagram of your 611X E board PGIA.
V
in+
+
NOT
column of Table 4-2.
Instrumentation
Amplifier
liable for
V
in-
Figure 4-2.
The PGIA applies gain and common-mode voltage rejection and
presents high input impedance to the analog input signals connected to
the 611X E board. Signals are routed to the positive and negative inpu ts
of the PGIA. The PGIA converts two input signals to a signal that is the
difference between the two input signals multiplied by the gain setting
of the amplifier. The amplifier output voltage is referenced to the
ground for the board. The 611X E board A/D converter (ADC) measures
this output voltage when it performs A/D conversions.
When making signal connections, you must first determine whether the
signal sources are floating or ground-referenced. The following
sections describe these two types of signals.
Floating Signal Sources
A floating signal source is not connected in any way to the building
ground system but, rather, has an isolated ground-reference point. Some
examples of floating signal sources are outputs of transformers,
thermocouples, battery-powered devices, optical isolator outputs, and
isolation amplifiers. An instrument or device that has an isolated output
is a floating signal source. You must tie the ground reference of a
floating signal to the 611X E board analog input ground to establish a
local or onboard reference for the signal. Otherwise, the measured input
signal varies as the source floats out of the common-mode input range.
Ground-Referenced Signal Sources
A ground-referenced signal source is connected in some way to the
building system ground and is, therefore, already connected to a
common ground point with respect to the 611X E board, assuming that
the computer is plugged into the same power system. Nonisolated
outputs of instruments and devices that plug into the buildin g power
system fall into this category.
Chapter 4Signal Connections
The difference in ground potential between two instruments connected
to the same building power system is typically between 1 and 100 mV
but can be much higher if power distribution circuits are not properly
connected. If a grounded signal source is improperly measured, this
difference may appear as an error in the measurement. The connection
instructions for grounded signal sources are designed to eliminate this
ground potential difference from the measured signal.
Differential Measurements
The following sections discuss the use of differential (DIFF)
measurements and considerations for measuring both floating and
ground-referenced signal sources.
National Instruments Corporation4-9PCI-6110E/6111E User Manual
Chapter 4Signal Connections
Table 4-3 summarizes the recommended DIFF signal connections and
includes input examples for both types of signal sources.
Table 4-3.
Signal Source Types
DIFF Input
Examples and
Signal Source
Floating Signal Source
(Not Connected to Building Ground)
Input Examples• Ungrounded Thermocouples
• Signal conditioning with isolated
outputs
• Battery devices
Differential
(DIFF)
+
V
1
-
See text for information on bias resistors.
ACH0(+)
ACH0(-)
ACH0GND
Differential Connection Considerations
A differential connection is one in which the 611X E board analog input
signal has its own reference signal or signal return path. The 611X E
channels are always configured in DIFF input mode. The input signal is
tied to the positive input of the PGIA, and its reference signal, or return,
is tied to the negative input of the PGIA.
Grounded Signal Source
• Plug-in cards with nonisolated
outputs
+
-
+
V
1
-
ACH0(+)
ACH0(-)
ACH0GND
+
-
Each differential signal uses two inpu ts—one for the si gnal an d one for
its reference signal.
Differential signal connections reduce picked up noise and increase
common-mode noise rejection. Differential signal connections also
allow input signals to float within the common-mode limits of the
PGIA.
Differential Connections for Ground-Referenced
Signal Sources
Figure 4-3 shows how to connect a ground-referenced signal source to
a channel on the 611X E board.
Ground-
Referenced
Signal
Source
Common-
Mode
Noise and
Ground
Potential
+
V
s
-
+
V
cm
-
I/O Connector
ACH0+
ACH0-
ACH0GND
ACH0 Connections Shown
Figure 4-3.
Differential Input Connections for Ground-Referenced Signals
Instrumentation
Amplifier
+
PGIA
-
+
Measured
V
m
Voltage
-
With this type of connection, the PGIA rejects both the common-mode
noise in the signal and the ground potential difference between the
signal source and the 611X E board ground, shown as V
in Figure 4-3.
cm
Differential Connections for Nonreferenced or
Floating Signal Sources
Figure 4-4 shows how to connect a floating signal source to a channel
on the 611X E board.
National Instruments Corporation4-11PCI-6110E/6111E User Manual
Chapter 4Signal Connections
ACH0+
Floating
Signal
Source
+
V
S
-
Bias
Current
Return
Paths
Bias
Resistor
(see text)
I/O Connector
Instrumentation
Amplifier
1MΩ100pf
ACH0-
10nf
ACH0GND
ACH0 Connections Shown
+
PGIA
-
+
Measured
V
m
Voltage
-
Figure 4-4. Differential Input Connections for Nonreferenced Signals
Figure 4-4 shows a bias resistor connected between ACH0 – and the
floating signal source ground. If you do not use the resistor and the
source is truly floating, the source is not likely to remain within the
common-mode signal range of the PGIA, and the PGIA will saturate,
causing erroneous readings. You must reference the source to the
respective channel ground.
Common-Mode Signal Rejection Considerations
Figure 4-3 shows connections for signal sources that ar e already
referenced to some ground point with respect to the 611X E board. In
this case, the PGIA can reject any voltage caused by ground potential
differences between the signal source and the board. In addition, with
differential input connections, the PGIA can reject common-mode noise
pickup in the leads connecting the signal sources to the board. The
PGIA can reject common-mode signals as long as V
signals) are both within ±11 V of the channel ground, for gain ≥ 1. For
gain <1, the input signals, for ACHO +, can be within ±42 V of the
channel ground.
The analog output signals are DAC0OUT, DAC1OUT, and AOGND.
DAC0OUT is the voltage output signal for analog output channel 0.
DAC1OUT is the voltage output signal for analog output channel 1.
AOGND is the ground reference signal for the analog output channels.
Figure 4-5 shows how to make analog output connections to the
611X E board.
DAC0OUT
+
Load
VOUT 0
-
-
AOGND
Chapter 4Signal Connections
Channel 0
Load
VOUT 1
+
DAC1OUT
Figure 4-5.
Channel 1
Analog Output Channels
611X E Board
Analog Output Connections
Digital I/O Signal Connections
The digital I/O signals are DIO<0..7> and DGND. DIO<0..7> are the
signals making up the DIO port, and DGND is the ground reference
signal for the DIO port. You can program all lines individually to be
inputs or outputs.
National Instruments Corporation4-13PCI-6110E/6111E User Manual
Chapter 4Signal Connections
Caution:Exceeding the maximum input voltage ratings, which are listed in
!
Table 4-2, can damage the 611X E board and the computer. National
Instruments is
connections.
LED
liable for any damages resulting from such signal
NOT
Figure 4-6 shows signal connections for three typical digital I/O
applications.
+5 V
DIO<4..7>
+5 V
TTL Signal
DIO<0..3>
Switch
DGND
I/O Connector
611X E Board
Figure 4-6. Digital I/O Connections
Figure 4-6 shows DIO<0..3> configured for digital input and
DIO<4..7> configured for digital output. Digital input applications
include receiving TTL signals and sensing external device states such
as the switch state shown in Figure 4-6. Digital output applications
include sending TTL signals and driving external devices such as the
LED shown in Figure 4-6.
Two pins on the I/O connector supply +5 V from the computer power
supply via a self-resetting fuse. The fuse will reset automatically wit hin
a few seconds after the overcurrent condition is removed. These pins are
referenced to DGND and can be used to power external digital circuitry.
• Power rating +4.65 to +5.25 VDC at 1 A
Caution: Under no circumstances should you connect these +5 V power pins directly
!
to analog or digital ground or to any other voltage source on the 611X E
board or any other device. Doing so can damage the 61 1X E board a nd the
computer. National Instruments is
such a connection.
Timing Connections
Caution: Exceeding the maximum input voltage ratings, which are listed in
!
Table4-2, can damage the 611X E board and the computer. National
Instruments is
connections.
Chapter 4Signal Connections
liable for damages resulting from
NOT
liable for any damages resulting from such signal
NOT
All external control over the timing of the 611X E board isrouted
through the 10 programmable function inputs labeled PFI0 through
PFI9. These signals are explained in detail in the next section,
Programmable Function Input Connections
bidirectional; as outputs they are not programmable and reflect the state
of many DAQ, waveform generation, and general-purpose timing
signals. There are five other dedicated outputs for the remainder of the
timing signals. As inputs, the PFI signals are programmable and can
control any DAQ, waveform generation, and general-purpose timing
signals.
The DAQ signals are explained in the
later in this chapter. The waveform generation signals are explained in
Waveform Generation Timing Connections
the
chapter. The general-purpose timing signals are explained in the
National Instruments Corporation4-15PCI-6110E/6111E User Manual
. These PFIs are
DAQ Timing Connections
section later in this
section later in this
section
Chapter 4Signal Connections
All digital timing connections are referenced to DGND. This reference
is demonstrated in Figure 4-7, which shows how to connect an external
TRIG1 source and an external CONVERT* source to t wo 611X E board
PFI pins.
PFI0/TRIG1
PFI2/CONVERT*
TRIG1
Source
CONVERT*
Source
I/O Connector
Figure 4-7. Timing I/O Connections
Programmable Function Input Connections
There are a total of 13 internal timing signals that you can externally
control from the PFI pins. The source for each of these signals is
software-selectable from any of the PFIs when you want external
control. This flexible routing scheme reduces the need to change the
physical wiring to the board I/O connector for different applications
requiring alternative wiring.
You can individually enable each of the PFI pins to output a specific
internal timing signal. For example, if you need the CONVERT* signal
as an output on the I/O connector, software can turn on the output driver
for the PFI2/CONVERT* pin. Be careful not to drive a PFI signal
externally when it is configured as an output.
As an input, you can individually configure each PFI for edge or level
detection and for polarity selection, as well. You can use the polarity
selection for any of the 13 timing signals, but the edge or level detection
will depend upon the particular timing signal being controlled. The
detection requirements for each timing signal are listed within the
section that discusses that individual signal.
In edge-detection mode, the minimum pulse width required is 10 ns.
This applies for both rising-edge and falling-edge polarity settings.
There is no maximum pulse-width requirement in edge-detect mode.
In level-detection mode, there are no minimum or maximum
pulse-width requirements imposed by the PFIs themselves, but there
may be limits imposed by the particular timing signal being controlled.
These requirements are listed later in this chapter.
DAQ Timing Connections
The DAQ timing signals are SCANCLK, EXTSTROBE*, TRIG1,
TRIG2, STARTSCAN, CONVERT*, AIGATE, and SISOURCE.
Chapter 4Signal Connections
Posttriggered data acquisition allows you to view only data that is
acquired after a trigger event is received. A typical posttriggered DAQ
sequence is shown in Figure 4-8. Pretriggered data acquisition allows
you to view data that is acquired before the trigger of interest in addition
to data acquired after the trigger. Figure 4-9 shows a typical
pretriggered DAQ sequence. The description for each signal shown in
these figures is included later in this chapter.
National Instruments Corporation4-17PCI-6110E/6111E User Manual
Typical Posttriggered Acquisition
13042
Chapter 4Signal Connections
TRIG1
TRIG2
STARTSCAN
CONVERT*
Scan Counter
Don't Care
012310222
Figure 4-9. Typical Pretriggered Acquisition
SCANCLK Signal
SCANCLK is an output-only signal that generates a pulse with the
leading edge occurring approximately 50 to 100 ns after an A/D
conversion begins. The polarity of this output is software-selectable but
is typically configured so that a low-to-high leading edge can clock
external analog input multiplexers indicating when the input signal has
been sampled and can be removed. This signal has a 450 ns pulse width
and is software enabled. Figure 4-10
SCANCLK signal.
CONVERT*
SCANCLK
shows the timing for the
t
d
t
= 50 to 100 ns
d
t
= 450 ns
w
t
w
Figure 4-10. SCANCLK Signal Timing
EXTSTROBE* Signal
EXTSTROBE* is an output-only signal that generates either a single
pulse or a sequence of eight pulses in the hardware-strobe mode. An
external device can use this signal to latch signals or to trigger events.
In the single-pulse mode, software controls the level of the
EXTSTROBE* signal. A 10 µs and a 1.2 µs clock are available for
generating a sequence of eight pulses in the hardware-strobe mode.
Figure4-11 shows the timing for the hardware-strobe mode
EXTSTROBE* signal.
V
OH
V
OL
t
t
w
w
t
= 600 ns or 5 µs
w
Figure 4-11. EXTSTROBE* Signal Timing
TRIG1 Signal
Any PFI pin can externally input the TRIG1 signal, which is available
as an output on the PFI0/TRIG1 pin.
Refer to Figures4-8 and4-9 for the relationship of TRIG1 to the DAQ
sequence.
As an input, the TRIG1 signal is configured in t he edge-detection mode.
You can select any PFI pin as the source for TRIG1 and configure the
polarity selection for either rising or falling edge. The selected edge
ofthe TRIG1 signal starts the data acquisition sequence for both
posttriggered and pretriggered acquisitions. The 611X E supports
analog triggering on the PFI0/TRIG1 pin. See Chapter3,
Hardware Overview
, for more information on analog triggering.
As an output, the TRIG1 signal reflects the action that initiates a DAQ
sequence. This is true even if the acquisition is being externally
triggered by another PFI. The output is an active high pulse with a
pulsewidth of 25 to 50ns. This output is set to tri-state at startup.
National Instruments Corporation4-19PCI-6110E/6111E User Manual
Chapter 4Signal Connections
Figures 4-12 and 4-13 show the input and output timing requirements
for the TRIG1 signal.
t
w
Rising-edge
polarity
Falling-edge
polarity
t
= 10 ns minimum
w
Figure 4-12. TRIG1 Input Signal Timing
t
w
Figure 4-13. TRIG1 Output Signal Timing
The board also uses the TRIG1 signal to initiate pretriggered DAQ
operations. In most pretriggered applications, the TRIG1 signal is
generated by a software trigger. Refer to the TRIG2 signal description
for a complete description of the use of TRIG1 and TRIG2 in a
pretriggered DAQ operation.
TRIG2 Signal
Any PFI pin can externally input the TRIG2 signal, which is available
as an output on the PFI1/TRIG2 pin. Refer to Figure 4-9 for the
relationship of TRIG2 to the DAQ sequence.
As an input, the TRIG2 signal is configured in the edge-detection mode.
You can select any PFI pin as the source for TRIG2 and configure the
polarity selection for either rising or falling edge. The selected edge of
the TRIG2 signal initiates the posttriggered phase of a pretriggered
acquisition sequence. In pretriggered mode, the TRIG1 signal initiates
the data acquisition. The scan counter indicates the minimum number
of scans before TRIG2 can be recognized. After the scan counter
decrements to zero, it is loaded with the number of posttrigger scans to
acquire while the acquisition continues. The board ignores the TRIG2
signal if it is asserted prior to the scan counter decrementing to zero.
After the selected edge of TRIG2 is received, the board will acquire a
fixed number of scans and the acquisition will stop. This mode acquires
data both before and after receiving TRIG2.
As an output, the TRIG2 signal reflects the posttrigger in a pretriggered
acquisition sequence. This is true even if the acquisition is being
externally triggered by another PFI. The TRIG2 signal is not used in
posttriggered data acquisition. The output is an active high pulse with a
pulse width of 25 to 50 ns. This output is set to tri-state at startup.
Figures 4-14 and 4-15 show the input and output timing requirements
for the TRIG2 signal.
National Instruments Corporation4-21PCI-6110E/6111E User Manual
Chapter 4Signal Connections
STARTSCAN Signal
Any PFI pin can externally input the STARTSCAN signal, which is
available as an output on the PFI7/STARTSCAN pin. Refer to
Figures 4-8 and 4-9 for the relationship of STARTSCAN to the DAQ
sequence.
As an input, the STARTSCAN signal is configured in the
edge-detection mode. You can select any PFI pin as the source for
STARTSCAN and configure the polarity selection for either rising or
falling edge. The selected edge of the STARTSCAN signal initiates a
scan. The sample interval counter starts if you select internally
triggered CONVERT*.
As an output, the STARTSCAN signal reflects the actual start pulse that
initiates a scan. This is true even if the starts are being externally
triggered by another PFI. You have two output options. The first is an
active high pulse with a pulse width of 25 to 50 ns, which indicates the
start of the scan. The second action is an active high pulse that
terminates at the start of the last conversion in the scan, which indicates
a scan in progress. STARTSCAN will be deasserted t
conversion in the scan is initiated. This output is set to tri-state at
startup.
after the last
off
Figures 4-16 and 4-17 show the input and output timing requirements
for the STARTSCAN signal.
The CONVERT* pulses are masked off until the board generates the
STARTSCAN signal. If you are using internally generated conversions,
the first CONVERT* appears when the onboard sample interval counter
reaches zero. If you select an external CONVERT*, the first external
pulse after STARTSCAN generates a conversion. The STARTSCAN
pulses should be separated by at least one scan period.
A counter on the 611X E board internally generates the STARTSCAN
signal unless you select some external source. This counter is started by
the TRIG1 signal and is stopped either by software or by the sample
counter.
Scans generated by either an internal or external STARTSCAN signal
are inhibited unless they occur within a DAQ sequence. Scans occurring
within a DAQ sequence may be gated by either the hardware (AIGATE)
signal or software command register gate.
CONVERT* Signal
Any PFI pin can externally input the CONVERT* signal, which is
available as an output on the PFI2/CONVERT* pin.
National Instruments Corporation4-23PCI-6110E/6111E User Manual
Chapter 4Signal Connections
Refer to Figures 4-8 and 4-9 for the relationship of STARTSCAN to the
DAQ sequence.
As an input, the CONVERT* signal is configure d in the edge-det ection
mode. You can select any PFI pin as the source for CONVERT* and
configure the polarity selection for either rising or falling edge. The
selected edge of the CONVERT* signal initiates an A/D conversion.
As an output, the CONVERT* signal reflects the actual convert pulse
that is connected to the ADC. This is true even if the conversions are
being externally generated by another PFI. The o utput is a n active low
pulse with a pulse width of 50 to 100 ns. This output is set to tri-state at
startup.
Figures 4-18 and 4-19 show the input and output timing requirements
for the CONVERT* signal.
t
w
Rising-edge
polarity
Falling-edge
polarity
Figure 4-18. CONVERT* Input Signal Timing
Figure 4-19. CONVERT* Output Signal Timing
The ADC switches to hold mode within 20 ns of the selected edge. This
hold-mode delay time is a function of temperature and does not vary
from one conversion to the next.
The sample interval counter on the 611X E board normally generates the
CONVERT* signal unless you select some external source. The counter
is started by the STARTSCAN signal and continues to count down and
reload itself until the scan is finished. It then reloads itself in
preparation for the next STARTSCAN pulse.
A/D conversions generated by either an internal or external
CONVERT* signal are inhibited unless they occur within a DAQ
sequence. Scans occurring within a DAQ sequence may be gated by
either the hardware (AIGATE) signal or software command register
gate.
AIGATE Signal
Any PFI pin can externally input the AIGATE signal, which is not
available as an output on the I/O connector. The AIGATE signal can
mask off scans in a DAQ sequence. You can configure the PFI pin you
select as the source for the AIGATE signal in either the level-detection
or edge-detection mode. You can configure the polarity selection for the
PFI pin for either active high or active low.
In the level-detection mode if AIGATE is active, the STARTSCAN
signal is masked off and no scans can occur. In the edge-detection
mode, the first active edge disables the STARTSCAN signal, and the
second active edge enables STARTSCAN.
The AIGATE signal can neither stop a scan in progress nor continue a
previously gated-off scan; in other words, once a scan has started,
AIGATE does not gate off conversions until the beginning of the next
scan and, conversely, if conversions are being gated off, AIGATE does
not gate them back on until the beginning of the next scan.
SISOURCE Signal
Any PFI pin can externally input the SISOURCE signal, which is not
available as an output on the I/O connector. The onboard scan interval
counter uses the SISOURCE signal as a clock to time the generation of
the STARTSCAN signal. You must configure the PFI pin you select as
the source for the SISOURCE signal in the level-detection mode. You
can configure the polarity selection for the PFI pin for either active high
or active low.
National Instruments Corporation4-25PCI-6110E/6111E User Manual
Chapter 4Signal Connections
The maximum allowed frequency is 20 MHz, with a minimum pulse
width of 23 ns high or low. There is no minimum frequency limitation.
Either the 20 MHz or 100 kHz internal timebase generates the
SISOURCE signal unless you select some external source. Figure 4-20
shows the timing requirements for the SISOURCE signal.
t
p
t
t
w
w
t
= 50 ns minimum
p
t
= 23 ns minimum
w
Figure 4-20. SISOURCE Signal Timing
Waveform Generation Timing Connections
The analog group defined for the 611X E board is controlled by
WFTRIG, UPDATE*, and UISOURCE.
WFTRIG Signal
Any PFI pin can externally input the WFTRIG signal, which is available
as an output on the PFI6/WFTRIG pin.
As an input, the WFTRIG signal is configured in the edge-detection
mode. You can select any PFI pin as the source for WFTRIG and
configure the polarity selection for either rising or falling edge. The
selected edge of the WFTRIG signal starts the waveform generation for
the DACs. The update interval (UI) counter is started if you select
internally generated UPDATE*.
As an output, the WFTRIG signal reflects the trigger that initiates
waveform generation. This is true even if the waveform generation is
being externally triggered by another PFI. The output is an active high
pulse with a pulse width of 25 to 50 ns. This output is set to tri-state at
startup.
Figures 4-21 and 4-22 show the input and output timing requirements
for the WFTRIG signal.
t
w
Rising-edge
polarity
Falling-edge
polarity
t
= 10 ns minimum
w
Figure 4-21. WFTRIG Input Signal Timing
t
w
t
= 25-50 ns
w
Figure 4-22. WFTRIG Output Signal Timing
UPDATE* Signal
Any PFI pin can externally input the UPDATE* signal, which is
available as an output on the PFI5/UPDATE* pin.
As an input, the UPDATE* signal is configured in the edge-detection
mode. You can select any PFI pin as the source for UPDATE* and
configure the polarity selection for either rising or falling edge. The
selected edge of the UPDATE* signal updates the outputs of the DACs.
In order to use UPDATE*, you must set the DACs to posted-update
mode.
As an output, the UPDATE* signal reflects the actual update pulse that
is connected to the DACs. This is true even if the updates are being
externally generated by another PFI. The output is an active low pulse
with a pulse width of 50 to 75 ns. This output is set to tri-state at startup.
National Instruments Corporation4-27PCI-6110E/6111E User Manual
Chapter 4Signal Connections
Figures 4-23 and 4-24 show the input and output timing requirements
for the UPDATE* signal.
t
w
Rising-edge
polarity
Falling-edge
polarity
t
= 10 ns minimum
w
Figure 4-23. UPDATE* Input Signal Timing
t
w
t
= 50-75 ns
w
Figure 4-24. UPDATE* Output Signal Timing
The DACs are updated within 100 ns of the leading edge. Separate the
UPDATE* pulses with enough time that new data can be written to the
DAC latches.
The UI counter for the 611X E board normally generates the UPDATE*
signal unless you select some external source. The UI counter is started
by the WFTRIG signal and can be stopped by software or the internal
Buffer Counter.
D/A conversions generated by either an internal or external UPDATE*
signal do not occur when gated by the software command register gate.
UISOURCE Signal
Any PFI pin can externally input the UISOURCE signal, which is not
available as an output on the I/O connector. The UI counter uses the
UISOURCE signal as a clock to time the generation of the UPDATE*
signal. You must configure the PFI pin you select as the source for the
UISOURCE signal in the level-detection mode. You can configure the
polarity selection for the PFI pin for either active high or active low.
Figure 4-25 shows the timing requirements for the UISOURCE signal.
t
p
t
t
w
w
t
= 50 ns minimum
p
t
= 10 ns minimum
w
Figure 4-25. UISOURCE Signal Timing
The maximum allowed frequency is 20 MHz, with a minimum pulse
width of 10 ns high or low. There is no minimum frequency limitation.
Either the 20 MHz or 100 kHz internal timebase normally generates the
UISOURCE signal unless you select some external source.
General-Purpose Timing Signal Connections
The general-purpose timing signals are GPCTR0_SOURCE,
GPCTR0_GATE, GPCTR0_OUT, GPCTR0_UP_DOWN,
GPCTR1_SOURCE, GPCTR1_GATE, GPCTR1_OUT,
GPCTR1_UP_DOWN, and FREQ_OUT.
GPCTR0_SOURCE Signal
Any PFI pin can externally input the GPCTR0_SOURCE signal, which
is available as an output on the PFI8/GPCTR0_SOURCE pin.
As an input, the GPCTR0_SOURCE signal is configured in the
edge-detection mode. You can select any PFI pin as the source for
GPCTR0_SOURCE and configure the polarity selection for either
rising or falling edge.
As an output, the GPCTR0_SOURCE signal reflects the actual clock
connected to general-purpose counter 0. This is true even if another PFI
is externally inputting the source clock. This output is set to tri-state at
startup.
National Instruments Corporation4-29PCI-6110E/6111E User Manual
Chapter 4Signal Connections
Figure 4-26 shows the timing requirements for the GPCTR0_SOURCE
signal.
t
p
t
t
w
w
t
= 50 ns minimum
p
t
= 10 ns minimum
w
Figure 4-26. GPCTR0_SOURCE Signal Timing
The maximum allowed frequency is 20 MHz, with a minimum pulse
width of 10 ns high or low. There is no minimum frequency limitation.
The 20 MHz or 100 kHz timebase normally generates the
GPCTR0_SOURCE signal unless you select some external source.
GPCTR0_GATE Signal
Any PFI pin can externally input the GPCTR0_GATE signal, which is
available as an output on the PFI9/GPCTR0_GATE pin.
As an input, the GPCTR0_GATE signal is configured in the
edge-detection mode. You can select any PFI pin as the source for
GPCTR0_GATE and configure the polarity selection for either rising or
falling edge. You can use the gate signal in a variety of different
applications to perform actions such as starting and stopping the
counter, generating interrupts, saving the counter contents, and so on.
As an output, the GPCTR0_GATE signal reflects the actual gate signal
connected to general-purpose counter 0. This is true even if the gate is
being externally generated by another PFI. This output is set to tri-state
at startup.
Figure 4-27 shows the timing requirements for the GPCTR0_GATE
signal.
t
w
Rising-edge
polarity
Falling-edge
polarity
t
= 10 ns minimum
w
Figure 4-27. GPCTR0_GATE Signal Timing in Edge-Detection Mode
GPCTR0_OUT Signal
This signal is available only as an output on the GPCTR0_OUT pin.
The GPCTR0_OUT signal reflects the terminal count (TC) of
general-purpose counter 0. You have two software-selectable output
options—pulse on TC and toggle output polarity on TC. The output
polarity is software selectable for both options. This output is set to
tri-state at startup. Figure 4-28 shows the timing of the GPCTR0_OUT
signal.
TC
GPCTR0_SOURCE
GPCTR0_OUT
(Pulse on TC)
GPCTR0_OUT
(Toggle output on TC)
Figure 4-28. GPCTR0_OUT Signal Timing
GPCTR0_UP_DOWN Signal
This signal can be externally input on the DIO6 pin and is not available
as an output on the I/O connector. The general-purpose counter 0 will
count down when this pin is at a logic low and count up when it is at a
logic high. You can disable this input so that software can control the
up-down functionality and leave the DIO6 pin free for general use.
National Instruments Corporation4-31PCI-6110E/6111E User Manual
Chapter 4Signal Connections
GPCTR1_SOURCE Signal
Any PFI pin can externally input the GPCTR1_SOURCE signal, which
is available as an output on the PFI3/GPCTR1_SOURCE pin.
As an input, the GPCTR1_SOURCE signal is configured in the
edge-detection mode. You can select any PFI pin as the source for
GPCTR1_SOURCE and configure the polarity selection for either
rising or falling edge.
As an output, the GPCTR1_SOURCE monitors the actual clock
connected to general-purpose counter 1. This is true even if the source
clock is being externally generated by another PFI. This output is set to
tri-state at startup.
Figure 4-29 shows the timing requirements for the GPCTR1_SOURCE
signal.
t
p
t
w
Figure 4-29.
The maximum allowed frequency is 20 MHz, with a minimum pulse
width of 10 ns high or low. There is no minimum frequency limitation.
The 20 MHz or 100 kHz timebase normally generates the
GPCTR1_SOURCE unless you select some external source.
GPCTR1_GATE Signal
Any PFI pin can externally input the GPCTR1_GATE signal, which is
available as an output on the PFI4/GPCTR1_GATE pin.
As an input, the GPCTR1_GATE signal is configured in edge-detection
mode. You can select any PFI pin as the source for GPCTR1_GATE and
configure the polarity selection for either rising or falling edge. You can
use the gate signal in a variety of different applications to perform such
actions as starting and stopping the counter, generating interrupts,
saving the counter contents, and so on.
As an output, the GPCTR1_GATE signal monitors the actual gate
signal connected to general-purpose counter 1. This is true even if the
gate is being externally generated by another PFI. This output is set to
tri-state at startup.
Figure 4-30 shows the timing requirements for the GPCTR1_GATE
signal.
t
w
Rising-edge
polarity
Falling-edge
polarity
t
= 10 ns minimum
w
Figure 4-30. GPCTR1_GATE Signal Timing in Edge-Detection Mode
GPCTR1_OUT Signal
This signal is available only as an output on the GPCTR1_OUT pin.
The GPCTR1_OUT signal monitors the TC board general-purpose
counter 1. Yo u ha ve two softw are-selectable outp ut options— pulse on
TC and toggle output polarity on TC. The output polarity is software
selectable for both options. This output is set to tri-state at startup.
Figure 4-31 shows the timing requirements for the GPCTR1_OUT
signal.
National Instruments Corporation4-33PCI-6110E/6111E User Manual
Chapter 4Signal Connections
GPCTR1_UP_DOWN Signal
This signal can be externally input on the DIO7 pin and is not available
as an output on the I/O connector. General-purpose counter 1 counts
down when this pin is at a logic low and counts up at a logic high.
This input can be disabled so that software can control the up-down
functionality and leave the DIO7 pin free for general use. Figure 4-32
shows the timing requirements for the GATE and SOURCE input
signals and the timing specifications for the 611X E board OUT output
signals.
SOURCE
GATE
OUT
t
sc
V
IH
V
IL
t
gsu
V
IH
V
IL
V
OH
V
OL
Source Clock Period
Source Pulse Width
Gate Setup Time
Gate Hold Time
Gate Pulse Width
Output Delay Time
The GATE and OUT signal transitions shown in Figure 4-32 are
referenced to the rising edge of the SOURCE signal. This timing
diagram assumes that the counters are programmed to count rising
edges. The same timing diagram, but with the source signal inverted
and referenced to the falling edge of the source signal, would apply
when the counter is programmed to count falling edges.
The GATE input timing parameters are referenced to the signal at the
SOURCE input or to one of the internally generated signals on the
611XE board. Figure 4-32 shows the GATE signal referenced to the
rising edge of a source signal. The gate must be valid (either high or
low) for at least 10 ns before the rising or falling edge of a source signal
for the gate to take effect at that source edge, as shown by t
in Figure 4-32. The gate signal is not required to be held aft er the active
edge of the source signal.
If you use an internal timebase clock, the gate signal cannot be
synchronized with the clock. In this case, gates applied close to a source
edge take effect either on that source edge or on the next one. This
arrangement results in an uncertainty of one source clock period with
respect to unsynchronized gating sources.
The OUT output timing parameters are referenced to the signal at the
SOURCE input or to one of the internally g enerated clock signals on the
611X E board. Figure 4-32 shows the OUT signal referenced to the
rising edge of a source signal. Any OUT signal state changes occur
within 80 ns after the rising or falling edge of the source signal.
gsu
and tgh
FREQ_OUT Signal
This signal is available only as an output on the FREQ_OUT pin. The
frequency generator for the 611X E board outputs the FREQ_OUT pin.
The frequency generator is a 4-bit counter that can divide its input clock
by the numbers 1 through 16. The input clock of the frequency
generator is software-selectable from the internal 10 MHz and 100 kHz
timebases. The output polarity is software selectable. This output is set
to tri-state at startup.
Field Wiring Considerations
Environmental noise can seriously affect the accuracy of measurements
made with the 611X E board if you do not take proper care when
running signal wires between signal sources and the board. The
following recommendations apply mainly to analo g input signal routing
to the board, although they also apply to signal routing in general.
Minimize noise pickup and maximize measurement accuracy by taking
the following precautions:
•Use differential analog input connections to reject common-mode
noise.
•Use individually shielded, twisted-pair wires to connect analog
input signals to the board. With this type of wire, the signals
attached to the ACH+ and ACH– inputs are twisted together and
then covered with a shield. You then connect this shield only at one
National Instruments Corporation4-35PCI-6110E/6111E User Manual
Chapter 4Signal Connections
point to the signal source ground. This kind of connection is
required for signals traveling through areas with large magnetic
fields or high electromagnetic interference.
•Route signals to the board carefully. Keep cabling away from noise
sources. The most common noise source in a PCI data acquisition
system is the video monitor. Separate the monitor from the analog
signals as much as possible.
The following recommendations apply for all signal connections to the
611X E board:
•Separate the 611X E board signal lines from high-current or
high-voltage lines. These lines can induce currents in or voltages on
the 611X E board signal lines if they run in parallel paths at a close
distance. To reduce the magnetic coupling between lines, separate
them by a reasonable distance if they run in parallel, or run the lines
at right angles to each other.
•Do not run signal lines through conduits that also contain power
lines.
•Protect signal lines from magnetic fields caused by electric motors,
welding equipment, breakers, or transformers by running them
through special metal condui ts.
For more information, refer to the application note,
This chapter discusses the calibration procedures for your 611X E
board. If you are using the NI-DAQ device driver, that software
includes calibration functions for performing all of the steps in the
calibration process.
Calibration refers to the process of minimizing measurement and output
voltage errors by making small circuit adjustments. On the 611X E
board, these adjustments take the form of writing values to onboard
calibration DACs (CalDACs).
Some form of board calibration is required for all but the most forgiving
applications. If you do not calibrate your board, your signals and
measurements could have very large offset, gain, and linearity errors.
Three levels of calibration are available to you and described in this
chapter. The first level is the fastest, easiest, and least accurate;
whereas, the last level is the slowest, most difficult, and most accurate.
Loading Calibration Constants
5
The 611X E board is factory calibrated before shipment at
approximately 25° C to the levels indicated in Appendix A,
Specifications
were written to the CalDACs to achieve calibration in the factory—are
stored in the onboard nonvolatile memory (EEPROM). Because the
CalDACs have no memory capability, they do not retain calibration
information when the board is unpowered. Loading calibration
constants refers to the process of loading the CalDACs with the values
stored in the EEPROM. NI-DAQ software determines when this is
necessary and does it automatically. If you are not using NI-DAQ,
you must load these values yourself.
In the EEPROM there is a user-modifiable calibration area in addition
to the permanent factory calibration area. This means that you can load
the CalDACs with values either from the original factory calibration or
from a calibration that you subsequently performed.
National Instruments Corporation5-1PCI-6110E/6111E User Manual
. The associated calibration constants—the values that
Chapter 5Calibration
This method of calibration is not very accurate because it does not t ake
into account the fact that the board measurement and output voltage
errors can vary with time and temperature. It is better to self-calibrate
when the board is installed in the environment in which it will be used.
Self-Calibration
The 611X E board can measure and correct for almost all of its
calibration-related errors without any external signal connections. Your
National Instruments software provides a self-calibration method . This
self-calibration process, which generally takes less than a minute, is
thepreferred method of assuring accuracy in your application. Initiate
self-calibration to minimize the effects of any offset, gain, and linearity
drifts, particularly those due to warmup.
Immediately after self-calibration, the only significant residual
calibration error could be gain error due to time or temperature drift
ofthe onboard voltage reference. This error is addressed by external
calibration, which is discussed in the following section. If you are
interested primarily in relative measurements, you can ignore a small
amount of gain error, and self-calibration should be sufficient.
External Calibration
The 611X E board has an onboard calibration reference to ensurethe
accuracy of self-calibration. Its specifications are listed in AppendixA,
Specifications
stored in the EEPROM for subsequent self-calibrations. This voltage is
stable enough for most applications, but if you are using your board at
an extreme temperature or if the onboard reference has not been
measured for a year or more, you may wish to externally calibrate your
board.
An external calibration refers to calibrating your board with a known
external reference rather than relying on the onboard reference.
Redetermining the value of the onboard reference is part of this process
and the results can be saved in the EEPROM, so you should not have to
perform an external calibration very often. You can externally calibrate
your board by calling the NI-DAQ calibration function.
PCI-6110E/6111E User Manual5-2
. The reference voltage is measured at the factory and
To externally calibrate your board, be sure to use a very accurate
external reference. The reference should be several times more accurate
than the board itself. For example, to calibrate a 16-bit board, the
external reference should be at least ±0.001% (±10 ppm) accurate.
National Instruments CorporationA-3PCI-6110E/6111E User Manual
Full
Scale
±500.51%0.51%0.51%35 mV51
±200.51%0.51%0.51%20 mV20
±100.11%0.11%0.11%5.7 mV10
±10.057%0.058%0.059%0.7 mV1
±0.50.057%0.058%0.059%0.4 mV0.67
±0.20.057%0.058%0.059%0.2 mV0.39
Note: Accuracies are valid for measurements following an internal E Series calibra tion. Averaged numbers assume ditheri ng and av eraging of 100 single-channel readings.
Measurement accuracies are listed for operational temperatures within ±1° C of internal cali bration temperature and ±10° C of external or factory calibration temperature.
One year calibration interval recommended.
Appendix ASpecifications
Transfer Characteristics
INL .................................................... ±0.5 LSB typ, ±1 LSB max
DNL................................................... ±0.3 LSB typ, ±0.75 LSB max
Spurious free dynamic range (SFDR). See table, analog input
characteristics
Effective number of bits (ENOB)....... 11.0 bits, DC to 100 kHz
Offset error ........................................ See table, analog input
characteristics
Amplifier Characteristics
Input impedance................................. 1 MΩ in parallel with 100 pF
Input bias current ............................... ±200 pA
Input offset current ............................. ±100 pA
CMRR................................................ See table, analog input
characteristics
Dynamic Characteristics
Interchannel skew .............................. 1 ns typ
Bandwidth (0.5 to –3 dB)
Input range > ±0.2 V ................... 5 MHz
Input range = ±0.2 V ................... 4 MHz
System noise ...................................... See table, analog input
Crosstalk............................................–80 dB, DC to 100 kHz
Stability
Recommended warm-up time............. 15 min.
Offset temperature coefficient
Pregain ........................................ ±5 µV/° C
This appendix contains a list of commonly asked questions and their
answers relating to usage and special features of your 611X E board.
General Information
What is the 611X E board?
The 611X E board is a switchless and jumperless enhanced MIO board
that uses the DAQ-STC for timing.
What is the DAQ-STC?
The DAQ-STC is the system timing control application-specific
integrated circuit (ASIC) designed by National Instruments and is the
backbone of the 611X E board. The DAQ-STC contains seven 24-bit
counters and three 16-bit counters. The counters are divided into the
following three groups:
The groups can be configured independently with timing resolutions of
50 ns or 10 µs. With the DAQ-STC, you can interconnect a wide variety
of internal timing signals to other internal blocks. The interconnection
scheme is quite flexible and completely software configurable. New
capabilities such as buffered pulse generation, equivalent time
sampling, and seamlessly changing the sampling rate are possible.
What does sampling rate mean to me?
It means that this is the fastest you can acquire data on your board and
still achieve accurate results. The 611X E board has a sampling rate of
5 MS/s. This sampling rate is at 5 MS/s regardless if 1 or 4 channels are
acquiring data.
National Instruments CorporationC-1PCI-6110E/6111E User Manual
Appendix CCommon Questions
What type of 5V protection does the 611X E board have?
The 611X E board has 5 V lines equipped with a self-resetting 1 A fuse.
Installation and Configuration
How do you set the base address for the 611X E board?
The base address of the 611X E board is assigned automatically through
the PCI bus protocol. This assignment is completely transparent to you.
What jumpers should I be aware of when configuring my
611X E board?
The 611X E board is jumperless and switchless.
Which National Instruments document should I read first to get
started using DAQ software?
Your NI-DAQ or application software release notes documentation is
always the best starting place.
Analog Input and Output
I have connected a differential input signal, but my readings are
random and drift rapidly. What’s wrong?
Check your ground reference connections. Your signal may be
referenced to a level that is considered
board ground reference. Even if you are in differential mode, the signal
must
still be referenced to the same ground level as the board reference.
There are various methods of achieving this while maintaining a high
common-mode rejection ratio (CMRR). These methods are outlined in
Chapter4,
I’m using the DACs to generate a waveform, but I discovered with
a digital oscilloscope that there are glitches on the output signal. Is
this normal?
When it switches from one voltage to another, any DAC produces
glitches due to released charges. The largest glitches occur when the
most significant bit (MSB) of the D/A code switches. You can build a
lowpass deglitching filter to remove some of these glitches, depending
on the frequency and nature of your output signal.
Can I synchronize a one-channel analog input data acquisition with
a one-channel analog output waveform generation on my
611X E board?
Yes. One way to accomplish this is to use the waveform generation
timing pulses to control the analog input data acquisition. To do this,
follow steps 1 through 4 below, in addition to the usual steps for data
acquisition and waveform generation configuration.
•If you are using LabVIEW, invoke AI Clock Config VI with
clock source code set to PFI pin, high to low, and clock source
string set to 5.
3.Initiate analog input data acquisition, which will start only when
the analog output waveform generation starts.
4.Initiate analog output waveform generation.
Timing and Digital I/O
What types of triggering can be hardware-implemented on my
611X E board?
Hardware digital and analog triggering are both supported on the
611X E board.
What added functionality does the DAQ-STC make possible in
contrast to the Am9513?
The DAQ-STC incorporates much more than just 10 Am9513-style
counters within one chip. In fact, the DAQ-STC has the complexity of
more than 24 chips. The DAQ-STC makes possible PFI lines, analog
triggering, selectable logic level, and frequency shift keying. The
DAQ-STC also makes buffered operations possible, such as direct
National Instruments CorporationC-3PCI-6110E/6111E User Manual
Appendix CCommon Questions
up/down control, single or pulse train generation, equivalent time
sampling, buffered period, and buffered semiperiod measurement.
What is the difference in timebases between the Am9513
counter/timer and the DAQ-STC?
The DAQ-STC-based MIO boards have a 20 MHz time base. The
Am9513-based MIO boards have a 1 MHz or 5 MHz timebase.
Will the counter/timer applications that I wrote previously, work
with the DAQ-STC?
If you are using NI-DAQ with LabVIEW, some of your applications
drawn using the CTR VIs will still run. However, there are many
differences in the counters between the 611X E and other boards; the
counter numbers are different, timebase selections are different, and the
DAQ-STC counters are 24-bit counters (unlike the 16-bit counters on
boards without the DAQ-STC).
If you are using the NI-DAQ language interface or LabWindows/CVI,
the answer is no, the counter/timer applications that you wrote
previously will not work with the DAQ-STC. You must use the GPCTR
functions; ICTR and CTR functions will not work with the DAQ-STC.
The GPCTR functions have the same capabilities as the ICTR and CTR
functions, plus more, but you must rewrite the application with the
GPCTR function calls.
I’m using one of the general-purpose counter/timers on my
611X E board, but I do not see the counter/timer output on the I/O
connector. What am I doing wrong?
If you are using the NI-DAQ language interface or LabWindows/CVI,
you must configure the output line to output the signal to the I/O
connector. Use the
Select_Signal call in NI-DAQ to configure the
output line. By default, all timing I/O lines except EXTSTROBE* are
tri-stated.
What are the PFIs and how do I configure these lines?
PFIs are Programmable Function Inputs. These lines serve as
connections to virtually all internal timing signals.
If you are using the NI-DAQ language interface or LabWindows/CVI,
use the
PCI-6110E/6111E User ManualC-4
Select_Signal function to route internal signals to the I/O
connector, route external signals to internal timing sources, or tie
internal timing signals together.
If you are using NI-DAQ with LabVIEW and you want to connect
external signal sources to the PFI lines, you can use AI Clock Config,
AI Trigger Config, AO Clock Config, AO Trigger and Gate Config,
CTR Mode Config, and CTR Pulse Config advanced level VIs to
indicate which function the connected signal will serve. Use the Route
Signal VI to enable the PFI lines to output internal signals.
Caution:If you enable a PFI line for output, do not connect any external signal
!
source to it; if you do, you can damage the board, the computer, and the
connected equipment.
What are the power-on states of the PFI and DIO lines on the I/O
connector?
At system power-on and reset, both the PFI and DIO lines are set to high
impedance by the hardware. This means that the board circuitry is not
actively driving the output either high or low. However, these lines may
have pull-up or pull-down resistors connected to the m as shown in
Table 4-2. These resistors weakly pull the output to either a logic high
or logic low state. For example, DIO(0) will be in the high impedance
state after power on, and Table 4-2 shows that there is a 50 kΩ pull-up
resistor. This pull-up resistor will set the DIO(0) pin to a logic high
when the output is in a high impedance state.
National Instruments CorporationC-5PCI-6110E/6111E User Manual
Appendix
Customer Communication
For your convenience, this appendix contains forms to help you gather the information necessary
to help us solve your technical problems and a form you can use to comment on the product
documentation. When you contact us, we need the information on the Technical Support Form and
the configuration form, if your manual contains one, about your system configuration to answer your
questions as quickly as possible.
National Instruments has technical assistance through electronic, fax, and telephone systems to quickly
provide the information you need. Our electronic services include a bulletin board service, an FTP site,
a fax-on-demand system, and e-mail support. If you have a hardware or software problem, first try the
electronic support systems. If the information available on these systems does not answer your
questions, we offer fax and telephone support through our technical support centers, which are staffed
by applications engineers.
D
Electronic Services
Bulletin Board Support
National Instruments has BBS and FTP sites dedicated for 24-hour support with a collection of files
and documents to answer most common customer questions. From these sites, you can also download
the latest instrument drivers, updates, and example programs. For recorded instructions on how to use
the bulletin board and FTP services and for BBS automated information, call 512 795 6990. You can
access these services at:
United States: 512 794 5422
Up to 14,400 baud, 8 data bits, 1 stop bit, no parity
United Kingdom: 01635 551422
Up to 9,600 baud, 8 data bits, 1 stop bit, no parity
France: 01 48 65 15 59
Up to 9,600 baud, 8 data bits, 1 stop bit, no parity
FTP Support
To access our FTP site, log on to our Internet host, ftp.natinst.com, as anonymous and use
your Internet address, such as
documents are located in the
National Instruments CorporationD-1PCI-6110E/6111E User Manual
joesmith@anywhere.com, as your password. The support files and
/support directories.
Fax-on-Demand Support
Fax-on-Demand is a 24-hour information retrieval system containing a library of documents on a wide
range of technical information. You can access Fax-on-Demand from a touch-tone telephone at
512 418 1111.
E-Mail Support (Currently USA Only)
You can submit technical support questions to the applications engineering team through e-mail at the
Internet address listed below . Remember to include your name, address, and phone number so we can
contact you with solutions and suggestions.
support@natinst.com
Telephone and Fax Support
National Instruments has branch offices all over the world. Use the list below to find the technical
support number for your country. If there is no National Instruments office in your country, con tact
the source from which you purchased your software to obtain support.
Photocopy this form and update it each time you make changes to your software or hardware, and use
the completed copy of this form as a reference for your current configuration. Completing this form
accurately before contacting National Instruments for technical support helps our applications
engineers answer your questions more efficiently.
If you are using any National Instruments hardware or software products related to this problem,
include the configuration forms from their user manuals. Include additional pages if necessary.
Name ______________________________________________ ____________________________
Company _______________________________________________________________________
Address ________________________________________________________________________
_______________________________________________________________________________
Fax (___)___________________ Phone (___) _________________________________________
Computer brand ________________ Model ________________ Processor___________ ________
Operating system (include version number) ____________________________________________
Clock speed ______MHz RAM _____MB Display adapter __________________________
Mouse ___yes ___no Other adapters installed _______________________________________
Hard disk capacity _____MBBrand _____________________________________________
Instruments used _____________________________________________________________ ____
_______________________________________________________________________________
National Instruments hardware product model__________ Revision ______________________
Configuration ___________________________________________________________________
National Instruments software product ____________________________ Version ____________
Configuration ___________________________________________________________________
The problem is: __________________________________________________________________
_______________________________________________________________________________
List any error messages: ___________________________________________________________
_______________________________________________________________________________
The following steps reproduce the problem: __ ___ ____ ___________________________________
PCI-6110E/6111E Hardware and Software
Configuration Form
Record the settings and revisions of your hardware and software on the line to the right of each item.
Complete a new copy of this form each time you revise your software or hardware configuration, and
use this form as a reference for your current configuration. Completing this form accurately before
contacting National Instruments for technical support helps our applications engineers answer your
questions more efficiently.
National Instruments Products
PCI- 6 1 10E/6 1 1 1E board __________________________ __________ ______________ _________
PCI-6110E/6111E board serial number _______________________________________________
Base memory address of the PCI-6110E/6111E board ___________________________________
Interrupt level of the PCI-6110E/6111E board __________________________________________
National Instruments application software choice ________________________________________
Software version ______ ___________________________________________________ _________
Other Products
Computer make and model _________________________________________________________
Microprocessor ______________________________________ _____________________________
Clock frequency or speed ___________________________________________________________
Type of video board installed ____________________________________________ ____________
Operating system (DOS or Windows) _________________________________________________
Operating system version _________ __________________________________________________
Operating system mode ____________________________________________________________
Programming language ____________________________________________________________
Programming language version ______________________________________________________
Other boards in system ________________________________ _____________________________
Base memory address of other boards ________________ _________________________________
Interrupt level of other boards _______________________________________________________
Documentation Comment Form
National Instruments encourages you to comment on the documentation supplied with our products.
This information helps us provide quality products to meet your needs.
Title:PCI-6110E/6111E User Manual
Edition Date:April 1998
Part Number:321759B-01
Please comment on the completeness, clarity, and organization of the manual.
Thank you for your help.
Name _________________________________________________________________________
Title __________________________________________________________________________
Company _______________________________________________________________________
Address _____________________________________ ___________________________________
National Instruments CorporationG-1PCI-6110E/6111E User Manual
Glossary
–negative of, or minus
Ωohms
+5 V+5 VDC source signal
square root of
A
Aamperes
ACalternating current
ACHanalog input channel signal
ACH0GNDanalog input channel ground signal
A/Danalog-to-digital
ADCanalog-to-digital converter—an electronic device, often an
integrated circuit, that converts an analog voltage to a digital
number
AIanalog input
AIGATEanalog input gate signal
AIGNDanalog input ground signal
ANSIAmerican National Standards Institute
AOanalog output
AOGNDanalog output ground signal
ASICApplication-Specific Integrated Circuit—a proprietary
semiconductor component designed and manufactured to perform
a set of specific functions.
B
bipolara signal range that includes both positive and negative values
CCelsius
CalDACcalibration DAC
CHchannel—pin or wire lead to which you apply or from which you
read the analog or digital signal. Analog signals can be singleended or differential. For digital signals, you group channels to
form ports. Ports usually consist of either four or eight digital
channels
cmcentimeter
CMOScomplementary metal-oxide semiconductor
CMRRcommon-mode rejection ratio—a measure of an instrument’s
ability to reject interference from a common-mode signal, usually
expressed in decibels (dB)
CONVERT*convert signal
counter/timera circuit that counts external pulses or clock pulses (timing)
CTRcounter
D
D/Adigital-to-analog
DACdigital-to-analog converter—an electronic device, often an
integrated circuit, that converts a digital number into a
corresponding analog voltage or current
DAC0OUTanalog channel 0 output signal
DAC1OUTanalog channel 1 output signal
DAQdata acquisition—a system that uses the computer to collect,
receive, and generate electrical signals
DAQ-STCData acquisition system timing controller. An application-specific
integrated circuit (ASIC) for the system timing requirements of a
National Instruments CorporationG-3PCI-6110E/6111E User Manual
Glossary
general A/D and D/A system, such as a system containing the
National Instruments E Series boards.
dBdecibel—the unit for expressing a logarithmic measure of the ratio
of two signal levels: dB=20log10 V1/V2, for signals in volts
DCdirect current
DGNDdigital ground signal
DIdigital input
DIFFdifferential mode
DIOdigital input/output
DIPdual inline package
ditheringthe addition of Gaussian noise to an analog input signal
DMAdirect memory access—a method by which data can be transferred
to/from computer memory from/to a device or memory on the bus
while the processor does something else. DMA is the fastest
method of transferring data to/from computer memory.
DNLdifferential nonlinearity—a measure in least significant bit of the
worst-case deviation of code widths from their ideal value of 1 LSB
DOdigital output
E
EEPROMelectrically erasable programmable read-only memory—ROM that
can be erased with an electrical signal and reprogrammed
EXTSTROBEexternal strobe signal
F
FIFOfirst-in first-out memory buffer—FIFOs are often used on DAQ
devices to temporarily store incoming or outgoing data until that
data can be read or written. For example, an analog input FIFO
stores the results of A/D conversions until the data can be read into
system memory. Programming the DMA controller and servicing
interrupts can take several milliseconds in some cases. During this
time, data accumulates in the FIFO for future retrieval. With a
larger FIFO, longer latencies can be tolerated. In the case of analog
output, a FIFO permits faster update rates, because the waveform
data can be stored in the FIFO ahead of time. This again reduces the
effect of latencies associated with getting the data from system
memory to the DAQ device.
FREQ_OUTfrequency output signal
ftfeet
G
GATEgate signal
GPCTRgeneral-purpose counter signal
GPCTR0_GATEgeneral-purpose counter 0 gate signal
GPCTR0_OUTgeneral-purpose counter 0 output signal
Glossary
GPCTR0_SOURCEgeneral-purpose counter 0 clock source signal
GPCTR0_UP_DOWNgeneral-purpose counter 0 up down signal
GPCTR1_GATEgeneral-purpose counter 1 gate signal
GPCTR1_OUTgeneral-purpose counter 1 output signal
GPCTR1_SOURCEgeneral-purpose counter 1 clock source signal
GPCTR1_UP_DOWNgeneral-purpose counter 1 up down signal
National Instruments CorporationG-5PCI-6110E/6111E User Manual
Glossary
I
INLintegral nonlinearity–For an ADC, deviation of codes of the actual
transfer function from a straight line.
I/Oinput/output—the transfer of data to/from a computer system
involving communications channels, operator interface devices,
and/or data acquisition and control interfaces
I
OH
I
OL
current, output high
current, output low
K
kHzkilohertz
L
LEDlight emitting diode
LSBleast significant bit
M
mmeter
MBmegabytes of memory
MHzmegahertz
MIOmultifunction I/O
MITEMXI Interface to Everything
MSBmost significant bit
muxmultiplexer—a switching device with multiple inputs that
sequentially connects each of its inputs to its output, typically
at high speeds, in order to measure several signals with a single
analog input channel
NCnormally closed, or not connected
NI-DAQNational Instruments driver software for DAQ hardware
noisean undesirable electrical signal—Noise comes from external
sources such as the AC power line, motors, generators,