National Instruments AT-MIO-16X User Manual

AT-MIO-16X

User Manual

Multifunction I/O Board for the PC AT/EISA

October 1997 Edition

Part Number 320640B-01

© Copyright 1992, 1997 National Instruments Corporation. All rights reserved.

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Important Information

Warranty

The AT-MIO-16X is 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 Instru ments software ar e warranted not to fail to execute pro grammi ng
instructions, due to defects in materials and workmanship, for a period of 90 days from date of shipment, as evidenced
by receipts or other documentation. National Instruments will, at its option, repair or replace soft ware media that do
not execute programming instructions if National Instruments receives notice of such defects during the warranty
period. National Instrument s does not war rant that the oper ation of the softwar e shall be un interr upted 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 par ts whi ch are cov ered by w arranty .

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 ch anges to subsequent editions of this document without prior not ice to holders of th is edition. The
reader should consult National Instruments if errors are suspected. In no event shall National Instruments be liable for
any damages arising out of or related to this docum ent or the in format ion contai ned in it.

E

XCEPT AS SPECIFIED HEREIN

SPECIFICALLY DISCLAIMS ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE

C

USTOMER’S RIGHT TO RECOVER DAMAGES CAUSED BY FAULT OR NEGLIGENCE ON THE PART OF NATIONAL

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NSTRUMENTS SHALL BE LIMITED TO THE AMOUNT THERETOFORE PAID BY THE CUSTOMER
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

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against National Instruments must be brought wit hin one year after the cause of action accrues. Nat ion al Instrument s
shall not be liable for any delay in performan ce due to causes beyo nd it s reasonable cont rol. The warranty pr ovided
herein does not cover damages, defects, malf unctio ns, or s ervice fai lures caused by owne r’s fail ure to fol low the
National Instruments in sta llat ion, o perat ion, or ma inte na nce instr uct ions; owner ’s modif icat ion of the p roduct;
owner’s abuse, misuse, or neglige nt acts; and power failur e or surges , fire, floo d, acciden t, actions of third part ies,
or other events outside reasonable cont rol.

, N

ATIONAL INSTRUMENTS MAKES NO WARRANTIES, EXPRESS OR IMPLIED, AND

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ATIONAL INSTRUMENTS

. This limitation of the liability of National

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Under the copyright laws, this publication may not be reproduced or transmitted in any form, electronic or mechanical,
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Trademarks

ComponentWorks™, LabVIEW™, Meas ur e™, NI-DAQ™, RTSI™, and VirtualB ench™ are trademarks of National
Instruments C orporation.

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 design ed with comp onents and testing in tend ed to ensure a level o f reliabi lity
suitable for use in treatment and diag nosi s of humans . Appli cations of Nation al Instru men ts product s invol vin g
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 us e or applicat ion of Nat ional Ins trum ent s products for or involvi ng
medical or clinical treatment must be performed by properly trained and qualified medical personnel, and all 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 prod ucts ar e being used. National Instruments
products are NOT intended to be a substitute f or any for m of establ ished pr ocess, proce dure, or equi pmen t used to
monitor or safegua rd huma n he alth and sa fety in med ical or clin ical t reat ment .

About This Manual

Organization of This Manual........................................................................................xv

Conventions Used in This Manual................................................................................ xvi

Related Documentation.................................................................................................xvii

Customer Communication....... .....................................................................................xvii

Chapter 1
Introduction

About the AT-MIO-16X...............................................................................................1-1

Analog Input...................................................................................................1-2

Analog Output................................................................................................1-2

Digital and Timing I/O...................................................................................1-3

What You Need to Get Started.....................................................................................1-3

Software Programming Choices...................................................................................1-4

National Instruments Application Software...................................................1-4

NI-DAQ Driver Software...............................................................................1-5

Register-Level Programming.........................................................................1-6

Optional Equipment......................................................................................................1-7

Unpacking.....................................................................................................................1-7

Table

of

Contents

Chapter 2
Configuration and Installation

Board Configuration.....................................................................................................2-2

AT Bus Interface............................................................................................2-2

Base I/O Address Selection............................................................................2-3

Interrupt and DMA Channel Selection...........................................................2-7

Analog Input Configuration..........................................................................................2-7

Input Mode........................... ...... ...... ..............................................................2-7

DIFF Input (Eight Channels)...........................................................2-8

RSE Input (16 Channels).................................................................2-9

NRSE Input (16 Channels) ..............................................................2-9

Input Polarity and Input Range.......................................................................2-10

Considerations for Selecting Input Ranges......................................2-10

Analog Output Configuration.......................................................................................2-11

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National Instruments Corporation v AT-MIO-16X User Manual

Table of Contents

Digital I/O Configuration............................................................................................. 2-12

Board and RTSI Clock Configuration..........................................................................2-12

Hardware Installation ................................................................................................... 2-13

Signal Connections.......................................................................................................2-14

Field Wiring Considerations......................................................................................... 2-42

Cabling Considerations for the AT-MIO-16X with 50-Pin I/O Connector ................. 2-43

Cabling Considerations for the AT-MIO-16X with 68-Pin I/O Connector ................. 2-44

Analog Output Reference Selection...............................................................2-11

Analog Output Polarity Selection.................................................................. 2-12

Signal Connection Descriptions..................................................................... 2-17

Analog Input Signal Connections..................................................................2-19

Types of Signal Sources................................................................................. 2-21

Floating Signal Sources................................................................... 2-21

Ground-Referenced Signal Sources.................................................2-21

Input Configurations...................................................................................... 2-21

Differential Connection Considerations (DIFF Input

Configuration)............................................................................... 2-22

Differential Connections for Ground-Referenced Signal

Sources.......................................................................................... 2-23

Differential Connections for Nonreferenced or Floating

Signal Sources ..............................................................................2-24

Single-Ended Connection Considerations....................................... 2-26

Single-Ended Connections for Floating Signal Sources

(RSE Configuration).....................................................................2-27

Single-Ended Connections for Grounded Signal Sources

(NRSE Configuration).................................................................. 2-28

Common-Mode Signal Rejection Considerations........ ................... 2-29

Analog Output Signal Connections................................................................ 2-29

Digital I/O Signal Connections......................................................................2-31

Power Connections ........................................................................................ 2-32

Timing Connections for Data Acquisition and Analog Output..................... 2-33

SCANCLK Signal ........................................................................... 2-33

EXTSTROBE* Signal............................................ ...... ...... ............. 2-33

EXTCONV* Signal.........................................................................2-34

EXTTRIG* Signal............................................. ..... .........................2-35

EXTGATE* Signal.......................................................................... 2-36

EXTTMRTRIG* Signal.................................................................. 2-36

Counter Signal Connections............................................................2-37

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Chapter 3
Theory of Operation

Functional Overview.....................................................................................................3-1

PC I/O Channel Interface Circuitry..............................................................................3-2

Analog Input and Data Acquisition Circuitry...............................................................3-5

Analog Input Circuitry ...................................................................................3-6

Data Acquisition Timing Circuitry................................................ ..... ............3-8

Multiple-Channel Data Acquisition ...............................................................3-12

Analog Output and Timing Circuitry.............................................................3-15

DAC Waveform Circuitry and Timing...........................................................3-18

Digital I/O Circuitry......................................................................................................3-24

Timing I/O Circuitry.....................................................................................................3-25

RTSI Bus Interface Circuitry ........................................................................................ 3-29

Table of Contents

A/D Converter..................................................................................3-6

Analog Input Multiplexers............................................................... 3-6

Analog Input Configuration............................................................. 3-6

PGIA ................................................................................................3-7

ADC FIFO Buffer.............. ..... ...... ...................................................3-7

Analog Input Calibration .................................................................3-7

Single-Read Timing........... ..... .........................................................3-8

Single-Channel Data Acquisition Timing........................................3-9

Continuous Scanning Data Acquisition Timing..............................3-13

Interval Scanning Data Acquisition Timing ....................................3-14

Data Acquisition Rates.....................................................................3-15

Analog Output Circuitry..................................................................3-16

Analog Output Configuration..........................................................3-17

Analog Output Calibration...............................................................3-17

DAC Waveform Circuitry................................................................3-18

DAC Waveform Timing Circuitry....................................... ...... ......3-20

FIFO Continuous Cyclic Waveform Generation.............................3-22

FIFO Programmed Cyclic Waveform Generation...........................3-23

FIFO Pulsed Waveform Generation ................................................3-23

Chapter 4
Register Map and Descriptions

Register Map.................................................................................................................4-1

Register Sizes .................................................................................................4-3

Register Description Format...........................................................................4-3

Configuration and Status Register Group.......................................................4-4

Command Register 1........................................................................4-5

Command Register 2........................................................................4-9

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National Instruments Corporation vii AT-MIO-16X User Manual

Table of Contents

Command Register 3.......................................................................4-13

Command Register 4.......................................................................4-20

Status Register 1.............................................................................. 4-25

Status Register 2.............................................................................. 4-30

Analog Input Register Group......................................................................... 4-31

ADC FIFO Register..................................... ...... ..............................4-32

CONFIGMEM Register .................................................................. 4-35

Analog Output Register Group......................................................................4-41

DAC0 Register ................................................................................4-44

DAC1 Register ................................................................................4-45

ADC Event Strobe Register Group............................................. ...... ............. 4-46

CONFIGMEMCLR Register........................................................... 4-47

CONFIGMEMLD Register............................................................. 4-48

DAQ Clear Register.........................................................................4-49

DAQ Start Register..........................................................................4-50

Single Conversion Register.................... ..... ...... ..............................4-51

ADC Calibration Register ....................................................... ........ 4-52

DAC Event Strobe Register Group............................................. ...... ............. 4-53

TMRREQ Clear Register.................................................................4-54

DAC Update Register................................................... ...... ............. 4-55

DAC Clear Register..................................... ...... ..............................4-56

General Event Strobe Register Group............................................................4-57

DMA Channel Clear Register..........................................................4-58

DMATCA Clear Register................................................... ..... ...... ..4-59

DMATCB Clear Register................................................................4-60

External Strobe Register..................................................................4-61

Calibration DAC 0 Load Register ................................ ...... ..... ........ 4-62

Calibration DAC 1 Load Register ................................ ...... ..... ........ 4-63

Am9513A Counter/Timer Register Group....................................................4-64

Am9513A Data Register ................................................................. 4-65

Am9513A Command Register........................................................4-66

Am9513A Status Register............................................................... 4-67

Digital I/O Register Group............................................................................. 4-68

Digital Input Register ...................................................................... 4-69

Digital Output Register....................................................................4-70

RTSI Switch Register Group......................................................................... 4-71

RTSI Switch Shift Register .............................................................4-72

RTSI Switch Strobe Register........................................................... 4-73

AT-MIO-16X User Manual viii

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National Instruments Corporation

Chapter 5
Programming

Data Acquisition Programming Functions ...................................................................5-14

Programming the Digital I/O Circuitry.........................................................................5-36

Programming the Am9513A Counter/Timer................................................................5-37

RTSI Bus Trigger Line Programming Considerations .................................................5-37

Table of Contents

Register Programming Considerations...........................................................5-1

Resource Allocation Considerations............................ ..... ...... .......................5-1

Initializing the AT-MIO-16X.........................................................................5-2

Initializing the Am9513A ................................................................5-3

Programming the Analog Input Circuitry.......................................................5-5

Single Conversions Using the SCONVERT or

EXTCONV* Signal ......................................................................5-5

Generating a Single Conversion.....................................................................5-6

Reading a Single Conversion Result..............................................................5-7

Programming Single-Channel Data Acquisition Sequence............................5-7

Programming Data Acquisition Sequences with Channel Scanning..............5-10

Continuous Channel Scanning Data Acquisition.............................5-10

Interval-Channel Scanning Data Acquisition.................................................5-12

Clearing the Analog Input Circuitry...............................................................5-14

Programming Single-Analog Input Channel Configurations.........................5-15

Programming Multiple-Analog Input Channel Configurations .....................5-15

Programming the Sample-Interval Counter....................................................5-16

Programming the Sample Counter(s).............................................................5-17

Sample Counts 2 through 65,536.....................................................5-18

Sample Counts Greater than 65,536 ................................................5-18

Programming the Scan-Interval Counter........................................................5-20

Applying a Trigger.........................................................................................5-21

Servicing the Data Acquisition Operation......................................................5-22

Resetting the Hardware after a Data Acquisition Operation..........................5-22

Resetting a Single Am9513A Counter/Timer..................................5-23

Programming the Analog Output Circuitry....................................................5-25

Cyclic Waveform Generation.........................................................................5-26

Programmed Cycle Waveform Generation....................................................5-28

Pulsed Cyclic Waveform Generation.............................................................5-30

Waveform Generation Programming Functions............................................5-32

Clearing the Analog Output Circuitry..............................................5-32

Selecting the Internal Update Counter.............................................5-32

Programming the Update-Interval Counter.................................................... 5-32

Programming the Waveform Cycle Counter..................................................5-34

Programming the Waveform Cycle Interval Counter ....................................5-34

Servicing Update Requests..............................................................5-35

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National Instruments Corporation ix AT-MIO-16X User Manual

Table of Contents

RTSI Switch Signal Connection Considerations.......................................................... 5-38

Programming the RTSI Switch .................................................................................... 5-39

Programming DMA Operations..................................................................... 5-41

Interrupt Programming................................................................................... 5-43

Chapter 6
Calibration Procedures

Calibration Equipment Requirements........................... ...... ......................................... 6-7

Calibration DACs.........................................................................................................6-8

Reference Calibration................................................................................................... 6-8

Analog Input Calibration.............................................................................................. 6-9

Analog Output Calibration........................................................................................... 6-10

Appendix A
Specifications

Appendix B
I/O Connector

Appendix C
AMD Am9513A Data Sheet

Appendix D
Customer Communication

Glossary

Index

Figures

Figure 1-1. The Relationship between the Programming Environment,

NI-DAQ, and Your Hardware.......... ...... ............................................... 1-6

Figure 2-1. AT-MIO-16X with 50-Pin I/O Connector Parts Locator Diagram....... 2-1

Figure 2-2. AT-MIO-16X with 68-Pin I/O Connector Parts Locator Diagram....... 2-2

Figure 2-3. Example Base I/O Address Switch Settings.......................................... 2-3

Figure 2-4. AT-MIO-16X 50-Pin I/O Connector.....................................................2-15

AT-MIO-16X User Manual x

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National Instruments Corporation

Table of Contents

Figure 2-5. AT-MIO-16X 68-Pin I/O Connector.....................................................2-16

Figure 2-6. AT-MIO-16X PGIA ..............................................................................2-20

Figure 2-7. Differential Input Connections for Ground-Referenced Signals...........2-23

Figure 2-8. Differential Input Connections for Nonreferenced Signals...................2-24

Figure 2-9. Single-Ended Input Connections for Nonreferenced or

Floating Signals .....................................................................................2-27

Figure 2-10. Single-Ended Input Connections for Ground-Referenced Signals........2-28

Figure 2-11. Analog Output Connections...................................................................2-30

Figure 2-12. Digital I/O Connections......................................................................... 2-32

Figure 2-13. EXTSTROBE* Signal Timing..............................................................2-33

Figure 2-14. EXTCONV* Signal Timing ..................................................................2-34

Figure 2-15. EXTTRIG* Signal Timing....................................................................2-35

Figure 2-16. EXTTMRTRIG* Signal Timing............................................................2-36

Figure 2-17. Event-Counting Application with External Switch Gating...................2-38

Figure 2-18. Frequency Measurement Application....................................................2-39

Figure 2-19. General-Purpose Timing Signals...........................................................2-41

Figure 3-1. AT-MIO-16X Block Diagram...............................................................3-1

Figure 3-2. PC I/O Channel Interface Circuitry Block Diagram..............................3-3

Figure 3-3. Analog Input and Data Acquisition Circuitry Block Diagram..............3-5

Figure 3-4. ADC Conversion Timing.......................................................................3-8

Figure 3-5. Single-Channel Posttrigger Data Acquisition Timing...........................3-10

Figure 3-6. Single-Channel Pretrigger Data Acquisition Timing.............................3-11

Figure 3-7. Scanning Posttrigger Data Acquisition Timing.....................................3-13

Figure 3-8. Interval Scanning Posttrigger Data Acquisition Timing........................3-14

Figure 3-9. Analog Output Circuitry Block Diagram...............................................3-16

Figure 3-10. Analog Output Waveform Circuitry......................................................3-19

Figure 3-11. Posted DAC Update Timing..................................................................3-20

Figure 3-12. Analog Output Waveform Circuitry......................................................3-21

Figure 3-13. FIFO Cyclic Waveform Generation with Disable.................................3-22

Figure 3-14. FIFO Programmed Cyclic Waveform Timing.......................................3-23

Figure 3-15. FIFO Pulsed Waveform Generation Timing .........................................3-23

Figure 3-16. Digital I/O Circuitry Block Diagram.....................................................3-24

Figure 3-17. Timing I/O Circuitry Block Diagram....................................................3-26

Figure 3-18. Counter Block Diagram.........................................................................3-27

Figure 3-19. RTSI Bus Interface Circuitry Block Diagram.......................................3-29

Figure 5-1. Initializing the Am9513A Counter/Timer.............................................5-4

Figure 5-2. Single Conversion Programming...........................................................5-6

Figure 5-3. Single-Channel Data Acquisition Programming...................................5-9

Figure 5-4. Scanning Data Acquisition Programming.............................................5-11

Figure 5-5. Interval Scanning Data Acquisition Programming................................5-13

Figure 5-6. Resetting an Am9513A Counter/Timer.................................................5-24

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Table of Contents

Figure 5-7. Cyclic Waveform Programming ........................................................... 5-27

Figure 5-8. Programmed Cycle Waveform Programming....................................... 5-29

Figure 5-9. Pulsed Cyclic Waveform Programming................................................5-31

Figure 5-10. RTSI Switch Control Pattern.................................................................5-40

Figure 6-1. AT-MIO-16X EEPROM Map ............................................................... 6-2

Figure 6-2. Revision and Subrevision Field............................................................. 6-5

Figure 6-3. Configuration Memory Depth Field...................................................... 6-5

Figure 6-4. ADC and DAC FIFO Depth Field......................................................... 6-6

Figure 6-5. Area Information Field..........................................................................6-6

Figure B-1. AT-MIO-16X 50-Pin I/O Connector............................................. ...... ..B-2

Figure B-2. AT-MIO-16X 68-Pin I/O Connector............................................. ...... ..B-3

Tables

Table 2-1. Default Settings of National Instruments Products for the PC.............. 2-4

Table 2-2. Switch Settings with Corresponding Base I/O Address and

Table 2-3. Available Input Configurations for the AT-MIO-16X..........................2-8

Table 2-4. Actual Range and Measurement Precision Versus Input Range

Table 2-5. Recommended Input Configurations for Ground-Referenced and

Base I/O Address Space........................................................................2-5

Selection and Gain.................................................................................2-11

Floating Signal Sources......................................................................... 2-22

Table 4-1. AT-MIO-16X Register Map..................................................................4-1

Table 4-2. DMA Channel Selection ....................................................................... 4-12

Table 4-3. DMA and Interrupt Modes....................................................................4-16

Table 4-4. Interrupt Level Selection.......................................................................4-19

Table 4-5. Board and RTSI Clock Selection..........................................................4-21

Table 4-6. Analog Output Waveform Modes......................................................... 4-22

Table 4-7. Straight Binary Mode A/D Conversion Values..................................... 4-33

Table 4-8. Two’s Complement Mode A/D Conversion Values............................. 4-34

Table 4-9. Input Configuration...............................................................................4-39

Table 4-10. Analog Output Voltage Versus Digital Code (Unipolar Mode)............ 4-42

Table 4-11. Analog Output Voltage Versus Digital Code (Bipolar Mode) .............. 4-42

Table 5-1. Am9513A Counter/Timer Allocations..................................................5-2

Table 5-2. RTSI Switch Signal Connections.......................................................... 5-38

Table 6-1. EEPROM Factory Area Information..................................................... 6-2

Table 6-2. Calibration DACs..................................................................................6-8

AT-MIO-16X User Manual xii

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National Instruments Corporation

Table of Contents

Table A-1. Equivalent Offset Errors in 16-Bit Systems ..........................................A-3

Table A-2. Equivalent Gain Errors in 16-Bit Systems.............................................A-4

Table A-3. Typical Multiple-Channel Scanning Settling Times .............................A-5

Table B-1. Signal Connection Descriptions............................................................. B-4

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National Instruments Corporation xiii AT-MIO-16X User Manual

This manual describes the mechanical and electrical aspects of the
AT-MIO-16X board and contains information concerning its operation
and programming. Th e A T-M IO -16X is a high-pe rf orman ce,
multifunction analog, digital, and timing I/O board for the IBM PC AT
and compatibles and EISA perso nal comp uters (PCs).

Organization of This Manual

The AT-MIO-16X Us er Man ual is orga nized a s fo llows:

• Chapter 1, Introduction, describes the AT-MIO-16X, lists the
contents of your AT -M IO-1 6X kit, the o ptiona l so ftware, and
optional equipment, and explains how to unpack the AT-MIO-16X.

• Chapter 2, Configuration and Installation, ex plains bo ar d
configuration, installation of the AT-MIO-16X into the PC, signal
connections to the AT -MIO -1 6X, an d ca ble c onsid eration s.

• Chapter 3, Theory of Operation, contains a functional overvie w of
the AT-MIO-16X and explains the operation of each functional unit
making up the AT-MIO - 16X.

• Chapter 4, Register Map a nd D escriptions , describes in detail the
address and function of each of the AT-MIO-16X control and status
registers.

• Chapter 5, Programming, contains program ming instruc tions f or
operating the circuitry on the AT-MIO-1 6X.

• Chapter 6, Calibration Procedures, discusses the calibration
resources and proc edur es fo r the A T-MI O-16 X an alog in put a nd
analog output circuitry.

• Appendix A, Specifications, lists the specifications of the
AT-MIO-16X.

• Appendix B, I/O Connector, describes the pinout and signal names
for the AT-MIO-16X 50-pin I/O conn ector and the 68 -pin I/O
connector.

About

This

Manual

©

National Instruments Corporation xv AT-MIO-16X User Manual

About This Manual

• Appendix C, AMD Am9513A Data Sheet, contains the
manufacturer data shee t f or the AM D Am95 13A System T iming
Controller integrated circuit (Advanced Micro Devices, Inc.). This
controller i s use d on the A T-M IO -1 6X.

• Appendix D, Customer Communication, contains forms you can
use to request help from National Instruments or to comment on our
products.

•The Glossary contains an alphabetical list and description of terms
used in this manual, including abbreviations, acronym s, metric
prefixes, mnemonics, and symbols.

•The Index cont ains an alphabet ical li st of key terms and topics used
in this manual, including the page where you can find each one.

Conventions Used in This Manual

The following conventions are used in this manual:

<> Angle brackets containing numbers separated by an ellipsis represent a

range of values associated with a bit or signal name (for exam ple,
DBIO<3..0>).

This icon to the left of bold italicized text denotes a note, which alerts
you to important information.

!

bold italic Bold italic text denotes a note, caution, or warning.

italic Italic text denotes emphasis, a cross reference, or an introduction to a

NI-DAQ NI-DAQ is used throughout this manual to refer to the NI-DAQ

PC PC refers to the IBM PC AT and compatibles, and to EISA personal

AT-MIO-16X User Manual xvi

This icon to the left of bold italicized text denotes a caution, which
advises you of precau tions to take to av oid injury , d ata lo ss, or a
system crash.

key concept.

software for DOS/Windows/LabWindo ws unless otherwise no ted.

computers.
The Glossary lists abbreviations, acronyms, metric prefixes,

mnemonics, symbols, and ter ms.

©

National Instruments Corporation

Related Documentation

The following document contains information that you may find helpful
as you read this manual:

• IBM Personal Computer AT Technical Reference
You may also want to consult the following Advanced Micro D evices

information if you plan to prog ram the Am9 513 A Coun ter/Ti mer u sed
on the AT-MIO-16X:

• Am9513A/Am9513 System Timing Controller

Customer Communication

National Instruments want to receive your co mments on ou r 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 for ms are in
Appendix D, Customer Communication, at the end of this manual.

About This Manual

©

National Instruments Corporation xvii AT-MIO-16X User Manual

Chapter

Introduction

This chapter describes the AT-MIO-16X, lists the contents of your
AT-MIO-16X kit, the optional sof tware, an d optional equi pment, and
explains how to unpack the AT-MI O-16 X.

About the AT-MIO-16X

Congratulations on your p urcha se of the Na tional I nstrume nts
AT-MIO-16X. The AT -MIO-1 6X is a high-perf ormance ,
software-configurable 16-bit DAQ board for laboratory, test and
measurement, and data ac quisition and contro l a pplication s. The
board performs high-accu racy measurements with self-calibration,
high-speed settling to 16 bits, noise as low as 0.8 LSBrms, and a
maximum DNL of ±0.5 LSB . Because of its large FIFO s and
dual-channel DMA, the AT-MIO-16X can achieve high performance,
even when used in environments that may have long interrupt latencies,
such as Windows.

Because off-the-shelf instrumentation amplifiers require 500 µsec and
more to settle to 16-bit accuracy at high gains when sampling multiple
channels , Na t i o nal Instruments devel o pe d the NI-PGIA. The NI-PGIA,
which is used on the AT-MIO-16X, is an instrumentation amplifier that
settles to 16 bits in 40 µs, even when the board is used at its high est gain
of 100.

1

A common problem with DAQ boards is that you cannot easily
synchronize several mea sur em ent fu nctio ns to a c ommon trig ger o r
timing event. The AT -MI O- 1 6X has the Real-Time System Integ rat io n
(RTSI) bus to solve this pr oble m. T he RT SIbus co nsists of our custom
RTSI bus interface chip and a ribbon cable to route timing and trigger
signals between several functions on one or more DAQ boa rds in
your PC.

The AT-MIO-16X can interface to the Signal Conditioning eXtensions
for Instrumentation (SCXI) system so that you can acquire over 3,000
analog signals from therm oco uples, RT Ds , strain ga ug es, v oltag e
sources, and curr en t sou rc es . You c a n also ac qu ire or ge nera te dig ital

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National Instruments Corporation 1-1 AT-MIO-16X User Manual

Chapter 1 Introduction

Analog Input

signals for communication and control. SCXI is the instrumentation
front end for plug-in DA Q b oards .

The AT-MIO-16X is a high-performance multifunction analog, digital,
and timing I/O boar d for the PC. The AT-M IO- 16X has a 10 µsec,
16-bit, sampling ADC that can monitor a single input channel, or scan
through the 16 single-ended or 8 differential channels (expandable with
National Instruments multiplexing products) at a programmable gain of
1, 2, 5, 10, 20, 50, o r 100 fo r unipo lar or bip olar inp ut r ange s. A
512-word ADC FIFO buffer can perform seamless data acquisition at
the maximum rate without data loss. Internal or external triggering and
sampling are supported. If signal conditioning or additional analog
inputs are required, you can use the SCXI signal conditioning modules,
SCXI multiplexer products, or the AMUX-64T multiplexer board.

You can use the NI-DAQ software included with the AT-MIO-16X to
calibrate the analog input circuitry. This software adjusts the offset
and gain errors to zero by means of board-level calibration DACs. You
can store calibration DAC constants resulting from the calibration
procedure in the onboard EEPROM for later use. See Chapter 6,
Calibration Procedures, for additional information on calibration
procedures for the AT-MIO-16X.

Analog Output

The AT-MIO-16X also has two deglitched, double-buffered,
multiplying, 16-bit DACs that may be configured for a unipolar or
bipolar voltage output range . An o nbo ar d, + 10-V refe renc e is th e
internal reference to the circuitry of the DAC. A 2,048-word DAC FIFO
buffer allows seamless wavefo rm genera tion at the maximum ra te
without data loss. The DAC FIFO can perform cyclic waveform
generation directly from the FIFO, independent of the PC interface.
You can use the analog output circuitry for internal timer an d external
signal update capability for waveform generation.

You calibrate the analog output circuitry through the NI-DAQ software
provided with the boar d. Th is soft ware a djusts th e DAC offset and gain
errors of each channel to zero by means of board-level calibration
DACs. Calibration DAC constants resulting from the calibration
procedure may be stored in the onboard EEPROM for later use. See
Chapter 6, Calibration Procedures, for additio nal info rmati on on
calibration pro ce du res f or t he AT -M IO-1 6X .

AT-MIO-16X User Manual 1-2

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National Instruments Corporation

Digital and Timing I/O

In addition to the analog input and analog output capabilities of the
AT-MIO-16X, the AT-MIO -16X al so ha s ei ght digital I/O lines th at
can sink up to 24 mA of current, and three independe nt 16-bit
counter/timers for frequency counting, event counting, and pulse
output applications. The AT-MIO-16X has timer-generated inte rrupts,
a high-performance RTSI bus interface, and four triggers for
system-level timing.

You can use the AT-MIO-16X, with its multifunction analog, digital,
and timing I/O, in many applications, including machine and process
control automation, level monitoring and control, instrumentation,
electronic testing, and many others. You can use the multichannel
analog input for signal and transient analysis, data logging, and
chromatography. The tw o ana log outp ut cha nnels a re use ful for
machine and process co ntro l, a nalog fu nc tion g en eration, 16- bit
resolution voltage source, and pro grammab le signal attenu ation. You
can use the eight TTL-compatible digital I/O lines for machine and
process control, intermac hine co mmunic ation, and r elay switching
control. The three 16-bit counter/timers are useful for such functions
as pulse and clock gener ation , time d con trol o f labo ratory equipm e nt,
and frequency, event, and pulse-width measurement. With all these
functions on one bo ard, yo u ca n au to matica lly m onitor and co ntro l
laboratory processes.

Chapter 1 Introduction

The AT-MIO-16X is interfaced to the National Instruments RTSI bus.
With this bus, National Instru ments A T Se ries b oa rds ca n se nd timing
signals to each other. T he A T-M IO-16 X can send sign als from th e
onboard counter/timer to another board, or another board can control
single and multiple A/D con version s on the AT -MIO -16X .

Detailed specifications for the AT-MIO-16X are listed in Appendix A,
Specifications.

What You Need to Get Started

To set up and use y our AT -MIO -16X Serie s b oa rd, y ou will nee d the
following:

❑ One of the following boards:

AT-MIO-16X 50-pin
AT-MIO-16X 68-pin

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National Instruments Corporation 1-3 AT-MIO-16X User Manual

Chapter 1 Introduction

AT-MIO-16X User Man ual

❑
❑ One of the following software packages and documentation:

ComponentWorks
LabVIEW for Windows
LabWindows/CVI fo r W indo ws
Measure
NI-DAQ for PC Compatibles
VirtualBen ch

❑ Your comp uter

Software Programming Choices

You have several options to choose from w hen progra mming you r
National Instruments DAQ and SCXI hardware. You can use National
Instruments application software, NI-DAQ, or register-level
programming.

National Instruments Application Software

ComponentWorks con tains tools for data acq uisition and instr ument
control built on NI-DAQ driver softw are. Component Works provide s a
higher-level programming interface for building virtual instruments
through standard OLE controls and DLLs. With ComponentWorks, 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 po werf ul g raphic al progr am ming langua ge. The
LabVIEW Data Acquisition VI L ibra r y, a se ries of V Is fo r using
LabVIEW with National Instruments DAQ hardware, is included with
LabVIEW. The LabVIEW D ata A cquisitio n VI Libr ar y is functiona lly
equivalent to NI-DAQ software.

LabWindows/CVI features interactive graphics, state-of-the-art user
interface, and uses th e ANSI standa rd C pr ogr am ming la nguage . The
LabWindows/CVI Data Ac quisition Lib rary, a se ries of fun ctions f or
using LabWindows/CVI with National Instruments DAQ hardware, is
included with the NI-DAQ software kit. The LabWindow s/CVI Data
Acquisition Library is functionally equivalent to the NI-D AQ sof twar e.

AT-MIO-16X User Manual 1-4

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National Instruments Corporation

VirtualBench features virtual instruments that combine DAQ products,
software, and your co mputer to creat e a stand-alone in strument with the
added benefit of the processing, display, and storage capabilities of
your computer. VirtualBench instruments load and save waveform data
to disk in th e s ame form s th at ca n be u sed i n pop ular sp re ad she et
programs and w ord proc e ssors.

Using ComponentWork s, LabVIE W, LabWindo ws /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 sof tware is included at no ch ar ge 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 ap plicatio n
programmin g enviro nment. These func tions in clude r outines for anal og
input (A/D conversion), buffered data acquisition (high-sp eed A/D
conversion), analog outp ut ( D/A con version ), wavef orm g eneration
(timed D/A conversion), digital I/O, counter/timer operations, SCXI,
RTSI, self-calibration, messaging, and acquiring data to extended
memory.

Chapter 1 Introduction

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. Ex am ples of h igh- leve l func tions are stre aming data to
disk or acquiring a certain number of data po ints. An examp le 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.

NI-DAQ also internal ly addr esses many of the co mplex i ssues bet wee n
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 platforms
with minimal modifications to your code. Whether you are using
conventional programming lan guages o r Na tional I nstrum ents
application software, your ap plication use s the NI-DAQ driv er
software, as illustrated in Figure 1-1.

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National Instruments Corporation 1-5 AT-MIO-16X User Manual

Chapter 1 Introduction

Programming Environment

SCXI Hardware

Figure 1-1. The Relationship between the Programming Environment,

Register-Level Programming

The final option for programming any National Instruments DAQ
hardware is t o wr it e r eg iste r- lev el softw are . Writ ing re gist er-l ev el
programming software can be very time-c on sum ing and ine ffi cient,
and is not recomm en de d f or mo st u s ers .

Conventional

DAQ or

ComponentWorks,

LabVIEW,

LabWindows/CVI, or

VirtualBench

NI-DAQ

Driver Software

Personal

Computer or

Workstation

NI-DAQ, and Your Hardware

Even if you are an experienced register-level programmer, using
NI-DAQ or applica tion sof tware to pro gram you r Nation al Inst rume nts
DAQ hardware is ea sier than, and as flexib le as, regi ster- lev el
programming, and can sa ve w ee ks of deve lopment time.

AT-MIO-16X User Manual 1-6

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National Instruments Corporation

Optional Equipment

National Instruments offers a var iety of pr odu cts to use w ith yo ur
AT-MIO-16X board, inclu ding cables, c onnector bloc ks, and other
accessories, as follows:

• Cables and cable assemblies, shielded and ribb on

• Connector blocks, shield ed and uns hielde d 50 a nd 68-pin scr ew
terminals

• Real Time System Integration (RTSI) bus cables

• SCXI modules and accessories for isolating, amplifying, exciting,
and multiplexing signals for relays and analog output. With SCXI
you can condition and acquire up to 3,072 channels.

• Low channel count signa l con ditioning module s, bo ards, and
accessories, including co nditionin g for strain ga uges a nd RT Ds,
simultaneous sample and ho ld, and re lays

For more specific information about these products, refer to your
National Instruments catalogue or call the office nearest you.

Chapter 1 Introduction

Unpacking

Your AT-MIO-16X board is shipped in an antistatic package to prevent
electrostatic damage to the board. Electrostatic discharge can damage
several com ponents on the board. To avoid such damage in handling the
board, take the following pre cautions:

• Ground yourself via a ground ing strap or by hold ing 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 fro m the package and in spect the board for loose
components or an y o ther sig n o f dama ge. No tif y Nationa l
Instruments if the board appears da maged in any way. Do not
install a damaged board into your computer.

• Never touch the exposed pins of connectors.

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National Instruments Corporation 1-7 AT-MIO-16X User Manual

Configuration and

Chapter

Installation

1

2

This chapter explains board configuration, installation of the
AT-MIO-16X into the PC, signal connections to the AT-MIO-16X,
and cable considerations.

234

1 Product Name, Assembly Number, and Revision Letter 2Fuse 3 U112 4 Spare Fuse

Figure 2-1.

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National Instruments Corporation 2-1 AT-MIO-16X User Manual

AT-MIO-16X with 50-Pin I/O Connector Parts Locator Diagram

Chapter 2 Configuration and Installation

1

234

1 Product Name, Assembly Number, and Revision Letter 2Fuse 3 U112 4 Spare Fuse

Figure 2-2. AT-MIO-16X with 68-Pin I/O Connector Parts Locator Diagram

Board Configuration

The AT-MIO-16X contain s one DIP switch to conf igure the base
address selection for the AT bus interface. The remaining resource
selections, such as DMA and interrupt channel selections, are
determined by programming the individual reg isters in the
AT-MIO-16X register set. The general location of the registers in the
I/O space of the PC is determined by the base address selection, whereas
the specific location of the registers within the register set is determined
by the AT-MIO-16X dec ode c irc uitry.

AT Bus Interface

Operation of the AT-MIO-16X multifunction I/O board is controlled
through accesses to registers within the board register set. Some of th e
registers in the register set retain data written to them to determine
board operation. Other registers in the register set contain impo rtant
status information necessary for proper sequencing of events. Still other
registers perform functions by accessing them either by reading from or
writing to their location. However, these registers do not retain
pertinent data when written to, nor do they provide pertinent status
information when read.

AT-MIO-16X User Manual 2-2

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National Instruments Corporation

The PC defines accesses to plug- in boa rds to be I/O mappe d acc esses
within the I/O space of the computer. Locations are either written to or
read from as bytes or words. Each register in the register set is mapped
to a certain offset from the base address selection of the board as read
or write, and as a word or byte location as defined by the decode
circuitry.

Base I/O Address Selection

The AT-MIO-16X is conf igur ed a t the f actor y to a ba se I /O addre ss
of 220 hex. This base address setting is suitable for most systems.
However, if your sy stem has othe r har dw are at this ba se I/O a ddre ss,
you must change either the AT-MIO-16X base address DIP switch or
the other hardware base address to avoid a conflict. Figure 2-3 shows a
graphical representation of the b ase add ress se lection D IP switc h, a nd
also shows how to reconfigure the selected base address.

Switch up for 1

Switch down for 0

Chapter 2 Configuration and Installation

U112

12345

O
N

O
F
F

A7

A9

A8

A6

A5

A. Switches Set to Base I/O Address of Hex 000

U112

12345

Switch up for 1

Switch down for 0

O
N

O
F
F

A9

A8

A7

A6

A5

B. Switches Set to Base I/O Address of Hex 220 (Factory Setting)

Figure 2-3.

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National Instruments Corporation 2-3 AT-MIO-16X User Manual

Example Base I/O Address Switch Settings

Chapter 2 Configuration and Installation

The base address DIP switch is arranged so that a logical 1 or true state
for the associated address selection bit is selected by pushing the toggle
switch up, or toward the top of the board. A lternate ly, a logical 0 or
false state is selected by pushing the toggle switch down, or toward the
bottom of the board. In Figur e 2-3B, A 9 is up (tr ue), A8 thro ugh A6
are low (false), and A5 is up (true). This repres ents a binary value of
10001XXXXX, or hex 220. The Xs indicate don’t care bits and are the
five least significant bits (LSBs) of the a ddre ss (A 4 throu gh A0 ) use d
by the AT-MIO-16X circuitry to decode the individual register
selections. The don’t care bits indicate the size of the register space. In
this case, the AT-MIO-16X u ses I/O a ddress he x 2 20 th rough h ex 23 F
in the factory-default setting.

Note: If you change the AT-MIO-16X base I/O addres s, yo u must make a

corresponding change to any so ftware pac kage s you use with the
AT-MIO-16X. Table 2-1 lists the default settings of other National
Instruments products for the PC. Table 2-2 lists the possible switch
settings, the corresponding base I/O address, and the base I/O address
space used for that setting. For more information about the I/O address
of your PC, refer to the technical reference manual for your computer.

Table 2-1. Default Settings of National Instruments Products for the PC

Board DMA

AT-A2150 None* None* 120 hex
AT-AO-6/10 Channel 5 Lines 11, 12 1C0 hex
AT-DIO-32F Channels 5, 6 Lines 11, 12 240 hex
AT-DSP2200 None* None* 120 hex
AT-GPIB Channel 5 Line 11 2C0 hex
AT-MIO-16 Channels 6, 7 Line 10 220 hex
AT-MIO-16D Channels 6, 7 Lines 5, 10 220 hex
AT-MIO-16F-5 Channels 6, 7 Line 10 220 hex
AT-MIO-16X None* None* 220 hex

AT-MIO-16X User Manual 2-4

Channel

Interrupt

Level

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National Instruments Corporation

Base I/O

Address

Chapter 2 Configuration and Installation

Table 2-1. Default Settings of National Instruments Products for the PC (Continued)

Board DMA

Channel

Interrupt

Level

Base I/O

Address

AT-MIO-64F-5 None* None* 220 hex
GPIB-PCII Channel 1 Line 7 2B8 hex
GPIB-PCIIA Channel 1 Line 7 02E1 hex
GPIB-PCIII Channel 1 Line 7 280 hex
Lab-PC Channel 3 Line 5 260 hex
PC-DIO-24 None Line 5 210 hex
PC-DIO-96 None Line 5 180 hex
PC-LPM-16 None Line 5 260 hex
PC-TIO-10 None Line 5 1A0 hex

* These settings are software configurable and are disabled a t sta rt up ti m e.

Table 2-2. Switch Settings with Corresponding Base I/O Address and

Base I/O Address Space

Switch Setting

A9 A8 A7 A6 A5

Base I/O

Address (hex)

Base I/O

Address Space

Used (hex)

0 0 X X X 000 - E00 Reserved
0 1 0 0 0 100 100 - 11F
0 1 0 0 1 120 120 - 13F
0 1 0 1 0 140 140 - 15F
0 1 0 1 1 160 160 - 17F
0 1 1 0 0 180 180 - 19F
0 1 1 0 1 1A0 1A0 - 1BF

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National Instruments Corporation 2-5 AT-MIO-16X User Manual

Chapter 2 Configuration and Installation

Table 2-2. Switch Settings with Corresponding Base I/O Address and

Base I/O Address Space (Continued)

Switch Setting

A9 A8 A7 A6 A5

Base I/O

Address (hex)

Base I/O

Address Space

Used (hex)

0 1 1 1 0 1C0 1C0 - 1DF
0 1 1 1 1 1E0 1E0 - 1FF
1 0 0 0 0 200 200 - 21F
1 0 0 0 1 220 220 - 23F
1 0 0 1 0 240 240 - 25F
1 0 0 1 1 260 260 - 27F
1 0 1 0 0 280 280 - 29F
1 0 1 0 1 2A0 2A0 - 2BF
1 0 1 1 0 2C0 2C0 - 2DF
1 0 1 1 1 2E0 2E0 - 2FF
1 1 0 0 0 300 300 - 31F
1 1 0 0 1 320 320 - 33F
1 1 0 1 0 340 340 - 35F
1 1 0 1 1 360 360 - 37F
1 1 1 0 0 380 380 - 39F
1 1 1 0 1 3A0 3A0 - 3BF
1 1 1 1 0 3C0 3C0 - 3DF
1 1 1 1 1 3E0 3E0 - 3FF

AT-MIO-16X User Manual 2-6

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National Instruments Corporation

Interrupt and DMA Channel Selection

The base I/O address selection is the only resource on the AT-MIO-16X
board that must be set manually before the board is placed into the PC.
The interrupt level and DMA channels used by the AT-MIO-16X are
selected via registers in the AT-MIO-16X register set. The
AT-MIO-16X powers up with all interrupt and DMA requests disabled.
To use the interrupt capability of the AT-MIO-16X, an interrupt level
must first be selected via register programming, then the specific
interrupt mode must be enabled. The same method holds for DMA
channel selection. To use the DMA capability of the board, one or two
DMA channels must be selected through the appropriate register, then
the specific DMA mode must be enabled. It is possible to have interrupt
and DMA resourc es con cur rently en ab led.

The interrupt lines supported by the AT-MIO-16X hardware are IRQ3,
IRQ4, IRQ5, IRQ7, IRQ10, IRQ11, IRQ12, and IRQ15. The DMA
channels supported are Channe ls 0 through 3, and Channe ls 5
through 7. If you use the AT-MIO-16X in an AT-ty pe compute r, you
should only use DMA Channels 5 through 7 beca use these are the only
16-bit channels available. If you use the board in an EISA computer, all
channels are capable of 16- bit transfers an d you can use them . The
AT-MIO-16X does not use and cannot be configured to use th e 8-b it
DMA Channels 0 throug h 3 o n the PC I /O chan ne l fo r 16-bit tra nsf ers.

Chapter 2 Configuration and Installation

Analog Input Configuration

The analog input section of the AT-MIO-16X is software configurable.
You can select different analog in put config urations by progr amming
the appropriate register in the AT-MIO-16X register set. The following
paragraphs describe in detail each of the analog input categories.

Input Mode

The AT-MIO-16X offer s th ree diff er ent inpu t m odesSE) inp ut,
referenced single-en de d (RSE ) in put, and diff eren tial (DI FF) input.
The single-ended input conf igura tions use u p to 16 cha nnels. T he
DIFF input configuration uses up to eight channels. Input modes are
programmed on a per chann el basis for multimode scanning. For
example, the circuitry can be conf igured to effectively sca n
12 channels, four diffe rentia lly c onfigur ed cha nne ls and ei ght
single-ended channels. The in put configura tions are de scribe d in
Table 2-3.

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National Instruments Corporation 2-7 AT-MIO-16X User Manual

Chapter 2 Configuration and Installation

Table 2-3.

Available Input Configurations for the AT-MIO-16X

Configuration Description

DIFF Differential configurationnput of the PGIA tied to

the multiplexer output of Channels 8 thro ugh 15.

RSE Referenced single-end ed configurationve ( –) input

of the PGIA referenced to analog ground.

NRSE Nonreferenced single-ended configurationative (–)

input of the PGIA tied to AI SENSE and not
connected to ground.

While reading the following paragraphs, you may find it helpful to refer
to the Analog Input Signal Connections section later in this chapter,
which contains diagrams showing the signal paths for the three
configurations.

DIFF Input (Eight Channels)

DIFF input means that each input signal has its own reference, an d the
difference bet ween each sign al and its re ference is me asured. The signa l
and its reference are assigned an input channel. This is the
recommended con figura tion. With this inpu t c onfigur ation , th e
AT-MIO-16X can monitor up to eigh t different ana log input signals.
This configuration is se lect ed v ia softwa re. See th e co nfig uration
memory register a nd T abl e 4-9 i n Cha pt er 4, Register Map and
Descriptions. The results of this configuration are as follows:

• One of Channels 0 thro ugh 7 is tied to the p ositive (+) inpu t of
the PGIA.

• One of Channe ls 8 thro ugh 15 is tied to the neg ative (–) inp ut o f
the PGIA.

• Multiplexer control is configured to control up to eight input
channels.

• AI SENSE may be driven by the board analog input ground or left
unconnected.

Considerations for using the DIFF input configuration are discussed in
the Signal Connections section later in this chapter. Figure 2-8 shows a
schematic diagram of this configuration.

AT-MIO-16X User Manual 2-8

©

National Instruments Corporation