National Instruments AT-MIO-16D User manual

© Copyright 1992, 1995 National Instruments Corporation.
All Rights Reserved.
AT-MIO-16D
User Manual
Multifunction I/O Board for the PC AT
March 1995 Edition
Part Number 320489-01

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Limited Warranty
The AT-MIO-16D 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 Instruments software are warranted not to fail to execute programming
instructions, due to defects in materials and workmanship, for a period of 90 days from date of shipment, as
evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace software
media that do not execute programming 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 parts which are covered by warranty.
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© National Instruments Corporation v AT-MIO-16D User Manual
Preface
This manual describes the electrical and mechanical aspects of the AT-MIO-16D and contains
information concerning its operation and programming. The AT-MIO-16D, a member of the
National Instruments AT Series of expansion boards for the IBM PC AT and compatible
computers, combines the functionality of two popular National Instruments boards, the
AT-MIO-16 and the PC-DIO-24. The AT-MIO-16D contains two logical sections–the MIO-16
circuitry and the DIO-24 circuitry. The MIO-16 circuitry contains a 12-bit ADC with up to 16
analog inputs, two 12-bit DACs with voltage outputs, eight lines of transistor-transistor logic
(TTL) compatible digital I/O, and three 16-bit counter/timer channels for timing I/O. The DIO-
24 circuitry is a 24-bit parallel, digital I/O interface based on an 82C55A programmable
peripheral interface (PPI). If you require signal conditioning or additional analog inputs, you can
use the SCXI signal conditioning modules, the SCXI multiplexer products, or the AMUX-64T
multiplexer board.
Organization of This Manual
The AT-MIO-16D User Manual is organized as follows:
• Chapter 1, Introduction, describes the AT-MIO-16D; lists the contents of your AT-MIO-16D
kit, the optional software, and optional equipment; and explains how to unpack the
AT-MIO-16D.
• Chapter 2, Configuration and Installation, describes the AT-MIO-16D jumper configuration,
installation of the AT-MIO-16D board into the PC, signal connections to the AT-MIO-16D
board, cable wiring, and handshake timing diagrams for the DIO-24 circuitry of the
AT-MIO-16D.
• Chapter 3, Theory of Operation, contains a functional overview of the AT-MIO-16D and
explains the operation of each functional unit making up the AT-MIO-16D.
• Chapter 4, Programming, discusses the programming of the AT-MIO-16D. Included in this
chapter are the AT-MIO-16D register address map, a detailed register description, and a
functional programming description.
• Chapter 5, Calibration Procedures, discusses the calibration procedures for the
AT-MIO-16D analog input and analog output circuitry.
• Appendix A, Specifications, lists the specifications for the AT-MIO-16D.
• Appendix B, MIO-16 I/O Connector, describes the pinout and signal names for the MIO-16
50-pin I/O connector of the AT-MIO-16D.
• Appendix C, DIO-24 I/O Connector, describes the pinout and signal names for the DIO-24
50-pin I/O connector of the AT-MIO-16D.
• Appendix D, AT-MIO-16D I/O Connector, describes the pinout and signal names for the
AT-MIO-16D 100-pin I/O connector.

Preface
AT-MIO-16D User Manual vi © National Instruments Corporation
• Appendix E, AMD Am9513A Data Sheet, contains the manufacturer data sheet for the
Am9513A System Controller integrated circuit (Advanced Micro Devices, Inc.). This device
is used on the AT-MIO-16D.
• Appendix F, Oki MSM82C55A Data Sheet, contains the manufacturer data sheet for the
MSM82C55A CMOS Programmable Peripheral Interface (Oki Semiconductor). This device
is used on the AT-MIO-16D.
• Appendix G, Customer Communication, contains forms for you to complete to facilitate
communication with National Instruments concerning our products.
• The Index alphabetically lists topics covered in this manual, including the page where the
topic can be found.
Conventions Used in This Manual
The following conventions are used to distinguish elements of text throughout this manual:
italic Italic text denotes emphasis, a cross reference, or an introduction to a key
concept.
PC PC refers to the IBM PC AT and compatible computers.
Abbreviations
The following metric system prefixes are used with abbreviations for units of measure in this
manual:
Prefix Meaning Value
p- pico- 10-12
n- nano- 10-9
µ- micro- 10-6
m- milli- 10-3
k- kilo- 103
M- mega- 106
G- giga- 109
The following abbreviations are used in this manual:
A amperes
dB decibels
ft feet
hex hexadecimal
Hz hertz
kbytes 1,000 bytes
ksamples 1,000 samples
M megabytes of memory

Preface
© National Instruments Corporation vii AT-MIO-16D User Manual
Abbreviations (continued)
m meters
Ωohms
ppm parts per million
sec seconds
V volts
Vrms volts, root mean square
Acronyms
The following acronyms are used in this manual:
AC alternating current
A/D analog-to-digital
ADC A/D converter
D/A digital-to-analog
DAC D/A converter
DIP dual inline package
DMA direct memory access
FIFO first-in-first-out
I/O input/output
LS low-power Schottky
LSB least significant bit
MSB most significant bit
PPI programmable peripheral interface
RTSI Real-Time System Integration
SSR solid-state relays
TTL transistor-transistor logic
VDC volts direct current
Related Documentation
The following document contains information that you may find helpful as you read this manual:
•IBM Personal Computer AT Technical Reference manual
You may also want to consult the following Advanced Micro Devices manual if you plan to
program the Am9513A Counter/Timer used on the AT-MIO-16D:
•Am9513A/Am9513 System Timing Controller technical manual
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 Appendix G, Customer
Communication, at the end of this manual.

© National Instruments Corporation ix AT-MIO-16D User Manual
Contents
Chapter 1
Introduction..........................................................................................................................1-1
What Your Kit Should Contain......................................................................................1-3
Optional Software..........................................................................................................1-4
Optional Equipment.......................................................................................................1-5
Custom Cables...................................................................................................1-6
Unpacking......................................................................................................................1-7
Chapter 2
Configuration and Installation.......................................................................................2-1
Board Configuration ......................................................................................................2-1
AT Bus Interface............................................................................................................2-1
Base I/O Address Selection............................................................................................2-3
DMA Channel Selection................................................................................................2-5
Interrupt Selection..........................................................................................................2-7
DIO-24 Circuitry Interrupt Enable Settings.......................................................2-8
Analog I/O Jumper Settings...........................................................................................2-8
Analog Input Configuration...........................................................................................2-10
Input Mode.........................................................................................................2-10
DIFF Analog Input (Eight Channels, Factory Setting)..........................2-10
RSE Analog Input (16 Channels)...........................................................2-11
NRSE Analog Input (16 Channels)........................................................2-12
Analog Input Polarity and Range.......................................................................2-12
Considerations for Selecting Analog Input Ranges...............................2-14
Analog Output Configuration........................................................................................2-15
Analog Output Reference Selection...................................................................2-15
External Reference Selection.................................................................2-15
Internal Reference Selection (Factory Setting)......................................2-15
Analog Output Polarity Selection......................................................................2-16
Bipolar Output Selection (Factory Setting) ...........................................2-16
Straight Binary Mode.................................................................2-17
Two's Complement Mode (Factory Setting)..............................2-17
Unipolar Output Selection .....................................................................2-18
RTSI Bus Clock Selection.............................................................................................2-18
Hardware Installation.....................................................................................................2-20
Signal Connections ........................................................................................................2-20
AT-MIO-16D I/O Connector Pin Description...................................................2-21
MIO-16 I/O Connector Pin Description.............................................................2-22
MIO-16 Signal Connection Descriptions...........................................................2-23
Analog Input Signal Connections......................................................................2-25
Types of Signal Sources.....................................................................................2-26
Floating Signal Sources .........................................................................2-26
Ground-Referenced Signal Sources.......................................................2-27
Input Configurations..........................................................................................2-27
Differential Connection Considerations (DIFF Configuration).............2-27
Differential Connections for Grounded Signal Sources ........................2-28
Differential Connections for Floating Signal Sources...........................2-29
Single-Ended Connection Considerations .............................................2-30

Contents
AT-MIO-16D User Manual x © National Instruments Corporation
Single-Ended Connections for Floating Signal Sources (RSE
Configuration)........................................................................................2-30
Single-Ended Connections for Grounded Signal Sources (NRSE
Configuration)........................................................................................2-31
Common-Mode Signal Rejection Considerations..................................2-32
Analog Output Signal Connections....................................................................2-33
Digital I/O Signal Connections..........................................................................2-34
Power Connections ............................................................................................2-36
Timing Connections...........................................................................................2-36
Data Acquisition Timing Connections...................................................2-36
General-Purpose Timing Signal Connections........................................2-38
DIO-24 I/O Connector Pin Description.............................................................2-43
DIO-24 Signal Connection Descriptions...........................................................2-44
Power Connections ................................................................................2-44
Port C Pin Assignments.........................................................................2-44
Timing Specifications........................................................................................2-45
DIO-24 Mode 1 Input Timing................................................................2-47
DIO-24 Mode 1 Output Timing.............................................................2-48
DIO-24 Mode 2 Bidirectional Timing...................................................2-49
Cabling and Field Wiring...............................................................................................2-50
Field Wiring Considerations..............................................................................2-50
MIO-16 Cabling Considerations........................................................................2-50
DIO-24 Cabling Considerations.........................................................................2-51
Chapter 3
Theory of Operation..........................................................................................................3-1
MIO-16 Functional Overview........................................................................................3-1
PC AT I/O Channel Interface Circuitry.........................................................................3-2
Analog Input and Data Acquisition Circuitry................................................................3-4
Analog Input Circuitry.......................................................................................3-6
Analog Input Multiplexers.....................................................................3-6
Analog Input Mode Selection................................................................3-6
The Instrumentation Amplifier..............................................................3-6
Channel Selection Circuitry...................................................................3-6
A/D Converter........................................................................................3-7
ADC FIFO Buffer..................................................................................3-7
Data Acquisition Timing Circuitry....................................................................3-7
Single Conversions ................................................................................3-8
Sample-Interval Timer...........................................................................3-8
Sample Counter......................................................................................3-8
Single-Channel Data Acquisition...........................................................3-9
Multiple-Channel (Scanned) Data Acquisition......................................3-9
Data Acquisition Rates...........................................................................3-9
Analog Output Circuitry................................................................................................3-10
Analog Output Range.........................................................................................3-11
Analog Output Data Coding ..............................................................................3-11
MIO-16 Digital I/O Circuitry.........................................................................................3-11
Timing I/O Circuitry......................................................................................................3-13
RTSI Bus Interface Circuitry.........................................................................................3-15
DIO-24 Functional Overview........................................................................................3-17
DIO-24 Interrupt Control Circuitry................................................................................3-17
DIO-24 Circuitry I/O Connector....................................................................................3-18

Contents
© National Instruments Corporation xi AT-MIO-16D User Manual
82C55A Programmable Peripheral Interface.................................................................3-18
82C55A Modes of Operation.............................................................................3-18
Mode 0...................................................................................................3-18
Mode 1...................................................................................................3-19
Mode 2...................................................................................................3-19
Single Bit Set/Reset Feature ..................................................................3-19
Chapter 4
Programming........................................................................................................................4-1
Register Map..................................................................................................................4-1
Register Sizes.....................................................................................................4-2
Register Description...........................................................................................4-2
Register Description Format..................................................................4-3
Configuration and Status Register Group..........................................................4-3
Command Register 1..............................................................................4-4
Status Register........................................................................................4-6
Command Register 2..............................................................................4-9
The Event Strobe Register Group......................................................................4-11
Start Convert Register............................................................................4-12
Start DAQ Register................................................................................4-13
A/D Clear Register.................................................................................4-14
External Strobe Register........................................................................4-15
Analog Output Register Group..........................................................................4-16
DAC0 Register.......................................................................................4-17
DAC1 Register.......................................................................................4-18
INT2CLR Register.................................................................................4-19
Analog Input Register Group.............................................................................4-20
Mux-Counter Register............................................................................4-21
Mux-Gain Register.................................................................................4-22
A/D FIFO Register.................................................................................4-24
DMA TC INT Clear Register.................................................................4-25
Am9513A Counter/Timer Register Group ........................................................4-26
Am9513A Data Register........................................................................4-27
Am9513A Command Register...............................................................4-28
Am9513A Status Register......................................................................4-29
MIO-16 Digital I/O Register Group...................................................................4-30
MIO-16 Digital Input Register...............................................................4-31
MIO-16 Digital Output Register............................................................4-32
The RTSI Switch Register Group......................................................................4-33
RTSI Switch Shift Register....................................................................4-34
RTSI Switch Strobe Register.................................................................4-35
DIO-24 Register Group......................................................................................4-36
DIO-24 PORTA Register.......................................................................4-37
DIO-24 PORTB Register.......................................................................4-38
DIO-24 PORTC Register.......................................................................4-39
DIO-24 CNFG Register.........................................................................4-40
MIO-16 Programming Considerations...........................................................................4-41
Register Programming Considerations..............................................................4-41
Initializing the MIO-16 Circuitry of the AT-MIO-16D Board..........................4-41
Initializing the Am9513A......................................................................4-42
Initializing the Analog Output Circuitry................................................4-43

Contents
AT-MIO-16D User Manual xii © National Instruments Corporation
Programming the Analog Input Circuitry..........................................................4-43
A/D FIFO Output Binary Formats.........................................................4-44
Clearing the Analog Input Circuitry......................................................4-45
Programming Multiple A/D Conversions on a Single Input Channel...............4-46
External Timing Considerations for Multiple A/D Conversions.......................4-51
Pretriggering with the STOP TRIG Signal............................................4-51
Controlling Multiple A/D Conversions with the EXTCONV* Signal..4-55
Programming Multiple A/D Conversions with Channel Scanning....................4-57
Multiple A/D Conversions with Continuous Channel Scanning
(Round Robin)........................................................................................4-57
Multiple A/D Conversions with Interval Channel Scanning
(Pseudo-Simultaneous)..........................................................................4-62
External Timing Considerations for Scanned Data Acquisition............4-68
Resetting the Hardware after a Data Acquisition Operation..............................4-68
Resetting Counter 2................................................................................4-69
Resetting Counter 3................................................................................4-69
Resetting Counter 4................................................................................4-70
Resetting Counter 5................................................................................4-70
Programming the Analog Output Circuitry .......................................................4-71
Programming the MIO-16 Digital I/O Circuitry................................................4-72
Programming the Am9513A Counter/Timer.....................................................4-73
RTSI Bus Trigger Line Programming Considerations ......................................4-73
AT-MIO-16D RTSI Signal Connection Considerations........................4-74
Programming the RTSI Switch..............................................................4-75
Programming DMA Operations.........................................................................4-76
Interrupt Programming.......................................................................................4-77
DIO-24 Circuitry Programming Considerations............................................................4-78
DIO-24 Circuitry Register Descriptions............................................................4-78
82C55A Modes of Operation.............................................................................4-80
Mode 0–Basic I/O..................................................................................4-80
Mode 0 Programming Example.................................................4-81
Mode 1–Strobed Input ...........................................................................4-82
Mode 1 Input Programming Example........................................4-84
Mode 1–Strobed Output.........................................................................4-84
Mode 1 Output Programming Example.....................................4-86
Mode 2–Bidirectional Bus.....................................................................4-87
Mode 2 Programming Example.................................................4-88
Single Bit Set/Reset Feature ..................................................................4-89
Interrupt Programming Examples......................................................................4-89
DIO-24 Interrupt Handling............................................................................................4-90
Chapter 5
Calibration Procedures.....................................................................................................5-1
Calibration Equipment Requirements............................................................................5-1
Calibration Trimpots......................................................................................................5-2
Analog Input Calibration ...............................................................................................5-3
Board Configuration ..........................................................................................5-4
Bipolar Input Calibration Procedure..................................................................5-4
Unipolar Input Calibration Procedure................................................................5-5
Analog Output Calibration.............................................................................................5-6
Board Configuration ..........................................................................................5-7
Bipolar Output Calibration Procedure...............................................................5-7
Unipolar Output Calibration Procedure.............................................................5-8

Contents
© National Instruments Corporation xiii AT-MIO-16D User Manual
Appendix A
Specifications........................................................................................................................A-1
MIO-16 Circuitry Specifications ...................................................................................A-1
Analog Input ......................................................................................................A-1
Explanation of Analog Input Specifications..........................................A-2
Analog Data Acquisition Rates..........................................................................A-3
Single-Channel Acquisition Rates.........................................................A-3
Multiple-Channel Scanning Acquisition Rates......................................A-3
Analog Output....................................................................................................A-4
Explanation of Analog Output Specifications .......................................A-4
Digital I/O (MIO-16 I/O Connector only).........................................................A-5
Timing I/O..........................................................................................................A-5
DIO-24 Circuitry Specifications....................................................................................A-5
I/O Signals Rating..............................................................................................A-5
Input Signal Specifications................................................................................A-5
Output Signal Specifications..............................................................................A-6
Transfer Rates................................................................................................................A-6
Power Requirement (from PC AT I/O Channel) ...........................................................A-6
Physical..........................................................................................................................A-6
Operating Environment..................................................................................................A-6
Storage Environment......................................................................................................A-6
Appendix B
MIO-16 I/O Connector......................................................................................................B-1
MIO-16 Signal Connection Descriptions.......................................................................B-2
Appendix C
DIO-24 I/O Connector.......................................................................................................C-1
DIO-24 Signal Connection Descriptions.......................................................................C-2
Appendix D
AT-MIO-16D I/O Connector..........................................................................................D-1
Appendix E
AMD Am9513A Data Sheet.............................................................................................E-1
Appendix F
Oki MSM82C55A Data Sheet.........................................................................................F-1
Appendix G
Customer Communication...............................................................................................G-1
Index..................................................................................................................................Index-1

Contents
AT-MIO-16D User Manual xiv © National Instruments Corporation
Figures
Figure 1-1. AT-MIO-16D Interface Board..........................................................................1-2
Figure 1-2. AT-MIO-16D Cable Assembly........................................................................1-6
Figure 2-1. Parts Locator Diagram......................................................................................2-2
Figure 2-2. Example Base I/O Address Switch Settings.....................................................2-4
Figure 2-3. DMA Jumper Settings for DMA Channels 6 and 7 (Factory Setting)..............2-6
Figure 2-4. DMA Jumper Settings for DMA Channel 6 Only............................................2-6
Figure 2-5. DMA Jumper Settings for Disabling DMA Transfers......................................2-7
Figure 2-6. Factory Interrupt Jumper Settings IRQ5 (DIO-24) and IRQ10 (MIO-16).......2-7
Figure 2-7. Interrupt Jumper Setting for Disabling Interrupts ............................................2-8
Figure 2-8. Jumper Settings–PC6, PC4, PC2, and N/C.......................................................2-8
Figure 2-9. DIFF Analog Input Configuration (Factory Setting)........................................2-11
Figure 2-10. RSE Analog Input Configuration.....................................................................2-11
Figure 2-11. NRSE Analog Input Configuration ..................................................................2-12
Figure 2-12. 0 to +10 V Input Configuration........................................................................2-13
Figure 2-13. -5 to +5 V Input Configuration.........................................................................2-13
Figure 2-14. Factory -10 to +10 V Analog Input Configuration...........................................2-13
Figure 2-15. External Reference Configuration....................................................................2-15
Figure 2-16. Factory Internal Reference Configuration........................................................2-16
Figure 2-17. Factory Bipolar Output Configuration..............................................................2-16
Figure 2-18. Straight Binary Mode .......................................................................................2-17
Figure 2-19. Two's Complement Mode (Factory Setting).....................................................2-17
Figure 2-20. Unipolar Output Configuration.........................................................................2-18
Figure 2-21. Disconnect from RTSI Bus Clock; Use Onboard Oscillator
(Factory Setting)...............................................................................................2-19
Figure 2-22. Receive RTSI Bus Clock Signal.......................................................................2-19
Figure 2-23. Drive RTSI Bus Clock Signal with Onboard Oscillator...................................2-20
Figure 2-24. AT-MIO-16D I/O Connector Pin Assignments................................................2-21
Figure 2-25. MIO-16 I/O Connector Pin Assignments.........................................................2-22
Figure 2-26. AT-MIO-16D Instrumentation Amplifier.........................................................2-26
Figure 2-27. Differential Input Connections for Grounded Signal Sources..........................2-28
Figure 2-28. Differential Input Connections for Floating Sources........................................2-29
Figure 2-29. Single-Ended Input Connections for Floating Signal Sources.........................2-31
Figure 2-30. Single-Ended Input Connections for Grounded Signal Sources.......................2-32
Figure 2-31. Analog Output Connections .............................................................................2-34
Figure 2-32. Digital I/O Connections....................................................................................2-35
Figure 2-33. EXTSTROBE* Signal Timing.........................................................................2-36
Figure 2-34. EXTCONV* Signal Timing.............................................................................2-37
Figure 2-35. START TRIG* Signal Timing.........................................................................2-38
Figure 2-36. STOP TRIG Signal Timing..............................................................................2-38
Figure 2-37. Event-Counting Application with External Switch Gating..............................2-39
Figure 2-38. Frequency Measurement Application...............................................................2-40
Figure 2-39. General-Purpose Timing Signals......................................................................2-41
Figure 2-40. DIO-24 I/O Connector Pin Assignments..........................................................2-43
Figure 3-1. AT-MIO-16D MIO-16 Circuitry Block Diagram.............................................3-1
Figure 3-2. PC AT 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. Analog Output Circuitry Block Diagram .........................................................3-10
Figure 3-5. Digital I/O Circuitry Block Diagram................................................................3-12
Figure 3-6. Timing I/O Circuitry Block Diagram...............................................................3-13

Contents
© National Instruments Corporation xv AT-MIO-16D User Manual
Figure 3-7. Counter Block Diagram....................................................................................3-14
Figure 3-8. RTSI Bus Interface Circuitry Block Diagram..................................................3-16
Figure 3-9. AT-MIO-16D DIO-24 Block Diagram.............................................................3-17
Figure 4-1. RTSI Switch Control Pattern............................................................................4-75
Figure 4-2. Control-Word Formats......................................................................................4-79
Figure 5-1. Calibration Trimpot Location Diagram............................................................5-2
Figure B-1. AT-MIO-16D MIO-16 I/O Connector..............................................................B-1
Figure C-1. AT-MIO-16D DIO-24 I/O Connector..............................................................C-1
Figure D-1. AT-MIO-16D I/O Connector............................................................................D-1
Tables
Table 2-1. AT Bus Interface Factory Settings ...................................................................2-1
Table 2-2. Default Settings of Other National Instruments Products for the PC...............2-3
Table 2-3. Switch Settings with Corresponding Base I/O Address and Base I/O
Address Space...................................................................................................2-5
Table 2-4. DMA Channels for the AT-MIO-16D..............................................................2-6
Table 2-5. Analog I/O Jumper Settings..............................................................................2-9
Table 2-6. Input Configurations Available for the AT-MIO-16D.....................................2-10
Table 2-7. Configurations for Input Range and Input Polarity..........................................2-13
Table 2-8. Actual Range and Measurement Precision Versus Input Range Selection
and Gain............................................................................................................2-14
Table 2-9. Configurations for RTSI Bus Clock Selection.................................................2-19
Table 2-10. Recommended Input Configurations for Ground-Referenced and
Floating Signal Sources....................................................................................2-27
Table 2-11. Port C Signal Assignments...............................................................................2-45
Table 3-1. AT-MIO-16D Maximum Recommended Data Acquisition Rates...................3-10
Table 4-1. AT-MIO-16D Register Map.............................................................................4-1
Table 4-2. Straight Binary Mode A/D Conversion Values................................................4-45
Table 4-3. Two's Complement Mode A/D Conversion Values.........................................4-45
Table 4-4. Multiple-Channel Data Acquisition Rates........................................................4-68
Table 4-5. Analog Output Voltage Versus Digital Code (Unipolar Mode).......................4-71
Table 4-6. Analog Output Voltage Versus Digital Code (Bipolar Mode).........................4-72
Table 4-7. RTSI Switch Signal Connections.....................................................................4-74
Table 4-8. Port C Set/Reset Control Words.......................................................................4-80
Table 4-9. Mode 0 I/O Configurations...............................................................................4-81
Table 4-10. DIO-24 Interrupt Enable Signals for All Mode Combinations ........................4-91

© National Instruments Corporation 1-1 AT-MIO-16D User Manual
Chapter 1
Introduction
This chapter describes the AT-MIO-16D; lists the contents of your AT-MIO-16D kit, the
optional software, and optional equipment; and explains how to unpack the AT-MIO-16D.
The AT-MIO-16D combines the functionality of two popular National Instruments boards, the
AT-MIO-16 and the PC-DIO-24. The AT-MIO-16D contains two logical sections–the MIO-16
circuitry and the DIO-24 circuitry. Henceforth, we will refer to the entire board as the
AT-MIO-16D, and to a particular logical part of the board as either the MIO-16 or DIO-24
circuitry. The MIO-16 circuitry contains a 12-bit ADC with up to 16 analog inputs, two 12-bit
DACs with voltage outputs, eight lines of transistor-transistor logic (TTL) compatible digital I/O,
and three 16-bit counter/timer channels for timing I/O. The DIO-24 circuitry is a 24-bit parallel,
digital I/O interface based on an 82C55A programmable peripheral interface (PPI).
The MIO-16 circuitry of the AT-MIO-16D is a high-performance multifunction analog, digital,
and timing I/O circuit for the PC. The AT-MIO-16D has a fast 12-bit ADC, 16 single-ended or
eight differential channels (expandable with SCXI and the AMUX-64T), and programmable
gains of 1, 10, 100, and 500 or 1, 2, 4, and 8. The AT-MIO-16D has a 9-µsec converter,
guaranteed transfer rates of up to 100 ksamples/sec, and a 512-word A/D FIFO buffer to obtain
the highest possible data acquisition rate. The AT-MIO-16D has internal or external A/D timing,
two double-buffered multiplying 12-bit DACs, unipolar or bipolar voltage output, and an
onboard DAC reference voltage of 10 V. The AT-MIO-16D also has onboard timers for
waveform generation, eight digital I/O lines that can sink up to 24 mA of current, and three
independent 16-bit counter/timers for frequency counting, event counting, and pulse output
applications. The AT-MIO-16D has timer-generated interrupts, a high-performance RTSI bus
interface with four triggers for system-level timing, and full PC AT I/O channel DMA capability.
The DIO-24 circuitry of the AT-MIO-16D is a 24-bit parallel, digital I/O interface for the PC.
An 82C55A PPI controls the 24 bits of digital I/O. The 82C55A is very flexible and powerful
when interfacing with peripheral equipment, can operate in either a unidirectional or
bidirectional mode, and can generate interrupt request outputs. You can program the 82C55A
for almost any 8-bit or 16-bit digital I/O application. The 100-pin connector of the AT-MIO-
16D breaks out into two standard 50-pin female connectors via a cable assembly. The pin
assignments for these connectors are compatible with standard 24-channel digital I/O
applications.
Figure 1-1 shows the AT-MIO-16D interface board.

Chapter 1 Introduction
© National Instruments Corporation 1-3 AT-MIO-16D User Manual
With the AT-MIO-16D, the PC can serve as a digital I/O system controller for laboratory testing,
production testing, and industrial process monitoring and control.
The AT-MIO-16D is interfaced to the National Instruments RTSI bus. With this bus, National
Instruments AT Series boards can send timing signals to each other. The AT-MIO-16D can send
signals from the onboard counter/timer to another board, or another board can control single and
multiple A/D conversions on the AT-MIO-16D.
The AT-MIO-16D is available in two gain ranges. The AT-MIO-16DL-9 has
software-programmable gain settings of 1, 10, 100, and 500 for low-level analog input signals.
The AT-MIO-16DH-9 has software-programmable gain settings of 1, 2, 4, and 8 for high-level
analog input signals. The AT-MIO-16D contains an ADC with a 9-µsec conversion time, and is
capable of data acquisition rates of up to 100 kbytes/sec.
Detailed specifications for the AT-MIO-16D are listed in Appendix A, Specifications.
What Your Kit Should Contain
Each version of the AT-MIO-16D board has a different part number and kit part number, listed
as follows.
Kit Name Kit Part Number Kit Component Board Part
Number
AT-MIO-16DL-9 776646-01 AT-MIO-16DL-9 board 181965-01
AT-MIO-16DH-9 776646-11 AT-MIO-16DH-9 board 181965-11
The board part number is printed on your board along the top edge on the component side. You
can identify which version of the AT-MIO-16D board you have by looking up the part number in
the preceding table.
In addition to the board, each version of the AT-MIO-16D kit contains the following
components.
Kit Component Part Number
AT-MIO-16D User Manual
NI-DAQ software for DOS/Windows/LabWindows, with manuals
NI-DAQ Software Reference Manual for DOS/Windows/LabWindows
NI-DAQ Function Reference Manual for DOS/Windows/LabWindows
320489-01
776250-01
320498-01
320499-01
If your kit is missing any of the components or if you received the wrong version, contact
National Instruments.

Introduction Chapter 1
AT-MIO-16D User Manual 1-4 © National Instruments Corporation
Your AT-MIO-16D is shipped with the NI-DAQ software for DOS/Windows/LabWindows.
NI-DAQ has a library of functions that can be called from your application programming
environment. These functions include routines for analog input (A/D conversion), buffered data
acquisition (high-speed A/D conversion), analog output (D/A conversion), waveform generation,
digital I/O, counter/timer, SCXI, RTSI, and self-calibration. NI-DAQ maintains a consistent
software interface among its different versions so you can switch between platforms with
minimal modifications to your code. NI-DAQ comes with language interfaces for Professional
BASIC, Turbo Pascal, Turbo C, Turbo C++, Borland C++, and Microsoft C for DOS; and Visual
Basic, Turbo Pascal, Microsoft C with SDK, and Borland C++ for Windows. NI-DAQ software
is on high-density 5.25 in. and 3.5 in. diskettes.
Optional Software
This manual contains complete instructions for directly programming the AT-MIO-16D.
Normally, however, you should not need to read the low-level programming details in the user
manual because the NI-DAQ software package for controlling the AT-MIO-16D is included with
the board. Using NI-DAQ is quicker and easier than and as flexible as using the low-level
programming described in Chapter 4, Programming.
You can use the AT-MIO-16D with LabVIEW for Windows or LabWindows for DOS.
LabVIEW and LabWindows are innovative program development software packages for data
acquisistion and control applications. LabVIEW uses graphical programming, whereas
LabWindows enhances Microsoft C and QuickBASIC. Both packages include extensive
libraries for data acquisition, instrument control, data analysis, and graphical data presentation.
Part numbers for these software packages are listed in the following table.
Software Part Number
LabVIEW for Windows
LabWindows
Standard package
Advanced Analysis Library
Standard package with the Advanced Analysis
Library
776670-01
776473-01
776474-01
776475-01

Chapter 1 Introduction
© National Instruments Corporation 1-5 AT-MIO-16D User Manual
Optional Equipment
Equipment Part Number
CB-100 I/O connector block
0.5-m cable
1.0-m cable
Type NB5 100-conductor ribbon cable
0.5-m cable
1.0-m cable
SCXI signal conditioning modules
SCXI-1100 32-channel differential multiplexer/amplifier
SCXI-1120 8-channel isolated analog input
SCXI-1121 4-channel isolated transducer amplifier with excitation
SCXI-1140 8-channel simultaneously sampling differential amplifier
SCXI-1180 feedthrough panel
SCXI-1181 breadboard
AMUX-64T analog multiplexer board without cable
with 0.2-m ribbon cable
with 0.5-m ribbon cable
with 1.0-m ribbon cable
with 2.0-m ribbon cable
AT Series RTSI bus cables for
2 boards
3 boards
4 boards
5 boards
Cable adapter board for signal conditioning
SC-2050 without cable
SC-2051 without cable
SC-2060 optically isolated digital input board with conductor cable 0.2 m
0.4 m
SC-2061 optically isolated digital output board
with 26-conductor cable 0.2 m
0.4 m
SC-2062 electromechanical relay digital control board
with 26-conductor cable 0.2 m
0.4 m
General-purpose termination breadboard
SC-2070 without cable
SC-2072 without cable
SC-2072D without cable
BNC-2080 BNC adapter board without cable
Digital signal conditioning modules
SSR Series mounting rack and 1.0 m cable
24-channel without cable
16-channel without cable
8-channel without cable
8-channel with SC-205X cable
776455-01
776455-02
181304-05
181304-10
776572-00
776572-20
776572-21
776572-40
776572-80
776572-81
776366-90
776366-02
776366-05
776366-10
776366-20
776249-02
776249-03
776249-04
776249-05
776335-90
776335-91
776336-00
776336-10
776336-01
776336-11
776336-02
776336-12
776358-90
776358-92
776358-192
776579-90
776290-924
776290-916
776290-908
776290-18

Introduction Chapter 1
AT-MIO-16D User Manual 1-6 © National Instruments Corporation
Custom Cables
The AT-MIO-16D I/O connector is a 100-pin male ribbon cable header. The manufacturer part
number National Instruments uses for this header is as follows:
• Robinson Nugent (part number P50E-100P1-SR1-TG)
The mating connector for the board is a 100-position, polarized, ribbon socket connector. This
connector breaks out into two 50-pin female connectors with 50-conductor ribbon cables via a
cable assembly. National Instruments uses a keyed connector to prevent inadvertent upside-
down connection to the board. The recommended manufacturer part number for this mating
connector is as follows:
• Robinson Nugent (part number P50E-100S-TG)
Figure 1-2 shows the AT-MIO-16D cable assembly.
MIO-16 50-pin I/O
Connector
DIO-24 50-pin I/O
Connector
AT-MIO-16D 100-pin
I/O Connector
AT-MIO-16D Board
Figure 1-2. AT-MIO-16D Cable Assembly
Recommended manufacturer part numbers for standard ribbon cable (50-conductor, 28 AWG,
stranded) that can be used with the mating connector are as follows:
• Electronic Products Division/3M (part number 3365/50)
• T&B/Ansley Corporation (part number 171-50)
Recommended manufacturer part numbers for the 50-pin edge connector for connecting to a
module rack with an edge connector are as follows:
• Electronic Products Division/3M (part number 3415-0001)
• T&B Ansley Corporation (part number 609-5015M)