National Instruments DAQCard-1200 Digital I/O Signal Connections

Chapter 3 Signal Connections

© National Instruments Corporation 3-15 DAQCard-1200 User Manual

Digital I/O Signal Connections

Caution The DAQCard-1200 DIO lines are not pulled up or pulled down. If you are using

these lines as digital outputs, add 10 k

Ω

ΩΩ

Ω

resistors to +5 V or DGND (depending on

your application) to the DIO line(s) you are using.

Pins 13 through 37 of the front connector are digital I/O signal pins.

DigitalI /O on the DAQCard-1200 uses the 82C55A integrated circuit.

The 82C55A is a general-purpose peripheral interface containing

24 programmable I/O pins. These pins represent the three 8-bit po rts

(PA,PB, and PC) of the 82C55A.

Pins 14 through 21 are connected to the digital lines PA<0..7> for

digital I/O port A. Pins 22 through 29 are connected to the digital lines

PB<0..7> for digital I/O port B. Pins 30 through 37 are connected to the

digital lines PC<0..7> for digital I/O port C. Pin 13, DGND, is the digital

ground pin for all three digital I/O ports. Refer to Appendix A,

Specifications, for signal voltage and current specifications.

!

Contents

Main Page Important Information Warranty Copyright Trademarks WARNING REGARDING USE OF NATIONAL INSTRUMENTS PRODUCTS Contents Chapter 4 Theory of Operation Page Tables About This Manual Organization of This Manual Conventions Used in This Manual National Instruments Documentation Related Documentation Introduction About the DAQCard-1200 What You Need to Get Started Software Programming Choices LabVIEW and LabWindows/CVI Application Software NI-DAQ Driver Software Register-Level Programming Optional Equipment Unpacking Installation and Configuration Installation Configuration Analog Input Configuration Analog Input Polarity Analog Input Mode RSE Input (Eight Channels, Default Setting) NRSE Input (Eight Channels) DIFF Input (Four Channels) Analog Output Configuration Analog Output Polarity Digital I/O Configuration Counter Configuration Signal Connections I/O Connector Figure 3-1. DAQCard-1200 I/O Connector Pin Assignments Signal Connection Descriptions Analog Input Signal Connections + Types of Signal Sources Floating Signal Sources Ground-Referenced Signal Sources Input Configurations Differential Connection Considerations (DIFF Configuration) Differential Connections for Grounded Signal Sources Figure 3-3. Differential Input Connections for Grounded Signal Sources Differential Connections for Floating Signal Sources Figure 3-4. Differential Input Connections for Floating Sources Single-Ended Connection Considerations Single-Ended Connections for Floating Signal Sources (RSE Configuration) Single-Ended Connections for Grounded Signal Sources (NRSE Configuration) Common-Mode Signal Rejection Considerations Analog Output Signal Connections Digital I/O Signal Connections Page Port C Pin Connections Timing Specifications Mode 1 Input Timing Mode 1 Output Timing Mode 2 Bidirectional Timing Page DAQ and General-Purpose Timing Signal Connections DAQ Timing Connections Page Page Page General-Purpose Timing Signal Connections Page Page Figure 3-18. Frequency Measurement Application Chapter 3 Signal Connections DAQCard-1200 User Manual 3-30 National Instruments Corporation Figure 3-19. General-Purpose Timing Signals The GATE and OUT signals in Figure3-19 are referenced to the rising edge of the CLK signal. Power Connections National Instruments Corporation 4-1 DAQCard-1200 User Manual Theory of Operation This chapter explains the operation of each functional unit of the DAQCard-1200. Figure 4-1. DAQCard-1200 Block Diagram Functional Overview The block diagram in Figure 4-1 shows a functional overview of the DAQCard-1200. PC Card I/O Channel Interface Circuitry Timing Chapter 4 Theory of Operation Figure 4-3. Timing Circuitry DAQCard-1200 User Manual 4-4 National Instruments Corporation Analog Input Analog Input Circuitry Page Data Acquisition Timing Data Acquisition Operation Continuous Data Acquisition Interval Data Acquisition Data Acquisition Rates Page Analog Output Analog Output Circuitry Power-On State DAC Timing Digital I/O Calibration Calibration at Higher Gains Calibration Equipment Requirements Using the Calibration Function Page A Specifications Analog Input Input Characteristics Transfer Characteristics Amplifier Characteristics Dynamic Characteristics Stability Analog Output Output Characteristics Transfer Characteristics Page Timing I/O Digital Trigger Bus Interface Power Requirement Physical Page B Differences among the Lab-PC+, the DAQPad-1200, and the DAQCard-1200 Page C Power-Management Modes Page D PC Card Questions and Answers Configuration Operation Resources Page Page E Technical Support Resources NI Web Support Online Problem-Solving and Diagnostic Resources Software-Related Resources Worldwide Support Glossary Numbers/Symbols A B C D E F G Page Page V Index Numbers A B C D E F G I L M N O R S T U V W