National Instruments PC-LPM-16/PnP Programming Considerations

Appendix D Register-Level Programming

PC-LPM-16/PnP User Manual D-26

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National Instruments Corporation

Programming Considerations

Following are programming instructions for operating the circuitry on

the PC-LPM-16/PnP. To program the PC-LPM-16/PnP, you must write

to and read from the various registers on the board. The following

programming instructions are language-independent; that is, they tell

you to write a value to a given register, to set or clear a bit in a given

register, or to detect whether a given bit is set or cleared without

presenting the actual code.

Register Programming Considerations

The PC-LPM-16/PnP can only be used for 8-bit I/O transfers, so all the

I/O read-and-write operations are 8-bit operations.

Several write-only registers on the PC-LPM-16/PnP contain bits that

control several independent pieces of the onboard circuitry. In the set or

clear instructions provided, you should set or clear specific register bits

without changing the current state of the remaining bits in the register.

However, writing to these registers affects all register bits

simultaneously. You cannot read these registers to determine which bits

have been set or cleared in the past; therefore, you should maintain a

software copy of the write-only registers. You can then read this

software copy to determine the status of the write-only registers. To

change the state of a single bit without disturbing the remaining bits, set

or clear the bit in the software copy and then write the software copy to

the register.

Initializing the PC-LPM-16/PnP

You must initialize the PC-LPM-16/PnP hardware for the circuitry to

operate properly. To initialize the PC-LPM-16/PnP hardware, complete

the following steps:

1. Write 00 (hex) to the Command Register 2.

2. Write 80 (hex) to the Command Register 1.

3. Write 34 (hex) to the Counter Mode Register.

4. Write 00 (hex) to the Timer Interrupt Clear Register.

5. Write 00 (hex) to the A/D Clear Register.

6. Read from A/D FIFO High-Byte and Low-Byte Registers and

ignore the data.

a.Book : l.Appendix D Page 26 Wednesday, November 20, 1996 6:36 PM

Contents

Main Page Important Information WARNING REGARDING MEDICAL AND CLINICAL USE OF NATIONAL INSTRUMENTS PRODUCTS Trademarks Copyright Page Page Glossary Index Figures Tables About This Manual Organization of This Manual Conventions Used in This Manual National Instruments Documentation Related Documentation Customer Communication Introduction About the PC-LPM-16/PnP What You Need to Get Started LabVIEW and LabWindows/CVI Application Software Software Programming Choices NI-DAQ Driver Software Register-Level Programming Optional Equipment Custom Cables Unpacking Installation and Configuration Hardware Installation Software Installation Plug and Play Board Configuration Base I/O Address and Interrupt Selection Non-Plug and Play Theory of Operation Functional Overview Chapter 3 Theory of Operation Figure 3-1. PC-LPM-16PnP Block Diagram PC I/O Channel Interface Circuitry Analog Input and Data Acquisition Circuitry Analog Input Circuitry Data Acquisition Timing Circuitry Single-Channel Data Acquisition Data Acquisition Rates Multichannel Scanning Data Acquisition Chapter 3 Theory of Operation PC-LPM-16/PnP User Manual 3-8 Digital I/O Circuitry Digital I/O Circuitry Block Diagram Figure 3-4. Timing I/O Circuitry Page Signal Connections I/O Connector Chapter 4 Signal Connections Figure 4-1. PC-LPM-16PnP I/O Connector Pin Assignments Signal Connection Descriptions Page Analog Input Signal Connections Connections for Signal Sources Digital I/O Signal Connections Power Connections Power Rating Data Acquisition Timing Connections Timing Connections General-Purpose Timing Signal Connections and General-Purpose Counter Timing Signals Page Page Page Specifications A Transfer Characteristics PC-LPM-16PnP Board Amplifier Characteristics Digital I/O Stability Dynamic Characteristics Timing I/O Bus Interface Explanation of Analog Input Specifications Environment Physical Page Page B MSM82C53 Data Sheet Page Page Page Page Page Page Page Page Page Page Page Using Your PC-LPM-16 (Non-PnP) Board C the PC-LPM-16 Differences between the PC-LPM-16PnP and Page Page Configuration and Installation of the Board Configuration PC-LPM-16 (non-PnP) Page Base I/O Address Selection Page Page Interrupt Selection Analog Input Jumper Settings 5 V) Bipolar Input Selection 1 ( Bipolar Input Selection 2 ( Unipolar Input Selection 1 (0 to 10 V) Select the bipolar ( 2.5 V) 2.5 V) input configuration by setting jumpers W1 and W2 as shown in Figure C-6. Unipolar Input Selection 2 (0 to 5 V) Installation Register-Level Programming D Register Map Base Address Register Size Register Descriptions Register Description Format Configuration and Status Register Group Page Page Page Command Register 2 Command Register 2 Command Register 3 Status Register 1 Status Register 1 Page Status Register 2 Analog Input Register Group A/D FIFO Low-Byte Register and A/D FIFO High-Byte Register A/D FIFO Low-Byte Register and A/D FIFO High-Byte Register A/D Clear Register Counter/Timer (MSM82C53) Register Group Counter 0 Data Register Counter 1 Data Register Counter 2 Data Register Page Page Page Timer Interrupt Clear Register Digital I/O Register Group Digital Output Register Digital Input Register Programming Considerations Register Programming Considerations Initializing the PC-LPM-16/PnP Programming the A/D Calibration Programming the Analog Input Circuitry Analog Input Circuitry Programming Sequence A/D FIFO Output Binary Modes Clearing the Analog Input Circuitry Programming Multiple A/D Conversions on a Single Input Channel Using Counter 0 Page Page Programming Multiple A/D Conversions Using External Timing Programming Multiple A/D Conversions with Channel Scanning A/D Interrupt Programming Programming the Digital I/O Circuitry Programming the MSM82C53 Counter/Timer Customer Communication FTP Support Electronic Services E Bulletin Board Support Telephone and Fax Support Telephone Fax Fax-on-Demand Support E-Mail Support (currently U.S. only) Technical Support Form PC-LPM-16/PnP Hardware and Software Configuration Form Other Products National Instruments Products Documentation Comment Form Glossary Symbols A C B Page Page T V A Numbers Index B C D E I H F G J P N M O R S T U