National Instruments 320682C Chapter 10 Easy I/O for DAQ Library

Chapter 10Easy I/O for DAQ Library

This chapter describes the functions in the Easy I/O for DAQ Library. The Easy I/O for DAQ

Library Function Overview section contains general information about the functions, and

guidelines and restrictions you should know when using the Easy I/O for DAQ Library. The Easy

I/O for DAQ Library Function Reference section contains an alphabetical list of function

descriptions.

The functions in the Easy I/O for DAQ Library make it easier to write simple DAQ programs

than if you use the Data Acquisition Library.

This library implements a subset of the functionality of the Data Acquisition Library, but it does

not use the same functions as the Data Acquisition Library. Read the advantages and limitations

listed here to see if the Easy I/O for DAQ Library is appropriate for your application.

You must have NI-DAQ for PC Compatibles installed to use the Easy I/O for DAQ library. The

Easy I/O for DAQ library has been tested using version 4.6.1 and later of NI-DAQ. It has not

been tested using previous versions of NI-DAQ.

The sample programs for the Easy I/O for DAQ library are located in the

cvi\samples\easyio directory. These sample programs are discussed in the EASYIO

section of cvi\samples.doc.

Note: It is recommended that you do not mix calls to the Data Acquisition Library with

similar types of calls to the Easy I/O for DAQ Library in the same application. For

example, do not mix analog input calls to the Data Acquisition Library with analog

input calls to the Easy I/O for DAQ Library in the same program.

If you want to scan multiple analog input channels on an MIO board using the Data Acquisition

Library, you have to programmatically build a channel list and a gain list before calling

SCAN_Op.

The Easy I/O for DAQ functions accept a channel string and upper and lower input limit

parameters so that you can easily perform a scan in one step.

In the Data Acquisition Library you may have to use Lab_ISCAN_Op, or SCAN_Op, or

MDAQ_Start depending on which DAQ device you are using. Also, if you are using SCXI,

there are a number of SCXI specific functions that must be called prior to actually acquiring data.