User manual

Introduction to NI-DAQ

This chapter describes how to set up your DAQ system and configure your

DAQ devices.

About the NI-DAQ Software for PC Compatibles

Thank you for buying a National Instruments DAQ device, which includes

NI-DAQ software for PC compatibles. NI-DAQ is a set of functions that

control all of the National Instruments plug-in DAQ devices for analog I/O,

digital I/O, timing I/O, SCXI signal conditioning, and RTSI multiboard

synchronization.

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. Examples of high-level functions are streaming data to

disk or acquiring a certain number of data points. Examples of low-level

functions are writing directly to the DAQ device registers or calibrating

the analog inputs. NI-DAQ does not sacrifice the performance of

National Instruments DAQ devices because it lets multiple devices

operate at their peak performance.

NI-DAQ includes a Buffer and Data Manager that uses sophisticated

techniques for handling and managing data acquisition buffers so that you

can acquire and process data simultaneously. NI-DAQ can transfer data

using DMA, interrupts, or software polling. NI-DAQ can use DMA to

transfer data into memory above 16 MB even on ISA bus computers.

With the NI-DAQ Resource Manager, you can use several functions

and several devices simultaneously. The Resource Manager prevents

multiboard contention over DMA channels, interrupt levels, and

RTSI channels.