User manual

Chapter 3 Software Overview

NI-DAQ User Manual for PC Compatibles 3-28 ni.com

Asynchronous start functions include

DAQ_Start

SCAN_Start

,and

Lab_ISCAN_Start

. Figures 3-6 and 3-7 show how the start calls make

up building block 2 for different devices.

Figure 3-6. Buffered Data Acquisition Application Building Block 2, Start,

for the MIO, AI, and DSA Devices

For DSA devices, substitute

DAQ_Set_Clock

for

DAQ_Rate

in Figure 3-6.

DAQ_Rate

will not produce the correct clock settings for DSA devices.

If your device works with multirate scanning, you can use

SCAN_Sequence_Setup

instead of

SCAN_Setup

in building block 2.

DAQ_Rate

Convert sampling rate to

sample timebase and

sample interval.

SCAN_Setup

Initiate single-channel

data acquisition.

SCAN_Start

DAQ_Start

Initiate multiple-channel

data acquisition.

Yes

Sample multiple

channels?

Select channels and

their gain for

multiple-channel scanning.