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The program will then collect one sample of channels 0 through 7 using the VBdaqAdcRdScan function.

ret& = VBdaqAdcRdScan&(handle&,0, 7, buf%(), DgainX1&,

DafAnalog&+DafUnipolar&)

Print “Results of AdcRdscan:”

For x& = 0 To 7

Print Format$“& # & ####”; “Channel:”; buf%(x); “Data:”; buf%(x)

Next x&: Print

Counted Acquisitions Using Linear Buffers

This section sets up an acquisition that

collects post-trigger A/D scans. This

particular example demonstrates the setting

up and collection of a fixed-length A/D

acquisition in a linear buffer.

First, the acquisition is configured by

setting up the channel scan group

configuration, the acquisition frequency,

the acquisition trigger and the acquisition

mode. When configured, the acquisition is

then armed by calling the

daqAdcArm

function.

At this point, the Daq device trigger is

armed and A/D acquisition will begin upon

trigger detection. If the trigger source has

been configured to be

DatsImmediate&,

A/D data collection will begin

immediately.

This example will retrieve 10 samples from

channels 0 through 7, triggered

immediately with a 1000 Hz sampling

frequency and unity gain. Functions used

include:

• VBdaqAdcSetMux&(handle&, startChan&, endChan&, gain&, flags&)

• VBdaqAdcSetFreq&(handle&,freq!)

• VBdaqAdcSetTrig&(handle&, triggerSource&, rising&, level%,

hysteresis%,channel&)

• VBdaqAdcSetAcq&(handle&,mode&,preTrigCount&,postTrigCount&)

• VBdaqAdcTransferSetBuffer&(handle&,buf%(), scanCount&, transferMask&)

• VBdaqAdcTransferStart&(handle&)

• VBdaqAdcWaitForEvent&(handle&,daqEvent&)

This program will initialize the Daq device hardware, then take readings from the analog input channels in

the base unit (not the expansion cards). The functions used in this program are of a lower level than those

used in the previous section and provide more flexibility.

Dim buf%(80), handle&, ret&, flags&

The following function defines the channel scan group. The function specifies a channel scan group from

channel 0 through 7 with all channels being analog unipolar input channels with a gain of ×1. Specifying

this configuration uses

DgainX1 in the gain parameter and the DafAnalog and the DafUnipolar values

in the

flags parameter. The flags parameter is a bit-mask field in which each bit specifies the

characteristics of the specified channel(s). In this case, the

DafAnalog and the DafUnipolar values are

added together to form the appropriate bit mask for the specified

flags parameter.

ret& = VBdaqAdcSetMux&(handle&,0, 7, DgainX1&, DafAnalog&+DafUnipolar&)

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