Synchronize Correlated Digital Output with Analog Input Using NI-DAQmx

[John_P1]

Overview:
This example uses DAQmx to synchronize finite generation and acquisition of Correlated Digital Output with an Analog Input Task respectively.

Descriptions:
Correlated I/O enables synchronization of on board digital I/O lines to a clock reference. Digital and Analog samples can be synchronized in time by sharing the AI clock as the source of your digital I/O clock. You may also use the Counter Output pulse as the Source of Digital Timing. Hence, set the Source for Digital Timing as ai/SampleClock.This  example will work on any device that uses DAQmx and supports Correlated  Digital I/O. To perform Correlated Digital I/O on 9172 Chassis,  you need a Correlated Module in slot 1-4 of the chassis.

Requirements:

1. LabVIEW 2012 or compatible.
2. NI-DAQmx 15.5.1 or compatible.

Steps to Implement or Execute Code:

1. Set all the control values on the front panel corresponding to the physical channel to be used on the DAQ device.
2. Run this VI.
3. Monitor the analog input voltage measured and ramp signal generated from specified channels.

Block Diagram Steps:

1. Creates channels to measure voltage and to generate digital signals  
2. Sets the source of the Sample Clock, the rate of the Sample Clock, and the number of samples to acquire or generate.
3. Generates an array containing a ramp pattern and write to digital output lines.
4. Transitions the tasks to running state to begin measuring and generating data.
5. Reads the waveform from the analog input channel and waits for the digital output generation to complete.
6. Clears the tasks.
7. Displays any error occurs.

**This document has been updated to meet the current required format for the NI Code Exchange.**

[by_182]

This file why it can not be used on hardware usb-6009?

[by_182]

This file why it can not be used on hardware usb-6009?

Error -200077 occurred at Property Node DAQmx Timing (arg 1) in DAQmx Timing (Sample Clock).vi:4730001->Correlated Finite DO with AI.vi

Possible reason(s):

Requested value is not a supported value for this property. The property value may be invalid because it conflicts with another property.

Property: SampTimingType

Requested Value: Sample Clock

Possible Values: On Demand

Task Name: _unnamedTask<0>

[crossrulz]

Because the USB-6009 does not have hardware timed DIO, only software timed DIO.  Meaning it cannot output digital waveforms as this example is doing.

[by_182]

(Bahasa)

Terimakasih atas jawabnya.

selanjutnya, apa yang harus dilakukan agar program tersebut dapat berjalan

pada USB-6009? apakah tidak bisa?

(English)

Thank you for your answer

*Furthermore, what should be done so that the program can run on USB-6009?

would it not be?*

2016-06-01 23:09 GMT+07:00 crossrulz <web.community@ni.com>:

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[crossrulz]

by_182 wrote:

*Furthermore, what should be done so that the program can run on USB-6009?

would it not be?*

                   

The USB-6009 simply does not have the capability to run this code.

[by_182]

what can I obtain a compatible file for usb-6009? please help me

I will use an analog as an input and digital as ouput.

2016-06-02 17:06 GMT+07:00 crossrulz <web.community@ni.com>:

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[TaoCui]

I have a question regarding this example.

I have a slower digital module, for example NI9422 250us response time. I have a faster analog module, for example NI9220 10us sample interval. If I correlate NI9422 to NI9220, I can run the sampling program at the highest 10us interval. Then, what does this mean for digital module? Does its result get interpolated?