How can I get same volatage-frequency graph in output and input?

[Yun_Zhu]

I have two questions in this vi:

1.Why the xy graph show a point rather than a plot?How can I get a curve?

2.Why does not the detected frequency  follow the output frequency befor value 11?How can I get the same detected frequency with the output frequency?

3.How can I get the xy graph as the same as the xy graph 2? 

[Doug-B]

In order to get a continuous flow of data you need to use a chart rather than the graph that you are using.

Also, in order to get both sets of data to be graphed on the same chart you need to go to the chart on the front panel an expand the little dialog box where it says "plot 0" upwards and that will enable you to have "plot 0" and "plot 1" plot simultaneously on the same chart.

I am having a little trouble understanding what you are asking in your second question but hopefully these two tips will get you going in the right direction.

Good Luck,

Doug B

[Yun_Zhu]

Doug B,

I want the x-axes frequency and y-axes voltage.So,I didn't use a chart.

The second question is:

When I run the vi,the two frequency we get from input or output should be almost the same.But,they actually  are not before 11Hz.I want to know  why the detected frequency  did not follow the output frequency befor value 11Hz?How can I get the same detected frequency with the output frequency?

Yun

[Doug-B]

Yun,

There is a vi in LabVIEW called XY Chart Buffer.vi that allows the XY Graph to continually return the data that is fed to it which is what I believe you are attempting to do. See the exmple called XY Chart.vi in the Help>>Find Examples for a visual reference for how to make this work. 

As for the voltages being off, that sounds like a hardware issue. What devices are you using?

Doug B

[Yun_Zhu]

I search the "x-y chart"in help example.But,I couldn't open it because the toolkit.What should I do?

My DAQ card is 9201 and 9263

Thanks

[Kyle_K]

Hey Yun,

Try just using a search for "xy" and you should see it in the list. It is included with LabVIEW so you don't need any toolkits for it.

Kyle K.