Instrument Control (GPIB, Serial, VISA, IVI)

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Demux of single channel ai

I have been all over the forums and documentataion for the last 10 days. Please help.

I have a 16 channel thermocouple switch that i have connected to a single analog input channel on my USB-6009 i am able to get very reliable measurements from it but so far i have had no luck in being able to graph the data acquired properly.

The issue is that all 16 channels wont seperater into seperate wave forms. it may have something to do with how i am acquiring but i should be able to demux the signals at the time of ascquistion. I just have not found a way to that is compatable with display.

From the looks of what i have found the device im using is a very basic set up the model is RTD-TS16 (Real Time Devices)I just wish that i could figure out how to display the data properly.

if any one out there knows how to demux a setup like this please help me out.
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I'm not familiar with this mux that you're using. Is it GPIB controlled or what? How are you controlling the mux? Is there a means to synchronize the start of the muxing and the start of your data acquisition? Without some sort of synchronization, you won't know which channel is which. When using NI components such as SCXI to mux multiple channels into a single DAQ, all of the syncronization is done for you in the NI-DAQ driver and you would automatically get a multi-channel reading.
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The method of Control is DIO so i only get the channel i want. The module has CJC compensation and amplification built in so no need to message any numbers other than a simple mulitplication.

I have atached a vi that works but is not elegant to say the least i was hoping to keep everything in arrays thru the length of the program. I will be reeding from the other 3 channels on the 6009 as well to get an additional 2 thermocouple measurments and a CJC reading.
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I think your example is pretty elegent as it is. The way you're doing things, you can wire a chart directly to the temp reading cluster. Multiple traces on a chart are done by creating a cluster of readings. Each time the VI is called, it will update the chart with the 16 channels. Charts are typically used to show data real time. In order to use a graph for multiple channels, you need a 2D array. Call this VI multiple times and create a 2D array from the temperature array output. You may have to transpose the 2D array to correctly display the different channels. this can be done with either the Transpose 2D Array function on the Array palette or right clicking on the graph and selecting it. I've attached a file that shows some of the different possibilites.
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Thank you for your exampls i will use them in the future. I really didnt want to resort to Cluster level individual values at acquire but now i see that it will work just fine especially due to the measurment frequency in the 1000 ms range. Thanks for you help.
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