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Settling time for DAQ

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What is the best way to increase settling time on Visual C++ measurements of the PXI-6255 A to D? We needed to make some hardware changes that resulted in a measurement via a high-resistance voltage divider (24.7k and 100k) with secondary measurements on a near-ground voltage. The switching between the two sources leads to ghosting/crosstalk effects. We do not have a way to make hardware changes at the moment. Decreasing sampling frequency only helps to a certain point, after which the voltage reading is still low.

 

 

I attempted to use the function daqmxsetswitchdevsettlingtime but have been unable to find documentation regarding the first parameter, char deviceName[]. What is the Device Name?

 

If this function is depreciated, is there a replacement function?

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Hey GoodSirEric,

 

Are you using an NI switch? 

 

http://zone.ni.com/reference/en-XX/help/375472G-01/switch/extra_settling_time/

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Hello TwinTwo!

 

No, I am using an Analog to Digital card (PXI-6255) and creating a session with DAQmxCreateTask("",&taskHandleAtoD);

 

niSwitch_SetAttributeViReal64() is not recognized as a valid function because I have not included the necessary switch header files. Do the switch functions accept a task handle created with DAQmxCreateTask(), and can they apply settings to Analog to Digital cards?

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Solution
Accepted by GoodSirEric
NI Switch functions only apply for NI Switch hardware. What you want is to change the convert clock to alter the inter-channel delay.

http://digital.ni.com/public.nsf/websearch/65E7445DB1AA5DC586256A410058697B?OpenDocument
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Solution
Accepted by GoodSirEric

Dennis is right! In that link you can find how to allow additional settling time, this other links might be helpful for you to understand a little more:

 

http://digital.ni.com/public.nsf/allkb/42484E84DA98053686256D32006E0494

 

http://zone.ni.com/reference/en-XX/help/370471W-01/mxcprop/func1848/

 

http://zone.ni.com/reference/en-XX/help/370471W-01/mxcprop/attr1848/

 

https://decibel.ni.com/content/docs/DOC-14548

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Thanks! Those resources were extremely helpful!

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