Signal Conditioning

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how can i measure frequency AND voltage AND temperature

currently, i made a temperature task and added my voltage channels to it with a "DAQmx Create Task.vi"

this all works fine and dandy. however, when i try to add a frequency input to another instance of "DAQmx Create Task.vi" or wire it instead of either voltage or temperature, i get an error:

Error -200559 occurred at DAQmx Create Task.vi
Possible reason(s):

Task cannot contain a channel with the specified channel type, because the task already contains channels with a different channel type.

Create one task for each channel type.

if i create a seperate task for my frequency reading, there is no way i can measure it along with my other readings... labview 6.1 never had this problem. unless im missi
ng something here, it seems like this is a step down from the previous version when labview didnt seem to care what kinds of signals you were measuring at the same time.
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Are you sure it's error 2000559? I am unable to find any documentation for that error in LabVIEW.

Regardless, it sounds like you could be going about creation of a DAQmx task incorrectly. It's true that with the DAQ Assistant you are not able to add more than a single type of measurement to the DAQmx task. The reason for this is because the DAQ Assistant is an Express VI which was created to aid in the creation of simplistic DAQ applications.

Measuring frequency is slightly different than most other types of measurements simply because not all National Instruments devices are capable of it. If you are trying to measure the frequency of an analog signal then you must be using either the SCXI-1126 or the SCC-FV01. Both of these devices are capable of converting
a frequency to an analog voltage, which would be required with the DAQmx Channel VI set to Analog Input > Frequency.

For an example on performing multiple types of measurements in a single DAQmx task check out knowledgebase entry 32JEOHW0 at http://digital.ni.com/public.nsf/websearch/89B7218072F1CAF686256DC500722B6E?OpenDocument. This knowledgebase explains a little bit about different types of measurements in the same task, as well as provides a link to an example program that accomplishes this task.
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yes im sure of the error number, i copied and pasted it directly from the error box. furthermore, the example program linked to that knowledgebase entry is the exact one that i based my code on that DOES NOT WORK FOR FREQENCY. my frequency signal is coming into a pci-mio-16e-4 card using 2 counters. i make a frequency global channel and wire it into my program to get that error. i've also tried making a task using the same input, and recieved the exact same error.
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any further suggestions?
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