I am generating a DC signal in LabVIEW and inputting it into an analog input pin on my Arduino. I am using AnalogRead, reading 1 value every 100 ms. The values that Arduino is receiving (when converted back to volts) are not consistent with the signal that I am outputting from LabVIEW. Thus far, it is difficult to tell where the problem is (Arduino or LabVIEW). Is there something obvious I am missing? Has anyone tried this type of setup before?
Electrical noise would be a classic cause of problems like this but as others said more information is required to solve the problem. Are you running the wires a long distance? Are the wires twisted pair? Shielded? etc..