Bill23
2008-03-06 00:10:07 UTC
Hi,
I'm new to LabView and am having trouble measuring the duty cycle of my signal, currently i'm using a cDAQ board with the NI 9205 analog input module to receieve the PWM signal. I've tried using the Pulse Measurement block from LabView 8.5 but it would appear that my period is too long so comes with the error "The waveform did not cross the mid reference level enough times to perform this measurement. Check the signal length, reference levels, and ref level units". Is there anyway around this or perhaps another way to calculate the duty cycle on a real time basis?
The frequency of my signal is around 0.8Hz so the period is ~1.25s. I'm just using DAQ assistant which outputs the data in dynamic data format (thick striped blue line) and plugging it into the pulse measurement block which appears to accept brown lines so there is a coersion dot in the way, would that affect anything? The indicators appear as arrays.
I have tried changing the continuous sampling rate to as low as 10Hz but still comes with an error and displays dubious values before it does. The signal ranges between 0-5V and is quite well defined.
I'm new to LabView and am having trouble measuring the duty cycle of my signal, currently i'm using a cDAQ board with the NI 9205 analog input module to receieve the PWM signal. I've tried using the Pulse Measurement block from LabView 8.5 but it would appear that my period is too long so comes with the error "The waveform did not cross the mid reference level enough times to perform this measurement. Check the signal length, reference levels, and ref level units". Is there anyway around this or perhaps another way to calculate the duty cycle on a real time basis?
The frequency of my signal is around 0.8Hz so the period is ~1.25s. I'm just using DAQ assistant which outputs the data in dynamic data format (thick striped blue line) and plugging it into the pulse measurement block which appears to accept brown lines so there is a coersion dot in the way, would that affect anything? The indicators appear as arrays.
I have tried changing the continuous sampling rate to as low as 10Hz but still comes with an error and displays dubious values before it does. The signal ranges between 0-5V and is quite well defined.
