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LM5 Reactor Lite - Sample Rate
#1
hi guys,

is it possbile to use the digitial input to count pulses? so i have a device which gives me a PWM signal with a changing frequency and i want to calculate the freuqency.
Is this possible with one of the digital inputs? how fast is the sample rate of the inputs?
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#2
Reactor lite does not support pulse meter. Pulse meter on other devices is not meant for high frequency measurement.

It is possible to convert PWM to more or less constant voltage with a simple RC (resistor + capacitor) low-pass filter, then measure it with analog input and convert back to frequency. It won't be very precise though.

Can you explain why do you need to measure this PWM signal and what is the frequency?
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#3
okay to make it easier i just have to count the pulses which occours. and then e.g. every 10 seconds i calcuate the diffrence the "measure" the frequency
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#4
Reactors with analog inputs can measure pulses that are not lower than 10ms. Frequency calculation from number of pulses per second is built in.

PWM measurement is a different story because for any value between 0% and 100% (not inclusive) the number of pulses per second is the same, only the pulse width is different.
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#5
okay lets break it down a little:
1) how i can archive the calcuation of the frequency?? i cant find any "function" to active this
2) the maximium amount of pulses per second should be around 12 times per second. i dont know the length of the pulses, i have to check this out first. Is it possible the count all these 12 pulses if they are longer then 10 ms each for example with an event script or is this to fast?
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#6
Hi
Did you look here?


Attached Files Image(s)
   
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#7
This is not supported on Reactor lite, only Reactor devices with analog inputs have pulse meter function.
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#8
(09.08.2018, 09:22)Daniel. Wrote: Hi
Did you look here?

oh okay thanks for that image. em with that image i realized...i got the wrong reactor Big Grin i only got digital inputs...sorry for the stupid question then, but thanks for your advice
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