Compter des impulsions à fréquence variable

[evuoj]

Bonjour,

Je récupère deux signaux carrés déphasés de 90° qui ont la même fréquence mais variable, je n'arrive pas à compter les impulsions pour certaines fréquences qui semblent être toujours les mêmes. Je tiens également compte du signe de déphasé qui me permet d'additionner ou de retrancher les impulsions. Ma fréquence varie entre 1hz et 50hz.

Pouvez-vous me donner quelques indices ?

[evuoj]

Hello,

I get back two out of step square signals of 90 ° which have the same frequency but the variable, I do not manage to count the impulses for certain frequencies which seem to be always the same. I also take into account the sign of disorientated which allows me to add or to deduct the impulses. My frequency varies between 1hz and 50hz.

[Guillaume_H]

Hi,

Thank you for posting your question on National Instruments' forums.

I guess you are French, but in order to let the other users of this forum understand our discussion I will answer in English.

If you want to ask your question in French, you could use the dedicated part of this discussion forum.

As for your question, I will need some more details in order to help you efficiently.

What device are you using to acquire the square signals? Are you trying to use a specialized DAQ counter board?

What are the frequencies that don't seem to be acquired correctly?

Are you using TTL signals?

Are you programming with DAQmx, under which operating system and LabVIEW version?

If you are a little more specific about the measurement system you are using, it will be easier for me to help.

I thank you in anticipation for your answer.

Best regards,