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Precise timings

vvvv beta general
#1

Hi all,

i’m trying to control a sensor that need very precise timings.

I need to read an analog output from arduino at 30 ms after the start of an LFO of 100ms as Period.

But the = node often don’t put out any values and so i don’t have a trigger for reading Arduino.

precise timing.v4p (4.9 kB)

#2

I’m trying with different nodes, but they all give me the same result with the same epsilon: they are loosing cycles not detecting the value range the main lfo cycle.

I’m trying also with mainloop and try to set it on very fast FPS (250fsb without render window here on my machine) but this doesn’t help because vvvv still can’t detect every values.

Please have a look, if there is something wrong in my approch or if it’s a vvvv limit.

Peace
Giorgio

precise timing2.v4p (20.3 kB)

#3

Hi E1n

I think it is the use of the delay that causes your problem. try using monoflop instead.

I have attached an example.

/sunep

timing.v4p (9.5 kB)

#4

hello e1n,

vvvv only updates the nodes when a frame is rendered. with 200fps this is approx. every 5ms. means a lfo with 0.1 sec has only 20 steps. if you want to be sure that you get a trigger in every cycle you should use a > to check if the lfo is over 0.3 and then make a bang with TogEdge.

precise timing3.v4p (19.2 kB)

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