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Author Topic: Problems with analogRead  (Read 471 times)
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i'm noob with analogic electronics....
 
can anyone answer those questions?
 
why do i get large oscillation values from any analog port even though it isn't linked to any circuit'???
 
are there any diference between the analogRead and the voltimeter values????
 
thanks
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If the analog in pin is not linked to any circuit, it is floating, which means it can read any value.  What is the purpose of reading the value from a pin that is connected to nothing?
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oh it was just a test i made to see what value i got... and when a i saw that oscillation i was worried thinking my arduino is crashed or something like that

thanks for the explanation
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If the analog in pin is not linked to any circuit, it is floating, which means it can read any value.  What is the purpose of reading the value from a pin that is connected to nothing?

Isn't that an okay way to seed your random number generator? smiley
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There are certainly entropy generators which use background noise as an entropy source (sadly the only one I can think of off the top of my head comes from sparkfun].

Many use only a few bits from the acquired signal though; IIRC this has something to do with Johnson noise being Gaussian.
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iDuino - MaxSerial - [url=http://spi

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