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Topic: Potentiometer (Read 1 time) previous topic - next topic

000

Dec 23, 2008, 07:42 am Last Edit: Dec 23, 2008, 07:44 am by dev_000 Reason: 1
guys i am trying to take readings 4m a pot.. i am using the foll ckt...
http://www.mediafire.com/imageview.php?quickkey=ez5kmxdzyjn&thumb=5

intially wen i connected the ckt i got values ranging from 100 to 1024... now wen i am connecting the ckt (the same one) i am getting variations 4m 150 to 400 range... can anyone tell me y this happens???
here is the code i used...

int val;
void setup()
{
  Serial.begin(9600);
 
}
void loop()
{
     val=analogRead(2);
     Serial.println(val);
}

thanx in advance

Mike Mc

Maybe the pot is dirty or your Voltage source is not regulated and hence different each time you use it?

retrolefty

What is the value of your pot? If it is 4 meg-ohms ( I see 4m in your post) then that is much too high as the impedance of the input of the Arduino will act like a voltage divider thus lowering your readings. The link you attached shows using a 10k pot and that should work fine.

Lefty

000

#3
Dec 23, 2008, 11:46 am Last Edit: Dec 23, 2008, 12:47 pm by dev_000 Reason: 1
i am using a 10k pot... voltage source i am using is the one in the arduino... 5V port...
I would also like to know if something is faulty... voltage source isnt faulty chked it with a multimeter... any voltage i give should give a variation between 0- 1024 rite??

000

#4
Dec 23, 2008, 01:01 pm Last Edit: Dec 23, 2008, 01:01 pm by dev_000 Reason: 1
problem solved guys... it was a problem with the pot... changed it and it works gr8...  ;D

drone

#5
Dec 23, 2008, 07:48 pm Last Edit: Dec 23, 2008, 07:50 pm by drone Reason: 1
Quote

What is the value of your pot? If it is 4 meg-ohms ( I see 4m in your post)


I think he's trying to say "from" - it must be some new abbreviation - it's everywhere I'd expect "from" to be. =)

A note to the OP: be careful about abbreviating common words.  A lot of the abbreviations you might have a tendency to use when typing an SMS message, for example, will conflict with known abbreviations in the electronics world.

!c

Grumpy_Mike

Quote
A lot of the abbreviations you might have a tendency to use when typing an SMS message, for example, will conflict with known abbreviations in the electronics world.


Not to mention confuse old fuddy duddies like me.

If I said you were sick would that be good???
Apparently it depends on how old you are?  :-?

retrolefty

I'm too old to even know what SMS messaging means  ;)

Lefty

Mike Mc

I have to admit I hate abbreviations. people use them all the time in work and it drives me nuts.

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