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Topic: Newbie question about Vcc (Read 1 time) previous topic - next topic

funkyguy4000

Oh, is this whole thing operating at 3.3V?  If you have enough power to send a HIGH signal to the microcontroller, then you can still use the button by feeding it 3.3V. 

What the button does is just make a circuit.  When its pressed, it completes the circuit.  Since the output is connected to the arduino, and if the whole thing is running at 3.3V and is using 3.3V logic, then getting a t 3.3V from the button will still send the HIGH signal. 

What voltage are you going to be using?  Is this a 3.3v pro mini or a 5v pro mini.
Accelerate to 88 miles per hour.

pgmartin

No need to use another pin to "feed signal".

You can activate the internal pull up, so you can forget about that extra resistor you are using.
You can achieve this by using:

Code: [Select]

pinMode(2, INPUT);
digitalWrite(2, HIGH);


More about it here: http://www.arduino.cc/en/Tutorial/DigitalPins

by using the internal pullup, you just use the switch to give a temporary connection to ground.

the-rebel-agent

#7
Aug 15, 2012, 07:56 pm Last Edit: Aug 15, 2012, 08:15 pm by the-rebel-agent Reason: 1
Wow! Thanks, good to know about that. Gracias Martin, yo tambien soy de Argentina.

PD: Encontre este ejemplo despues de investigar: http://www.arduino.cc/en/Tutorial/InputPullupSerial

Osgeld

arg! thats what I said, use the internal pullup

thats it, no candy for you!

(kidding, you can have some candy)

the-rebel-agent

Sorry I did not get it from the very fist time. Reading that tutorial found out about the INPUTPULLUP mode, that saves you 1 line of code BTW.

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