Tutorial 02 for Arduino: Buttons, PWM, and Functions

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You can download the parts list and the code from this episode on my website:
http://jeremyblum.com/2011/01/10/ardu...

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• Category

  Science & Technology

[André Marín García]

The only thing i don't understand is the use for the first resistor, the one u use on minute 4:15 :(

can someone explain it again?

[Cameron Belt]

You want the signal from the button to be low when it is not pushed but you also want to create a high signal that goes from the power into the arduino input pin to do this you connect a resistor of large resistance. it "drains" any voltage to ground keeping it low when the button is inactive and when it is pushed most of the current(thats why a large one is needed) flows into the input pin and not back into ground that the resistor is connected to. hopefully that makes some sense

[jaredanwyl]

Figured it out.

[jaredanwyl]

I'm having a weird issue. My switches (in all examples) seem to be always on. I can use a wire and inserting it acting like a switch works correctly. When i use a switch pressing the button does nothing. (basically current is already flowing) Therefore its acting like a wire and not allowing me to use it like a switch, any ideas?

[RebalanceGaming]

You don't "really" need it. But basically it makes sure that there is NO current flowing through the button until it is pressed. i'm not too sure why it is there either, because there shouldn't be any "leakage" of power through the switch....

[Wade Hawkins]

I'm really confused by how the ledOn variable was set with a default value of "false" instead of "low"? Can we use the terms "false" and "low" interchangeably? That wasn't stated in the tutorial.

[Leinad581]

i was so confused as the led was already turned on, and when i pressed the switch the led turned off, i went onto the arduino.cc website and i got the code and the code from there worked perfectly, i found out that it didnt work at first is because ive got the unr r3 the newest version and you have got the uno r2 at least thats what i think happened)

[sebomstian]

He explains that very nicely in the next part of this series.

[Chris Schmitz]

Every class, like setup and loop are in this case, has to specify whether it is void, or whether it returns a variable, like, say, an int- classes can be called upon/run by other classes, and the return type of the class that's called upon has to match the context in which it is called. Hope that makes sense.

[rdang16]

dude. you are awesome. thanks for the vids

[dsrjth]

is it possible to use this code for multiple buttons? if yes how?