Go Down

Topic: A question about the internal resistors for pins 2 and 3 on Arduino UNO (Read 285 times) previous topic - next topic

Markussgr

When setting a pin's pinMode to INPUT_PULLUP it uses an internal 20-50kohm resistor. Source

On the Arduino UNO, when setting the pinMode for pins 2 or 3 to INPUT_PULLUP, do both pins' internal resistors go to the same ground or does each internal resistor have it's own ground?

I intend to use both interrupt pins to do different functions, one function for when the pin reads from HIGH to LOW (FALLING) and a continuous action for when the pin reads LOW.

That is all, sincrely
Markuss

TheMemberFormerlyKnownAsAWOL

The resistors go to Vcc, not ground.
They are individual resistors, one per pin.

wolframore

perhaps this will make it easier to understand:

a pull up "pulls up" the voltage when there is no connection to ground. So the input senses 5V until a switch is activated which causes it to go LOW.

Bad Boys Rate Our Young Girls But Violet Goes willingly - Get Some Now :) - ELI the ICE man

PerryBebbington


Quote
Do both pins' internal resistors go to the same ground or does each internal resistor have it's own ground?
There is only one ground. More to the point, there is only one 0V, which is often treated as being the same thing as ground, as the two are often connected together.

If you are not sure how many grounds there are, go outside and have a look round, how many grounds do you see?


Go Up