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Topic: Arduino breadboard 5V pin? (Read 642 times) previous topic - next topic


Hi group,

This is my first post on this forum. Yesterday I received my Arduino Inventors Kit and I love it! This is my first experience with microcontrollers and electronics and I just wire everything up like it's described in the guide. I started with the first example in the guide (blinking LED). The guide tells me to place a wire between the breadboard and the following pins on the microcontroller: 5V, GND and 13  pins 5V, GND. Also a resistor is placed to connect the LED with the GND on the breadboard. What is the resistor for and why is it on the GND of the LED and not between, like a bridge, the pin 13 of the microcontroller and the LED. I also noticed that when I remove the wire between the 5V and the breadboard everything is still working? How is this possible, I thought it was there for the current to flow from the microcontroller to the breadboard?!

Hope anyone could help me with this as I really want to learn more of it  :)



The resistor should from 13 to anode of LED, cathode to ground, this limits the current flow from the arduino pin to avoid damaging the pin. Writing High to 13 will turn the LED on.
I believe other examples will use 5V and gnd on the breadboard.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.


The resistor can be in any part of the LED circuit to limit its current - when components are 'in series' like this they must carry the same current no matter what order they are in the series.
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]


Thanks, your replies were very helpful!

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