Everything worked great on the first try, even the little example modifications. I just don’t understand WHY it worked.
I’m a programmer, so I can grasp what’s going on with the code, but I am pretty clueless with electronics.
I guess I’ll try to explain in my own words what’s happening…
The Uno I think is the only part I even partially understand. It runs the sketch. For this project, it’s sending (or NOT sending) a “voltage” (?) of electricity to a pin (#13). The Uno is also connected to the breadboard via the 5V and GND power. I don’t understand why 5V and GND is necessary if it’s already sending electricity to power the LED on pin 13?
The Breadboard: I have no idea what is going on with this There’s “Headers” which I’m guessing just hold the paper in place? There’s a 5V and GND wire coming for power. The LED lights up, controlled by the UNO through the wire on the same row. That’s where I really get confused though. The whole relation of the 5V/GND → Resistor+Pin13 → LED and why it’s set up that way on the breadboard I just don’t understand.
So I guess my question is, could someone explain to me like a 5 year old how each part is working electronically in relation to each other (and the breadboards role in it)?
Extra credit dumb question: Can I get electrocuted by touching the parts when it’s plugged in?
First, no you can’t get electrocuted. Worse case you are using a 9v power adapter plugged into the socket. That is 9VDC. The rest of the circtuit runs at 5VDC.
If you are simply turning on the LED already connected to Pin13 of the Arduino board, then the breadboard is doing absolutely nothing. This is the Surface Mounted LED that is right next to Pin13. In this case having any wires at all going to the breadboard are doing nothing for you.
If, as I suspect, you have placed a second LED on the breadboard, then here is the likely setup:
You would run a jumper directly from pin 13 (or whatever pin you chose) to the breadboard to the long leg of the LED (this will need to go through a resistor). This is, in fact sending the 5V board voltage to that pin when you tell the pin to go HIGH. The problem is you need a path to ground. So you have to carry the GND from the board over to the breadboard to complete the path. You can either send ground to the GND rail andf attach the short leg to the GND rail or you can actually just run another jumper straight to the GND pin of the Arduino thus completing the circuit.
In this configuration you don’t need 5V or GND running to the Breadboard.
If you are building a more complex circuit that includes more than one component, then it starts to make sense to put bring the 5V and GND to the breadboard. For a simple example, if you are simply using 3 differnt LED’s that you are turning on from 3 different pins. All three of these need a path to GND to complete the circuit. In order to do this, you will need to have the GND rail active since you don’t have enough GND pins on the Arduino. If you run the GND pin to the GND rail on the breadboard, these points are all electrically common. The same goes with the 5V rail.
Where you start needing the 5V rail is if you need to use a switch or another component that needs 5V like an RFID reader. For example, this weekend, I needed a button to supply 5V to the Arduino when I pressed it and I needed 5V to power an RFID reader. In order to do this I needed 5V on the breadboard so I could run it to multiple components.
glln:
The Uno I think is the only part I even partially understand. It runs the sketch. For this project, it’s sending (or NOT sending) a “voltage” (?) of electricity to a pin (#13). The Uno is also connected to the breadboard via the 5V and GND power. I don’t understand why 5V and GND is necessary if it’s already sending electricity to power the LED on pin 13?
Looking at the [[breadboard layout sheet](http://ardx.org/src/circ/CIRC01-sheet-OOML.pdf) you are correct, they really don't need to send the 5V to the breadboard. It's not being used for anything in this circuit. My guess is they have you do that just so you get used to always sending power and ground (so they don't get forgotten). The ground is needed though, as the resistor is connected to the ground (bus) which in turn is connected to the Arduino bround (needed to "complete" a circuit).
glln:
The Breadboard: I have no idea what is going on with this There’s “Headers” which I’m guessing just hold the paper in place? There’s a 5V and GND wire coming for power. The LED lights up, controlled by the UNO through the wire on the same row. That’s where I really get confused though. The whole relation of the 5V/GND → Resistor+Pin13 → LED and why it’s set up that way on the breadboard I just don’t understand.
Yes, the header pins are just there to holder the paper in place. I’m not sure what your question is re: the arrangement on the breadboard ? Are you unsure how the breadboard goes about making the electrical connections required or are you unsure about what electrical connections (between the components) are needed and why ? Are you looking for some basic explanation of circuit theory ? Maybe these tutorials will help …
There’s “Headers” which I’m guessing just hold the paper in place? There’s a 5V and GND wire coming for power. The LED lights up, controlled by the UNO through the wire on the same row. That’s where I really get confused though. The whole relation of the 5V/GND → Resistor+Pin13 → LED and why it’s set up that way on the breadboard I just don’t understand.