Circuit: comes from root word circle, goes around and around, electricity flows like water. Requires the following 3 things: power (- & +), conductor, load.
Without a load, you've got a short circuit!
Your Arduino board:
There are several parts on the Arduino board, the most important parts that you will need to be familiar with right now are:
1. USB port: This is where you plug the usb cord in to connect the board to your computer, this is how you upload your code and it will also provide power to your board.
2. Barrel Jack: This is to provide power to your board from a wall wart (ac adapter) after you upload your code, you probably don't want it tethered to your computer anymore. You can use 5v, 9v, 12v to power your Arduino. An onboard voltage regulator will keep the board at 5v for you.
3. Reset button: This will start your code from the beginning, it does not delete or change your code. The only way to do that is to upload new code via USB.
4. LED indicators: One shows that the board is getting power, one shows when the board is receiving data (code is being uploaded), another shows when data is being transmitted (a program is running) and pin on is attached to pin 13 to test HELLO WORLD sketch (you can make it blink).
5. the pins: The little pin holes are where you can stick your jumper wires to create a circuit, different pins serve different purposes. Here are the basics:
a. 5v & 3v - these pins provide power out from the Arduino to your circuit, one
provides 3 volts and the other provides 5 volts. Think of this as the positive
power source for your circuit.
b. gnd pins - these are the ground pins. Everything that has power going into
it, needs a place for that power to return. That point of return is know as
ground, earth, or the negative that compliments the positive.
c. vin pin - power can go in here (5-12v) instead of the barrel jack or USB port
and power can also come out here (5v). It goes both ways! Useful to
permanently solder on a battery port or other power supply.
d. input/output pins: all of these pins can be used for input (information
coming in from sensors) or output (information going out to actuators).
there are 2 main types: analog and digital.
What's the difference between analog and digital on Arduino?
analog pins are labeled A0, A1, A2.... through A5
digital pins are simply labeled 1, 2, 3, 4, 5... through 13
But what's the difference?
Analog: Think of analog as a gray area, a spectrum of possibilities.
Very On, kinda on, sorta on, maybe on, a little on, mostly off, very off
Max, hi, med hi, med, med lo, lo, min, off
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc….