Before start working with arduino, first we have to know what is arduino uno ? Arduino is a microcontroller platform by using that we can captured the imagination of electronics enthusiasts. It is very easy to use and because it is open source nature make it a great choice for anyone wanting to build electronic projects.
Now Arduino boards has a low-cost and very easy to use technology to create microcontroller based projects. With a little electronics, you can make your Arduino do all sorts of things, from controlling lights in an art installation to managing the power on a solar energy system.
So finding the answer of what is arduino uno ? we should know that Arduino is a small microcontroller board and it come with a universal serial bus (USB) plug to connect to your computer and a number of input and output ports that can be wired to external electronics such as motors, relays, light sensors, laser diodes, loudspeakers, microphones, and more. They can either be powered through the USB connection from the computer, from a 9V battery, or from a power supply. They can be controlled from the computer or programmed by the computer and then disconnected and allowed to work independently.
The heart of your Arduino is a microcontroller. A microcontroller really is a little computer on a chip. Inputs can read both digital and analog types. For that reason it opens up the opportunity of connecting many different types of sensor for light, temperature, sound, and more. Outputs can also be analog or digital. So, you can set a pin to be on or off (0 volts for off or 5volts for on) and this can LEDs on and off directly, or you can use the output to control higher power devices such as motors. They can also provide an analog output voltage. The microcontroller on an Arduino board is the 28-pin chip fitted into a socket at the center of the board. This single chip contains the memory processor and all the electronics for the input/output pins.
For Arduino UNO has six pins labeled as Analog In A0 to A5 can be used to measure the voltage connected to them so that the value can be used in a sketch. Note that they measure a voltage and not a current. Only a tiny current will ever flow into them and down to ground because they have a very large internal resistance. That is, the pin having a large internal resistance only allows a tiny current to flow into the pin.
For Arduino UNO has 13 pins for Digital connection and we can see it to the top connector and start on the right-hand side. Here we find pins labeled Digital 0 to 13. These can be used as either inputs or outputs.
So as we know microcontroller is a brain of Arduino, the microcontroller chip itself is the black rectangular device with 28 pins. The 28-pin microcontroller chip used on the Arduino Uno board is the ATmega328.