As shown in figure above arduino UNO Uno is a microcontroller board based on the ATmega328P (datasheet). It has 14 digital input/output pins of which 6 can be used as PWM outputs analog or PWM output means you can generate any value between 0 to 5 volt from these six pins , and 6 analog inputs, These pins are use to generate or receive voltage from the outer world . The ATmega328 on the Arduino Uno comes preprogrammed with a bootloader that allows you to upload new code to it without the use of an external hardware programmer. It communicates using the original STK500 protocol .
Since arduino uses Atmega328 microcontroller which is AVR family , so i always recommend and suggest to learn AVR family and do some research on AVR before starting to arduino .
arduino pin description
- Vin. The input voltage to the Arduino board when it's using an external power source (as opposed to 5 volts from the USB connection or other regulated power source). You can supply voltage through this pin, or, if supplying voltage via the power jack, access it through this pin.
- 5V.This pin outputs a regulated 5V from the regulator on the board. The board can be supplied with power either from the DC power jack (7 - 12V), the USB connector (5V), or the VIN pin of the board (7-12V). Supplying voltage via the 5V or 3.3V pins bypasses the regulator, and can damage your board. We don't advise it.
- 3V3. A 3.3 volt supply generated by the on-board regulator. Maximum current draw is 50 mA.
- GND. Ground pins.
- IOREF. This pin on the Arduino board provides the voltage reference with which the microcontroller operates. A properly configured shield can read the IOREF pin voltage and select the appropriate power source or enable voltage translators on the outputs to work with the 5V or 3.3V.
- TX / RX ; Tx pin is used to transmit data through serial port and RX pin is used to receive data through serial port
- RESET : reset button is pressed when you need to reset the whole execution of the program , program start run from the beginning if you pressed this pin .
- AREF:This is reference pin or ground pin for analog input and output
- getting started with blinky
- different methods of programming
- LED array (display eight LEDs serially)
- Display message on liquid crystal display(LCD)
section-4. introduction to functions and library
section-5. input and output
section-6. sensors and transducers
section-7. motors and relay interfacing
section-8. Liquid crystal display(LCD) interfacing
section-9.seven segments interfacing
section-10.timer and counters
section-12.pulse width modulations (PWM)
section-14.using ethernet shield