The Arduino Uno is a microcontroller board based on the ATmega328,Very popular on open source hardware and software.
- Operating Voltage-5V.
- Input Voltage (recommended)7-12V.
- Input Voltage (limits) 6-20V.
- DC Current per I/O Pin 40mA.
- DC Current for 3.3V Pin50 mA.
- Flash Memory32 KB.
- SRAM2 KB.
- EEPROM1 KB.
- Lock Speed 16 MHz.
- Most of these pins are used to connect to I/O devices.
- Arduino have 28 pins.
- It has 14 Digital I/O Pins (of which 6 provide PWM output).
- It has 6 Analog Input Pins.
Input / Output Pin
- Serial: 0 (RX) and 1 (TX).Used to receive (RX) and transmit (TX) TTL serial data.
- The External Interrupts 2 and 3 pin can be configured to trigger an interrupt on a low value, a rising or falling edge, or a change in value.
- The pins 3, 5, 6, 9, 10, and 11,Provide 8-bit PWM output.
- SPI: 10 (SS), 11 (MOSI), 12 (MISO), 13 (SCK) these pins support SPI communication.
- LED: 13.There is a built-in LED connected to digital pin 13.
- The Uno has 6 analog inputs, labeled A0 through A5, each of which provide 10 bits of resolution (i.e. 1024 different values).
- TWI: A4 or SDA pin and A5 or SCL pin, Support TWI communication.
- AREF.Reference voltage for the analog inputs.
- Reset.Bring this line LOW to reset the microcontroller.
- Typically used to add a reset button to shields which block the one on the board.