Key Topics : Arduino Hardware Components, Arduino I/Os and other connections
Let's identify the main hardware components of an Arduino Uno Board
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| Arduino uno board hardware components (Photo credit : arduino.cc) |
A : USB Type - B Connector (to talk with computer)
B : 2.1 mm DC Barrel Jack
C : Voltage Regulator (6V-20V Limit)/(7V-12V Recomended)
D : Over Current Protection
E : 16MHz Regulator
F : ATmega16U2 (Programmed as a USB to TTL-Serial Converter, Note : Some boards had options like CH340 IC and FTDI Converter)
G : Reset Switch
H : RX (Receive) and TX(Transmit) indicators for Serial Communication
I : ICSP -In Circuit Serial Programming (USB Interface)
J : LED connected to pin 13
K : ATmega328 microcontroller
L : ICSP (for ATmega328P)
M : Power On LED
Arduino I/Os and other connections
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| I/O and other connections |
2 : SDA - Serial Data (I2C Communication, Wire Communication in Atmel devices)
3 : AREF - Analog Reference (Can be used to set the upper limit of Analog Inputs)
4 : GND
5 : General Inputs/Outputs ,Pins with ~ symbol supports PWM(Pulse Width Modulation Outputs
6 : TX : Transmit (Serial Communication)
7 : RX : Receive (Serial Communication
8 : Pins with ADC converters (Analog Inputs)
9 : Vin (Input power before regulator, Recommended Voltage is 7V-12V)
10 : 5V (5V bus of Arduino, Can be used to power up sensors, shields etc
11 : 3.3V (can be used to power 3.3V operated devices, sensors, modules etc)
12 : RESET : Reset Pin is useful in occasions where we use it as a programmer etc
13 : IOREF : Indicates the corresponding I/O voltage of the respective board ,(ex:Uno-5V, Due-3.3V)
