Arduino uno User Manual

Serial Communication Using Various Languages
When working with the Arduino, you often have to talk to it using a serial
port. In this section, you’ll learn how to do that in various programming lan-
guages. For demonstration purposes, we’ll use the same Arduino sketch for
all of them:
SerialProgramming/AnalogReader/AnalogReader.ino
const unsigned int BAUD_RATE = 9600;
const unsigned int NUM_PINS = 6;
String pin_name = "";
boolean input_available = false;
void setup() {
Serial.begin(BAUD_RATE);
}
void loop() {
if (input_available) {
if (pin_name.length() > 1 &&
(pin_name[0] == 'a' || pin_name[0] == 'A'))
{
const unsigned int pin = pin_name.substring(1).toInt();
if (pin < NUM_PINS) {
Serial.print(pin_name);
Serial.print(": ");
Serial.println(analogRead(pin));
} else {
Serial.print("Unknown pin: ");
Serial.println(pin);
}
} else {
Serial.print("Unknown pin name: ");
Serial.println(pin_name);
}
pin_name = "";
input_available = false;
}
}
void serialEvent() {
while (Serial.available()) {
const char c = Serial.read();
if (c == '\n')
input_available = true;
else
pin_name += c;
}
}
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Arduino uno Specifications

General

Form factor	Arduino
Certification	RoHS, FC, CE
Processor model	-
Processor frequency	- MHz
Microcontroller model	ATmega328
Microcontroller frequency	16 MHz
DC input voltage	7-12 V
Operating voltage	5 V
DC current per I/O pin	40 mA
Flash memory	0.032 MB
Maximum internal memory	- GB
SRAM (Static Random Access Memory)	2 KB
EEPROM (Electrically Erasable Programmable Read-Only Memory)	1 KB
Wi-Fi	No
Number of analog I/O pins	6
Number of digital I/O pins	14

Weight and Dimensions

Board dimensions	53.4 x 68.6 mm