servo-balayage.ino
The Servo library generates the control pulse (1-2 ms) and sweeps the angle end to end. Feeding a mid-size servo from a dedicated 5 V rail avoids brown-out resets from current spikes.
Hardware required
An Arduino Duemilanove (ATmega168 or 328P, 16 MHz, 5 V) with its mini-USB-B cable; the serial port appears once the FTDI driver is installed. 1 standard servo (SG90/MG90S) + recommended external 5 V supply.
Wiring
Orange (signal) to pin 3, red to +5 V, brown to GND (common ground with the board).
How it works
myservo.write(angle) sends a pulse whose width maps the angle; 5° steps every 50 ms give smooth motion. In the Arduino IDE, select « Arduino Duemilanove » (or « Diecimila » for very old boards) and the FTDI port, then Upload. The ATmega168 leaves only 14 KB for the sketch.
Going further
Add a potentiometer on A0 for a position → servo feedback loop (robot radar).
servo-balayage.ino
// Balayage servo 0..180 degres avec la bibliotheque Servo.
#include <Servo.h>
Servo myservo;
int angle = 0;
int sens = 1;
void setup() {
myservo.attach(3); // broche avec pin signal du servo
Serial.begin(9600);
}
void loop() {
myservo.write(angle);
angle += sens * 5;
if (angle >= 180 || angle <= 0) sens = -sens;
delay(50);
}