Lesson 12 of 16

Sweep a servo

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#include <Servo.h> Servo arm; void setup() { arm.attach(9); // the servo's signal wire is on D9 } void loop() { for (int a = 0; a <= 180; a++) { arm.write(a); // turn to this angle, 0-180° delay(12); } for (int a = 180; a >= 0; a--) { arm.write(a); delay(12); } }

Stopped · Your code isn't running yet. Until you press Run, the board runs the program already on it.

Nothing printed yet. Press Run.

A servo turns to the angle you ask for and holds it. The Servo library sends a pulse every 20 ms: 1 ms wide for 0°, 2 ms for 180°.

Watch the arm sweep
What the pulse width means
Change the range and the speed

Pin	Connects to	What it does
`GND2`	The brown wire	Ground.
`5V`	The red wire	The motor's supply.
`D9`	The orange wire	The position pulse.

Wire it in

Sensors and actuators this board drives, with the real connections.

SG90 micro servoSupply 5 V
Brown to GND, red to 5V, orange to a pin (D9). Servo.attach(9) then write(0..180).
Part pin Board pin
GND GNDWire colour brown
VCC 5VWire colour red
SIG D9Wire colour orange
Careful
A moving servo can draw 250 mA and a stalled one 700 mA. More than one servo needs its own 5 V supply, with the grounds joined.

Part pin	Board pin
GND	GNDWire colour brown
VCC	5VWire colour red
SIG	D9Wire colour orange

All 16 parts on the Arduino Uno R3 page

Sweep a servo

Try it yourself

Serial monitor

Checks

Break it

Parameters

Wire it in

Sweep a servo

Try it yourself

Serial monitor

Checks

Break it

Parameters

Wire it in