Keyestudio ARDUINO maker learning kit, Руководство пользователя

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The rotate angle of the servo motor is controlled by regulating the duty cycle of the
PWM(Pulse-Width Modulation) signal. The standard cycle of the PWM signal is 20ms
（ 50Hz ） .
Theoretically, the width is distributed between 1ms-2ms, but in fact, it's between 0.5ms-2.5ms.
The width corresponds the rotate angle from 0° to 180°. But note that for different brand motor,
the same signal may have different rotate angle.
After some basic knowledge, let's learn how to control a servomotor. For this experiment, you
only need a servomotor and several jumper wires.
Hardware required
9G servo motor*1
Breadboard jumper wire*several
Connection & sample program
There are two ways to control a servomotor with Arduino. One is to use a common digital sensor
port of Arduino to produce square wave with different duty cycle to simulate PWM signal and use
that signal to control the positioning of the motor. Another way is to directly use the Servo
function of the Arduino to control the motor. In this way, the program will be easier but it can only
control two-contact motor because for the servo function, only digital pin 9 ang 10 can be used.
The Arduino drive capacity is limited. So if you need to control more than one motor, you will
need external power.
Method 1