Pulse-width modulation (PWM)

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Section 3.8 Pulse-width modulation (PWM)

Subsection 3.8.1 Controlling brightness of an LED

# Drive an LED at various brightness levels using PWM

from machine import Pin, PWM

led = PWM(Pin(13))

led.freq(1000) # Hz, ranges from 1Hz to 40MHz
led.duty(512) # Fraction, ranges from 0-1024

Subsection 3.8.2 Controlling a servo motor

# Control the position of a servo using PWM
from machine import Pin, PWM

servo = PWM(Pin(23), freq=50)

# For my little SG90 micro-servos,
# 20 is full left, 130 is full right, 90 is about the middle
servo.duty(20)

Subsection 3.8.3 Square-wave sound with PWM

from machine import Pin, PWM

led = PWM(Pin(13))

led.freq(440) # 440Hz is A below middle C
led.duty(512) # Fraction, ranges from 0-1024