Raspberry Pi - PWM Output
In a PWM control script, the LED brightness does not change when adjusting the duty cycle variable. Which of these is the most likely cause?
In a PWM control script, the LED brightness does not change when adjusting the duty cycle variable. Which of these is the most likely cause?
medium📝 Debug Q7 of 15
Step-by-Step Solution
Solution:
Step 1: Check PWM initialization
If pwm.start() is not called, PWM signal does not begin, so duty cycle changes have no effect.Step 2: Evaluate other options
GPIO pins do support PWM via software; duty cycle above 100 is invalid but usually causes error; frequency 0 Hz is invalid but would cause error.Final Answer:
The PWM object was not started with pwm.start() -> Option AQuick Check:
pwm.start() needed to activate PWM [OK]
Quick Trick: Always call pwm.start() to begin PWM signal [OK]
Common Mistakes:
- Assuming hardware PWM is required
- Setting invalid duty cycle without error
- Ignoring pwm.start() call
Master "PWM Output" in Raspberry Pi
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