Add tour to explain PWM #454
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I forgot this, this should not have been committed.
This update includes a few new features: * Better error reporting for type errors (they now include a range). * PWM support. * LED blink/fade support when connected to a PWM. * New part: a servo motor (using PWM)
This tour includes blinking LEDs, fading LEDs, and controlling servos.
deadprogram
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May 2, 2025
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| We get a channel number back. One PWM peripheral typically has 2-4 channels, which can be connected to certain pins. Which pins can be used depends a lot on the hardware, which we'll [get to later](../multiple/#finding-the-correct-pwm-peripheral-and-pins). For now, all you need to know is that the PWM channel is now connected to a single GPIO pin. | ||
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| To actually make the LED blink, we will set the duty cycle to half the "top" value of the LED: |
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Perhaps define "duty cycle" here.
deadprogram
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May 2, 2025
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| Servos are controlled using a form of pulse-width modification (PWM) to control their position. Every 20ms or so (the precise interval doesn't matter too much) a pulse of 1ms to 2ms is sent that indicates the target position for the motor. The pulse width is what matters here: 1.5ms indicates the center position, 1ms all the way to the right, and 2ms all the way to the left. |
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Tell us what a servo is, please.
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This tour explains how to do the following: