mirror of
https://github.com/tinygo-org/tinygo.git
synced 2026-08-10 05:53:39 +00:00
Ayke van Laethem
72acda22b0
This commit refactors PWM support in the machine package to be more flexible. The new API can be used to produce tones at a specific frequency and control servos in a portable way, by abstracting over counter widths and prescalers.
75 lines
1.6 KiB
Go
75 lines
1.6 KiB
Go
package main
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// This example demonstrates some features of the PWM support.
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import (
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"machine"
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"time"
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)
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const delayBetweenPeriods = time.Second * 5
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func main() {
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// Delay a bit on startup to easily catch the first messages.
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time.Sleep(time.Second * 2)
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// Configure the PWM with the given period.
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err := pwm.Configure(machine.PWMConfig{
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Period: 16384e3, // 16.384ms
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})
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if err != nil {
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println("failed to configure PWM")
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return
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}
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// The top value is the highest value that can be passed to PWMChannel.Set.
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// It is usually an even number.
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println("top:", pwm.Top())
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// Configure the two channels we'll use as outputs.
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channelA, err := pwm.Channel(pinA)
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if err != nil {
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println("failed to configure channel A")
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return
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}
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channelB, err := pwm.Channel(pinB)
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if err != nil {
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println("failed to configure channel B")
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return
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}
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// Invert one of the channels to demonstrate output polarity.
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pwm.SetInverting(channelB, true)
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// Test out various frequencies below, including some edge cases.
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println("running at 0% duty cycle")
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pwm.Set(channelA, 0)
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pwm.Set(channelB, 0)
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time.Sleep(delayBetweenPeriods)
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println("running at 1")
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pwm.Set(channelA, 1)
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pwm.Set(channelB, 1)
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time.Sleep(delayBetweenPeriods)
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println("running at 25% duty cycle")
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pwm.Set(channelA, pwm.Top()/4)
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pwm.Set(channelB, pwm.Top()/4)
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time.Sleep(delayBetweenPeriods)
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println("running at top-1")
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pwm.Set(channelA, pwm.Top()-1)
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pwm.Set(channelB, pwm.Top()-1)
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time.Sleep(delayBetweenPeriods)
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println("running at 100% duty cycle")
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pwm.Set(channelA, pwm.Top())
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pwm.Set(channelB, pwm.Top())
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time.Sleep(delayBetweenPeriods)
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for {
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time.Sleep(time.Second)
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}
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}
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