pwm

import {Pwm} from 'mikro/pwm'

Control PWMPulse-Width Modulation output for LEDLight-Emitting Diode dimming, motor speed control, servo positioning, and other analog-like outputs.

Usage

import {Pwm} from 'mikro/pwm'

const led = Pwm(20, {freq: 5000, duty: 0.5}).orPanic('Failed to set up the LED')

// Fade from current duty to 100% over 2 seconds
await led.fade(1.0, 2000)

led.end()

Functions

Pwm(gpio, options)

function Pwm(gpio: number, options: PwmOptions): Result<Pwm, PwmError>

Claims the GPIOGeneral-Purpose Input/Output pin, creates a PWMPulse-Width Modulation output on it and returns a Result with the handle. The pin must be able to drive a signal, or you get InvalidGpio. If another handle, a peripheral or the console holds it, you get GpioInUse.

Parameters:

• gpio: GPIOGeneral-Purpose Input/Output number
• options: see PwmOptions

Methods

pwm.duty(value?)

duty(): Result<number, PwmError>
duty(value: number): Result<void, PwmError>

Get or set the duty cycle (0.0–1.0). Called without arguments, returns the current duty. Called with a value, sets it. A value outside 0 to 1 returns InvalidParam.

led.duty(0.75).orPanic('Failed to set duty') // set to 75%
const current = led.duty().orPanic('Failed to read duty')

pwm.freq(value?)

freq(): Result<number, PwmError>
freq(value: number): Result<void, PwmError>

Get or set the frequency in Hz. Same get/set pattern as duty().

pwm.fade(targetDuty, durationMs)

fade(targetDuty: number, durationMs: number): Promise<Result<void, PwmError>>

Hardware-accelerated fade to the target duty cycle over the given duration. This uses the ESP32's LEDCLED Controller (ESP peripheral) hardware fading, so the fade runs without CPUCentral Processing Unit involvement. The promise resolves when the fade completes. If a fade is already running on the same output, fade() waits for it to finish before starting, and the event loop is blocked while it waits. Errors found before the fade starts, such as a target outside 0 to 1, come back in the resolved Result.

await led.fade(0, 1000) // fade to off over 1 second

pwm.end()

end(): void

Stops the PWMPulse-Width Modulation output and releases the hardware channel and the GPIOGeneral-Purpose Input/Output pin. Calling it again does nothing. A fade in progress resolves with ok(). After end(), setters and fade() do nothing, getters return the last value, and the first such call prints a warning. The handle keeps the hardware and its GPIOGeneral-Purpose Input/Output pin until you call end(), even when your code no longer refers to the handle.

Types

PwmOptions

interface PwmOptions {
  freq: number // frequency in Hz, 1 to 40000000
  duty?: number // initial duty cycle, 0.0–1.0 (default: 0)
}

Errors

PwmError

Variant	Fields	Description
GpioInUse	owner, message	Another handle, peripheral or the console holds the pin
InvalidGpio	message	The chip has no such GPIOGeneral-Purpose Input/Output, or the GPIOGeneral-Purpose Input/Output cannot drive a signal
InvalidParam	message	A frequency, duty cycle or fade duration is out of range
NoChannel	message	All LEDCLED Controller (ESP peripheral) channels are in use
NoTimer	message	All LEDCLED Controller (ESP peripheral) timers are in use by other frequencies
ConfigFailed	message	ESP-IDFEspressif IoT Development Framework rejected the LEDCLED Controller (ESP peripheral) configuration; message names the call and error
DutyFailed	message	Failed to set duty cycle
FreqFailed	message	Failed to set frequency
FadeFailed	message	Hardware fade failed