PWM

The pwm module supports PWM(Pulse Width Modulation). Use require('pwm') to access this module.
Class: PWM
An instances of PWM represents a PWM object.
new PWM(pin[, frequency[, duty]])
pin <number> The pin number which can support PWM function.
frequency <number> The PWM frequency in Hz. Default: 490Hz
duty <number> The PWM duty cycle between 0.0 and 1.0. Default: 1.0
// Generate 1000 Hz 50% duth PWM signal on the pin 1.
var PWM = require('pwm').PWM; 
var pwm = new PWM(1, 1000, 0.5); // Create the PWM instance with pin 1
pwm.start(); // Generate PWM signal
// ...
pwm.stop(); // Stop PWM signal
pwm.close(); // Close PWM port.
pwm.start()
Start to generate PWM signal.
// Generate 1000 Hz 30% duth PWM signal on the pin 1.
var PWM = require('pwm').PWM; 
var pwm = new PWM(1, 1000, 0.3); // Create the PWM instance with pin 1
pwm.start(); // Generate PWM signal
pwm.stop()
Stop to generate PWM signal.
// Generate 1000 Hz 50% duth PWM signal on the pin 1.
var PWM = require('pwm').PWM; 
var pwm = new PWM(1, 1000, 0.5); // Create the PWM instance with pin 1
pwm.start(); // Generate PWM signal
delay(100); // Wait 100ms.
pwm.stop(); // Stop PWM signal
pwm.getFrequency()
Returns: <number> PWM frequency of the PWM instance.
Get the PWM frequency.
// Generate 1000 Hz 50% duth PWM signal on the pin 1 and print the frequency
var PWM = require('pwm').PWM; 
var pwm = new PWM(1, 1000, 0.5); // Create the PWM instance with pin 1
console.log(pwm.getFrequency());  // Print current PWM frequency.
pwm.setFrequency(frequency)
frequency <number> PWM frequency of the PWM instance.
Set the new PWM frequency.
// Generate 1000 Hz 50% duth PWM signal on the pin 1 and print the frequency
var PWM = require('pwm').PWM; 
var pwm = new PWM(1, 1000, 0.5); // Create the 1000 Hz PWM instance with pin 1
pwm.setFrequency(500); // Change the PWM frequency to 500 Hz.
pwm.getDuty()
Returns: <number> PWM duty of the PWM instance.
Get the PWM duty.
// Generate 1000 Hz 50% duth PWM signal on the pin 1 and print the duty
var PWM = require('pwm').PWM; 
var pwm = new PWM(1, 1000, 0.5); // Create the PWM instance with pin 1
console.log(pwm.getDuty()); // Print current PWM duty.
pwm.setDuty(duty)
duty <number> PWM duty of the PWM instance.
Set the new PWM duty.
// Generate 1000 Hz 50% duth PWM signal on the pin 1 and print the duty
var PWM = require('pwm').PWM; 
var pwm = new PWM(1, 1000, 0.5); // Create the PWM instance with pin 1
pwm.setDuty(0.7); // Change the PWM duty to 70%.
pwm.close()
Close the PWM port.
// Generate 1000 Hz 50% duth PWM signal on the pin 1.
var PWM = require('pwm').PWM; 
var pwm = new PWM(1, 1000, 0.5); // Create the PWM instance with pin 3
pwm.start(); // Generate PWM signal
// ...
pwm.stop(); // Stop PWM signal
pwm.close(); // Close PWM port.
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