Example code to control an LED connected to an imp. It makes use of the imp’s PWM_OUT GPIO pin setting.

pwmLed.device.nut

// Assign a global variable, led, to the imp001 pin to which the LED is connected
led <- hardware.pin9;

// Configure it for PWM output
led.configure(PWM_OUT, 1.0 / 400.0, 0.0);

// Record the state and delta of the LED's cycle
ledState <- 0.0;
ledChange <- 0.05;
 
// Define a function to pulse the LED
function pulse() {
    // Write the state value to the pin
    led.write(ledState);
	
    // Change the state value
    ledState = ledState + ledChange;
	
    // Check if we're out of bounds and flip 'ledChange' if we are
    if (ledState >= 1.0 || ledState <= 0.0) ledChange = ledChange * -1.0;
	
     // Schedule the loop to run again in 0.05 seconds
     imp.wakeup(0.05, pulse);
}

// Start the loop by calling pulse()
pulse();