C# https://dotnetfiddle.net/afyTvh https://dotnetfiddle.net/afyTvh using System; using System.IO; using System.Threading; public class B

C# https://dotnetfiddle.net/afyTvh https://dotnetfiddle.net/afyTvh using System; using System.IO; using System.Threading; public class Blink { const string FilePath = @"/sys/class/leds/beaglebone\:green\:usr0/brightness"; const int BlinkDelay = 2000; public static void Main() { using (var writer = new StreamWriter(FilePath)) { for (var state = true; true; state = !state) { writer.Write((state ? 1 : 0).ToString("00")); Thread.Sleep(2000); } } } } Reactive Extensions (C#) https://dotnetfiddle.net/bpOF5e https://dotnetfiddle.net/bpOF5e Observable .Repeat(Observable.Unit) .Select((index, _) => index % 2) .Select(string.Format({0:00}) .Delay(TimeSpan.FromSeconds(2)) .Aggregate( new StreamWriter(@"/sys/class/leds/beaglebone\:green\:usr0/brightness"), writer => (writer, state) => writer.Write(state) ) .Subscribe(writer => writer.Close());