예제 #1
0
        private static int Calibrate()
        {
            const int referenceCount = 1000;

            return(Enumerable.Range(0, referenceCount)
                   .Aggregate(
                       (long)0,
                       (a, i) =>
            {
                var t1 = new Interop.timespec();
                var t2 = new Interop.timespec();

                t1.tv_sec = (IntPtr)0;
                t1.tv_nsec = (IntPtr)1000000;

                var start = DateTime.UtcNow.Ticks;
                Interop.nanosleep(ref t1, ref t2);

                return a + ((DateTime.UtcNow.Ticks - start) * 100 - 1000000);
            },
                       a => (int)(a / referenceCount)));
        }
예제 #2
0
        /// <summary>
        /// Sleeps the specified delay.
        /// </summary>
        /// <param name="delay">The delay.</param>
        public static void Sleep(TimeSpan delay)
        {
            // Based on [BCM2835 C library](http://www.open.com.au/mikem/bcm2835/)

            // Calling nanosleep() takes at least 100-200 us, so use it for
            // long waits and use a busy wait on the hires timer for the rest.
            var start = DateTime.UtcNow.Ticks;

            var millisecondDelay = (decimal)delay.TotalMilliseconds;

            if (millisecondDelay >= 100)
            {
                // Do not use high resolution timer for long interval (>= 100ms)
                Thread.Sleep(delay);
            }
            else if (millisecondDelay > 0.450m)
            {
                var t1 = new Interop.timespec();
                var t2 = new Interop.timespec();

                // Use nanosleep if interval is higher than 450µs
                t1.tv_sec  = (IntPtr)0;
                t1.tv_nsec = (IntPtr)((long)(millisecondDelay * 1000000) - nanoSleepOffset);

                Interop.nanosleep(ref t1, ref t2);
            }
            else
            {
                while (true)
                {
                    if ((DateTime.UtcNow.Ticks - start) * 0.0001m >= millisecondDelay)
                    {
                        break;
                    }
                }
            }
        }