public partial class Clock : UserControl
	{
        public static DependencyProperty HourProperty = DependencyProperty.Register("Hour", typeof(int), typeof(Clock), new PropertyMetadata((int)0, OnTimeChanged));
        public static DependencyProperty MinuteProperty = DependencyProperty.Register("Minute", typeof(int), typeof(Clock), new PropertyMetadata((int)0, OnTimeChanged));
        public static readonly RoutedEvent TimeChangedEvent=EventManager.RegisterRoutedEvent("TimeChanged", RoutingStrategy.Bubble, typeof(RoutedPropertyChangedEventHandler<int>), typeof(Clock));

        public Clock()
        {
            this.InitializeComponent();
        }

        public int Hour
        {
            get { return (int) GetValue(HourProperty);}
            set { SetValue(HourProperty, value); }
        }
        public int Minute
        {
            get { return (int)GetValue(MinuteProperty); }
            set { SetValue(MinuteProperty, value); }
        }

        private static void OnTimeChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
        {
            Clock clock = (Clock)sender;
            int newTime;
            int oldTime = (int)e.OldValue;
            if (e.Property==HourProperty)
            {
                //...
                clock.Hour =(int)e.NewValue;
                //...
                newTime = clock.Hour;
                RoutedPropertyChangedEventArgs<int> args = new RoutedPropertyChangedEventArgs<int>(oldTime, newTime);
                args.RoutedEvent = Clock.TimeChangedEvent;
                clock.RaiseEvent(args);
            }
            if (e.Property == MinuteProperty)
            {
              //аналогично
            }
        }
        public event RoutedPropertyChangedEventHandler<int> TimeChanged
        {
            add { AddHandler(TimeChangedEvent, value);}
            remove { RemoveHandler(TimeChangedEvent, value);}
        }

        private void ButtonHUp_Click(object sender, System.Windows.RoutedEventArgs e)
        {
           Hour++;
        }
        //...

<My:Clock Minute="{Binding Path=StartTime.Minute}" Hour="{Binding Path=StartTime.Hour}"/>

  public class TimeStruct : INotifyImplementation
    {
        private int hour;
        public int Hour
        {
            get { return this.hour; }
            set
            {
                if (this.hour != value)
                {
                    this.hour = value;
                    OnPropertyChanged("Hour");
                }
            }
        }
        private int minute;
        public int Minute
        {
            get { return this.minute; }
            set
            {
                if (this.minute != value)
                {
                    this.minute = value;
                    OnPropertyChanged("Minute");
                }
            }
        }

public static DependencyProperty HourProperty = DependencyProperty.Register("Hour", typeof(int), typeof(Clock), new PropertyMetadata((int)0, OnTimeChanged));

public static DependencyProperty HourProperty = DependencyProperty.Register("Hour", typeof(int), typeof(Clock), new FrameworkPropertyMetadata((int)0, FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, OnTimeChanged));