Public Class frmMain
    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles tmrTick.Tick

        If nudSeconds.Value <> 0 Then
            nudSeconds.Value -= 1
            lblTest.Text = nudHours.Value & ":" & nudMinutes.Value & ":" & nudSeconds.Value
        Else
            If nudMinutes.Value <> 0 Then
                nudMinutes.Value -= 1
                nudSeconds.Value = 59
            Else

                If nudHours.Value <> 0 Then
                    nudHours.Value -= 1
                    nudMinutes.Value = 59
                    nudSeconds.Value = 59
                Else
                    tmrTick.Enabled = False
                    'The code below this line activates when the timer hits zero
                    Beep()
                    MsgBox("Time is up")
                End If
            End If
        End If

    End Sub

    Private Sub btnStart_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnStart.Click
        If tmrTick.Enabled = True Then
            tmrTick.Enabled = False
            btnStart.Text = "Start"

        ElseIf tmrTick.Enabled = False Then
            tmrTick.Enabled = True
            btnStart.Text = "Pause"
        End If
    End Sub

    Private Sub btnReset_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnReset.Click
        nudHours.Value = 0
        nudMinutes.Value = 0
        nudSeconds.Value = 0
        tmrTick.Enabled = False
    End Sub

End Class