Private Sub tmrTrigger_Timer()
    ' See if it time for the event.
    If Timer >= NextEventTime Then
        ' Process the event.
        lblEventTime.Caption = Format$(DateAdd("s", _
            INTERVAL_SECONDS, Time))

        ' Set the new event time.
        NextEventTime = NextEventTime + INTERVAL_SECONDS
    End If

    ' Set the timer's interval.
    If NextEventTime - Timer < 60 Then
        tmrTrigger.Interval = (NextEventTime - Timer) * 1000
    Else
        tmrTrigger.Interval = 60000
    End If
End Sub