' Declarations:
Private Declare Function SetTimer Lib "user32" (ByVal hwnd As Long, ByVal nIDEvent As Long, _
    ByVal uElapse As Long, ByVal lpTimerFunc As Long) As Long
Private Declare Function KillTimer Lib "user32" (ByVal hwnd As Long, ByVal nIDEvent As Long) As Long
    Private mlngTimerID As Long

' Module code:
Public Sub StartTimer(lngInterval As Long)
    mlngTimerID = SetTimer(0, 0, lngInterval, AddressOf TimerCallBack)
End Sub

Public Sub TimerCallBack(ByVal hwnd As Long, ByVal uMsg As Long, _
    ByVal idEvent As Long, ByVal dwTime As Long)
    ' Do Something Here
End Sub

Public Sub StopTimer()
    KillTimer 0, mlngTimerID
End Sub