Timed Sub

[Paleo]

Hi Ken sorry for not posting it here in the first place:

Here is it:

At This_Workbook

Private Sub Workbook_SheetActivate(ByVal Sh As Object)
    Call Timer
End Sub

Private Sub Workbook_SheetSelectionChange(ByVal Sh As Object, ByVal Target As Range)
    Call Timer
End Sub

At Module1

Public vartimer As Variant
    
Sub Timer()
    On Error Resume Next
    Application.OnTime earliesttime:=vartimer, _
       procedure:="Fecha", schedule:=False
    On Error GoTo 0
vartimer = Format(Now + TimeSerial(0, 30, 0), "hh:mm:ss")
    If vartimer = "" Then Exit Sub
    Application.OnTime TimeValue(vartimer), "Fecha"
End Sub