Sub SetAlarm() 
Application.OnTime 0.625, "MostrarAlarma"
End Sub

Sub DisplayAlarm() 
    Application.Speech.Speak ("Hey levántate")
    MsgBox "Es hora de tomarse un descanso"
End Sub
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Sub MostrarAlarma()
    Application.OnTime TimeValue("3:00:00 pm"), "MostrarAlarma"
End Sub
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Sub MostrarAlarma() 
    Application.OnTime Now + TimeValue(“00:20:00”), "MostrarAlarma"
End Sub
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Sub DisplayAlarm() 
    Application.OnTime DateValue("11/10/2019 10:00 am"), _
	"DisplayAlarm"
End Sub
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Dim NextTick As Date
Sub UpdateClock()
        'Actualiza la celda A1 con la hora actual
        ThisWorkbook.Sheets(1).Range("A1") = Time
        'Configura el próximo evento dentro de cinco segundos
        NextTick = Now + TimeValue("00:00:05")
        Application.OnTime NextTick, "ActualizarReloj"
    End Sub

Sub StopClock()
'   Cancela el evento OnTime (detiene el reloj)
    On Error Resume Next
    Application.OnTime NextTick, “ActualizarReloj”, , False
End Sub

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Call StopClock

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Sub Setup_OnKey() 
    Application.OnKey "{PgDn}", "PgDn_Sub"
    Application.OnKey "{PgUp}", "PgUp_Sub"
End Sub

Sub PgDn_Sub() 
    On Error Resume Next 
    ActiveCell.Offset(1, 0).Activate
End Sub

Sub PgUp_Sub() 
On Error Resume Next 
    ActiveCell.Offset(-1, 0).Activate
End Sub
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Sub Cancel_OnKey() 
    Application.OnKey "{PgDn}"
    Application.OnKey "{PgUp}"
End Sub
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Application.OnKey "%{F4}", ""
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