Private Sub CommandButton1_Click()
Const max = 0.75 'durée max en seconde avec ou non fraction de seconde
Dim dat0 As Date, sec0 As Double, duree As Double, old
dat0 = Date: sec0 = Timer: old = Me.BackColor: Me.BackColor = RGB(0, 255, 0)
Do: DoEvents: duree = 86400 * (Date - dat0) + Timer - sec0: Loop Until duree > max
Me.BackColor = old
End Sub