Option Explicit

Public Declare Sub mouse_event Lib "user32" (ByVal dwFlags As Long, ByVal dx As Long, ByVal dy As Long, ByVal cButtons As Long, ByVal dwExtraInfo As Long)
Public Const MOUSEEVENTF_ABSOLUTE = &H8000 ' absolute move
Public Const MOUSEEVENTF_LEFTDOWN = &H2 ' left button down
Public Const MOUSEEVENTF_LEFTUP = &H4 ' left button up
Public Const MOUSEEVENTF_MIDDLEDOWN = &H20 ' middle button down
Public Const MOUSEEVENTF_MIDDLEUP = &H40 ' middle button up
Public Const MOUSEEVENTF_MOVE = &H1 ' mouse move
Public Const MOUSEEVENTF_RIGHTDOWN = &H8 ' right button down
Public Const MOUSEEVENTF_RIGHTUP = &H10 ' right button up
Public Const MOUSEEVENTF_WHEEL = &H800

Private Sub Command1_Click()
Timer1.Interval = 5000
Timer1.Enabled = True
End Sub

Private Sub Timer1_Timer()
Dim i As Integer
For i = 0 To 100
DoEvents
mouse_event MOUSEEVENTF_WHEEL, 0, 0, 10, 0
Next
For i = 0 To 100
DoEvents
mouse_event MOUSEEVENTF_WHEEL, 0, 0, -10, 0
Next
End Sub