' Time of next update.
Private UpdateTime As Variant
 
Public Sub ScheduleUpdate()
    ' Schedule an update 1 second from now.
    UpdateTime = Now + TimeSerial(0, 0, 1)
    Application.OnTime UpdateTime, "Sheet1.UpdateCells"
End Sub
 
Private Sub Workbook_Deactivate()
'Private Sub Workbook_BeforeClose(Cancel As Boolean)
    ' Clear a previously set update, if any.
    On Error Resume Next
    Application.OnTime UpdateTime, "Sheet1.UpdateCells", , False
End Sub
 
Private Sub Workbook_Activate()
'Private Sub Workbook_Open()
    ' Schedule the first update.
    ScheduleUpdate
End Sub

' Holds cells to be updated, and the update values.
Dim CellsToUpdate As New Dictionary

Private Sub Client_MonitoredItemChanged(ByVal Sender As Variant, ByVal E As OpcLabs_EasyOpcUA.EasyUAMonitoredItemChangedEventArgs)
    ' Store the value in the intermediate dictionary. The cell name is passed to us in the State property.
    Set CellsToUpdate(E.arguments.State) = E.AttributeData.Value
End Sub
 
Public Sub UpdateCells()
    ' Update values that have changed since the last update. The cell names and values are stored in the intermediate dictionary.
    For Each Cell In CellsToUpdate.Keys
        Range(Cell).Value = CellsToUpdate(Cell)
    Next
 
    ' Clear the intermediate dictionary.
    CellsToUpdate.RemoveAll
 
    ' Schedule next update.
    ThisWorkbook.ScheduleUpdate
End Sub

Private Sub Client_MonitoredItemChanged(ByVal Sender As Variant, ByVal E As OpcLabs_EasyOpcUA.EasyUAMonitoredItemChangedEventArgs)
    ' Update the value in the cell. The cell name is passed to us in the State property.
    Range(E.arguments.State).Value = E.AttributeData.Value
End Sub

Private Sub Client_MonitoredItemChanged(ByVal Sender As Variant, ByVal E As OpcLabs_EasyOpcUA.EasyUAMonitoredItemChangedEventArgs)
    ' Schedule an update. The cell name is passed to us in the State property.
    ValueString = """" & Replace(Replace(E.AttributeData.Value, """", """"""), "'", "''") & """"
    Application.OnTime Now, "'Sheet1.UpdateCell """ & E.arguments.State & """, " & ValueString & "'"
End Sub
 
Private Sub UpdateCell(Cell As Variant, Value As Variant)
    ' Update the value in the cell.
    Range(Cell).Value = Value
End Sub