Thread safe calls to windows forms controls

To avoid this error, you'll need to marshal any changes to controls back to the UI thread which created them.

To do this, first add this Sub to your Form, containing the line to be executed:

Sub tReading_Update()

Me.tReading.Text = Format(reading, "#0.00000")

End Sub

Now, where the error occurred, replace the offending line with these lines:

Dim mi As MethodInvoker = AddressOf tReading_Update

Me.Invoke(mi)

If it doesn't work or only works intermittently, then replace the last line with the asynchronous version:

Me.BeginInvoke(mi)