Hi I have this info about DLL using (functions): http://www.silabs.com/Support%20Documents/TechnicalDocs/an117.pdf How to using in AutoIt? example from this pdf (see above link): =========================================================================== 3. Communications Functions The following communication functions are available for use in the Interface Utilities DLL. Connect() - Connects to a target C8051Fxxx device using a Serial Adapter. Disconnect() - Disconnects from a target C8051Fx