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µVISION DEBUGGER: USB To Serial Converter Does Not Work

Information in this article applies to:

  • µVision All Versions


Some laptop computers do not have a COM port (which is required to use Monitor-51, Monitor-166, Monitor-251 or ISD51 for target debugging). A USB to COM port converter may be used, but the timing and driver reactions of such devices are sometimes different than standard COM ports.

Problems have been reported with the Targus USB port extender PA090. µVision opens a Connection to Target System lost error dialog when the debugger starts.


The driver for this device does not support all of the Windows API calls which are used by the µVision debugger.


Download the latest driver from Targus Website. This problem may be solved in a newer driver. If the problem is not solved, you cannot use this device.

Last Reviewed: Tuesday, February 23, 2021

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