2 Replies Latest reply on Feb 19, 2018 2:23 AM by tizi_297541

    CyUsb232 SEH exception

      I'm using the CYUSBS232 USB-UART LP Reference Design Kit (Windows 7 64 bit, cyusbserial version and sometimes get an SEH exception:


      SEH exception EXCEPTION_ACCESS_VIOLATION at address 0x000007FEFA28AAFB inside cyusbserial.dll loaded at base address 0x000007FEFA280000


      I have a feeling that this is triggered somehow by using event notifications, i.e. a method registered with CySetEventNotification. My event handler just prints something to the console while the main thread is doing serial communication on the device. I have noted that the event notification callback is done in a separate thread.


      Is this a known issue? Is there anything I can do about it? Can I expect an update to the device driver and/or DLL anytime soon?


      Kind regards,

      Timon Zijnge

        • 1. Re: CyUsb232 SEH exception

          Hello Timon,


          Please let us know the USB Serial driver version and the firmware version that you are using.

          Also, update the cyusbserial.dll file version to, which can be obtained from the USB-Serial SDK. Please refer to the below location for USB-Serial SDK.

          USB-Serial Software Development Kit | Cypress Semiconductor


          Best regards,

          Srinath S

          • 2. Re: CyUsb232 SEH exception

            Hi Srinath,


            We are using the DLL files from the SDK folder 'library\cyusbserial' with version It seems to me that these files are meant for distribution, as it is available for x86 and x64 and comes with a header file. I have also found the DLL with version you are referring to, but it seems to be a 32-bit build. As we have a 64 bit application, we cannot use it. Our application fails to start when we substitute for

            I am not entirely sure what you mean by 'USB Serial driver version' and the 'firmware version', but I looked up the following

            • driver version in windows device manager under 'Universal Serial Bus controllers':
            • target version in serial configuration utility:


            Sorry for my late response. I was expecting an email notification for any responses, but I didn't get one or I missed it.


            Kind Regards,