5 Replies Latest reply on Jul 10, 2020 6:14 AM by RiBi_4316346

    CX3-UVC device disconnects from Amcap when streaming starts



      I created a CX3 project to stream video from a MIPI image sensor to a Windows 10 PC using UVC.

      The board mounting the sensor and the CX3 is a custom design.

      I tried to verify the streaming using Amcap: the streaming works well, but only if I use a USB3.0 hub between the CX3 cable and the USB SS port of the PC.

      If I connect directly the CX3 cable to the port there is a strange behaviour: I still can select the CX3-UVC device from the available devices in Amcap, but as soon as I make the sensor start streaming (using a button on the PCB) the streaming in Amcap starts and then fails after a few frames (giving the typical sound of a usb device disconnected).

      After this, the CX3-UVC device is not re-enumerated I think, the device is still visible in device manager and in the Amcap available devices: if I select it again in Amcap and repeat the procedure the behaviour is the same as before.


      Here is how I obtained the firmware:

      I started from a blank project (File->New->Project->Cypress->CX3 Configuration Project), then I modified the cx3config.cycx file according to the sensor video specifications and I generated all the project files.

      Then I wrote all the code needed to program our sensor, that is called from the main project file cycx3_uvc.c.

      Inside cycx3_uvc.c I didn't change anything from the original file generated using cx3config.cycx.


      Can you help me understand what is the issue?

      I attach my cycx3_uvc.c file and uart logs obtained in both cases (with and without usb hub) in which I omitted all the initial configuration debug prints.


      Thank you,