FX3: Combine UVC demo (AN75779) and USB - UART Bridge Example

[LeGa_3963206]

Hi,

I want to implement two features in my FX3:

     - UVC device

     - USB-UART bridge

so that they exists simultaneously (within same configuration in terms of descriptors)

I successfully merged all required functions, but got stucked with descriptors. Both modes work fine separately but do not work together - Windows says "Invalid USB configuration descriptor"

So my questions are:

1) Is it possible at all?

2) Does CyU3PUsbSetDesc supports non zero desc_index for desc_type other than CY_U3P_USB_SET_STRING_DESCR? Comments says it doesn't but some answers on this forum states that is does?

3) How to number interfaces within the same config descriptor if it contains "interface association descriptor" with several interfaces inside?

P.S. I'm attaching my SS,HS and FS configuration descriptors.

Thanks

[JayakrishnaT_76 · Accepted solution]

Hello,

Please find my comments to your questions below:

>>Is it possible at all?

Yes, it is possible. Please refer to the following thread which describes how to add CDC interface to UVC firmware.

Can EZ-USB FX3 enumerate serial devices and video and video devices at the same time?

>> Does CyU3PUsbSetDesc supports non zero desc_index for desc_type other than CY_U3P_USB_SET_STRING_DESCR? Comments says it doesn't but some answers on this forum states that is does?

Inside the definition of CyU3PUsbSetDesc, desc_index is used only used for the CY_U3P_USB_SET_STRING_DESCR (string descriptor). For all other descriptors, this parameter is not used inside the definition of CyU3UsbSetDesc. So even if you pass a non zero desc_index, it will not make any difference.

>>How to number interfaces within the same config descriptor if it contains "interface association descriptor" with several interfaces inside?

Please find the following KBA which describes how to add CDC interface to FX3 firmware. The link to the KBA is given below:

Adding Communication Device Class Interface to FX3 Firmware - KBA229099

Best Regards,

Jayakrishna