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Composite device: UVC + CDC ACM (serial port), is it possible with FX3 ? | Cypress Semiconductor

Composite device: UVC + CDC ACM (serial port), is it possible with FX3 ?

Summary: 3 Replies, Latest post by tony_1661416 on 16 May 2016 02:58 PM PDT
Verified Answers: 1
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user_2208888's picture
38 posts

Hello, we want to have a composite device, a UVC over bulk end-points along with a CDC-ACM device implementing a simple serial port. The CDC -ACM device doesn't need to interface with any others peripherals of the FX3 but the data must be processed by the FX3 firmware directly. Also the whole device must work as a hi-speed device, super-speed is not mandatory.

My questions are:

- Are there enough enough available endpoints to implement such a composite device ( i.e. FX2 doesn't have enough ) in hi-speed mode ?

- Any precautions that needs to be taken while assigning the end-points and building the device descriptor to insure compatibility with Windows OS, I knew for example that doing a composite CDC-ACM device with FX2 was needing a special INI file to have both COM ports recognized ?

- Anybody knows of an easy way to build the USB device descriptors for FX3, something like GPIF Designer but for device descriptors, even some Phyton scripts will be nice, especially for composite device specifying manually the descriptor is extremly error prone and cumbersome ?


 Any help on those toppics is very appreciated, thank you and best regards, M.C.



rskv's picture
Cypress Employee
1134 posts

 Hi M.C,


We have these two examples separately in the FX3 SDK examples.

Please look for "UsbUart" and "USBVideoClassBulk".

For UVC implementation using FX3, I recommend you to go through the following application note:

AN75779 - How to Implement an Image Sensor Interface with EZ-USB® FX3™ in a USB Video Class (UVC) Framework


You still need to use  an .inf file to add the VID and PID of your device to bind to a com port driver.

Currently we don't have any utility that can generate the USB descriptors. We need to do manually.

Please let me know if you have any more questions regarding this.



Sai Krishna.

user_2208888's picture
38 posts

Hello and thank you for the previous answer, I was wondering if there are any examples in the SDK or associated with an AN about implementation of a composite (multi-function) device, prefferably with IAD ?

 Many thanks


tony_1661416's picture
4 posts

MCM, were you able to create your composite device driver??

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