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Questions about Processor Expert settings about a USB audio project

Question asked by Winston Shi on Feb 12, 2014
Latest reply on Feb 27, 2015 by Marek Neuzil

Hello,

 

I'm doing a project related to USB audio. My tool chain is CodeWarrior 10.5 + Processor Expert 10.3 + USB Stack 4.1.1.

The USB audio topology is as follows,

 

USB_Audio_topology.GIF.gif

 

The MCU I'm using is MK20FN1M0VLQ12.

 

Question 1:  When selecting this MCU as the CPU in the project, I cannot find the USB_AUDIO_CLASS in the Components Library unless I change the filter setting.

USB_Audio_pe1.GIF.gif

 

If I switch off the filter, then the USB_AUDIO_CLASS appears. Does this mean the USB Stack 4.1.1 doesn't support MK20FN1M0VLQ12?

 

Question 2: When I change the settings in P&E, I cannot change the interface settings.

USB_Audio_pe2.GIF.gif

As the snapshot above, the interface is 3, what I expected is that Interface 0 is the control interface, Interface 1 is the Microphone, Interface 2 is the Speaker.

So, Interface 1 is expected to have an Isochronous In Endpoint, I want to assign EP1 to it, Interface 2: Isochronous Out, EP2.

But P&E don't allow me to change the settings, the Endpoints lists of Interface 1 and Interface 2 are both gray color, unchangeable, I don't know why, can somebody tell me why?

 

My email is winston.swh@gmail.com, thanks!

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