If the USB Module could be used to play and record wav file?

[freecomm]

Greate work!

I am new to this forum.  I think this website is a greate DIY project.  I want to know  If the USB Module could be used to play and record wav file? 

Thanks.

David

[moebius]

Noo..

It's "only" a midi interface. ;D

There are some USB audio circuits to be found on the internet - but those should really be considered as surface mount component soldering practice, with current audio interface prices.. I mean you'll probably end up losing money by building one yourself.

Bye, Moebius

[freecomm]

Thanks.Moebius.  ;D

I know little about the USB classes. But I think if we modify the fireware, it  maybe a wav interface then.

[Lall]

Hi Freecomm,

Indeed, by modifying the firmware running on the EZ-USB, you can certainly make it a wav reader/player. I'm using the very same chip as a HID device, the black magic to change skin is mainly in the descriptors.

There are however two things you need to consider:

1) you need to get the samples in/out and therefore you need a DAC/ADC that can interface in a nice way with the EZ-USB. You should look at how they are implementing what they call Fast transfer mode or something of that kind; it's actually a kind of FIFO that can help you speed up considerably the transfer duration.

2) you need to get a firmware up and running with audio class functionality. I've quickly looked at the spec from the USB site some time ago and that's quite indigestible. Finding a good sample on the web would be very much appreciated I presume. If someone knows about one, I'm interested as well  ;)

Best regards,

Lall