Re: Audio Sources Types
Re: Audio Sources Types
- Subject: Re: Audio Sources Types
- From: Jeff Moore <email@hidden>
- Date: Tue, 11 Dec 2001 17:02:57 -0800
on 12/11/01 4:19 PM, RolandCorp R&D <email@hidden> wrote:
>
> No there is no way to tell whether the port on a device is digital or
>
> analog. Many transport layers, particularly USB (and probably FireWire too
>
> since it hews closely to the USB Audio spec, but I don't know for sure),
>
> don't provide this information.
>
>
Section 3.5.1 and Section 3.5.2 of the "Universal Serial Bus Device Class
>
Definition for Audio Devices" describe the functions of Input and Output
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Terminals (ports).
>
>
The specification called "Universal Serial Bus Device Class Definition for
>
Terminal Types" further define how the descriptor of a USB audio device
>
reports the type of input or output terminal (line, mic, speaker, SPDIF, CD
>
player, etc.)
>
>
Documents online at:
>
http://www.usb.org/developers/devclass_docs.html
>
>
Isn't this what you need?
It would be, but my admittedly small perusal of devices didn't turn up a
single device that supported that information. I didn't have my UA-3 on hand
(it's at home in my studio) to look at, though =)
Like I said, I'm not against the idea of exporting the info when it's there
(I have an bug written up for this issue), it's just that so few devices
support it, it would be a dicey proposition to rely on such a feature.
--
Jeff Moore
Core Audio
Apple