Re: usb continuous output frequency format
Re: usb continuous output frequency format
- Subject: Re: usb continuous output frequency format
- From: Jeff Moore <email@hidden>
- Date: Mon, 6 Jan 2003 11:47:56 -0800
Note also that the IOAudio family allows you to specify continuous
ranges for the sample rate. I'm not up on the specific call you have to
make in your driver, but the HAL should be exporting the ranges
described in the available formats in the registry entries for the
given IOAudioStream.
On Thursday, December 26, 2002, at 01:01 PM, Mark Ketilson wrote:
Thanks for the info Jeff,
The reason I was hoping to have the output frequency change is for
SPDIF transfers. I will try to add discrete frequencies as Shaun and
Kevin suggested in later messages and see if that will unlock my
device capabilities.
Thanks for the help,
Mark
On Wednesday, December 25, 2002, at 12:00 AM,
email@hidden wrote:
Date: Tue, 24 Dec 2002 10:04:26 -0800
Subject: Re: usb continuous output frequency format
From: Jeff Moore <email@hidden>
To: CoreAudio API <email@hidden>
The HAL provides the API for discovering and changing the stream
format
of your device. The properties kAudioDevicePropertyNominalSampleRate
and kAudioDevicePropertyAvailableNominalSampleRates are apropos here.
The fact that most apps just leave the device set to one sample rate
and do software rate conversion is pretty much common practice. There
isn't anything your device can do to force them to change the format
when they are happy with that arrangement.
On Monday, December 23, 2002, at 03:58 PM, Mark Ketilson wrote:
I have a USB device with an output channel that has continuous
frequency capability. It supports frequencies in a certain range and
returns that range. {4990, 55010} The device is set to 44.1 kHz as
the
default.
The problem I'm having is that no audio program changes the frequency
of my device when I play files of a frequency other than 44.1kHz.
I'm
wondering if there is a suggested method to add this functionality to
my device and why audio programs aren't able to recognize the device
capabilities.
--
Jeff Moore
Core Audio
Apple
--__--__--
_______________________________________________
coreaudio-api mailing list | email@hidden
Help/Unsubscribe/Archives:
http://www.lists.apple.com/mailman/listinfo/coreaudio-api
Do not post admin requests to the list. They will be ignored.
--
Jeff Moore
Core Audio
Apple
_______________________________________________
coreaudio-api mailing list | email@hidden
Help/Unsubscribe/Archives:
http://www.lists.apple.com/mailman/listinfo/coreaudio-api
Do not post admin requests to the list. They will be ignored.