Mr. Tsai, If you read the following page http://msdn.microsoft.com/library/default.asp?url=/library/en-us/stream/hh/stream/pcdesign_9y1z.asp, it states that USB Audio devices use USBAudio.sys and not PortCls.sys. The diagram on the page should help clarify what Microsoft had in mind. Regards, -Akos Horvath. ----- Original Message ----- From: "Tdtsai" <tdtsai@xxxxxxxxxxxxxxxxxx> To: <wdmaudiodev@xxxxxxxxxxxxx> Sent: Wednesday, July 16, 2003 7:09 PM Subject: [wdmaudiodev] Re: Usb Audio Driver > Hi Bart > I don't find the DDK say we can't use PortCls to implement USB Audio Driver. > DDK say "The PortCls framework might also be useful for constructing drivers > for audio device on other hardware buses or for software only device.". So > PortCls may not wrong way to implement USB Audio Driver. > > BR, > Tzung-Dar Tsai > >According to Microsoft you are not supposed to >use the PortCls for USB > devices. > >The DDK says you should comply with the USB >sound spec. so Windows will > use its > >internal drivers. The fact that this results in >a high latency (Kmixer) > which > >makes the device unusable is not an issue for MS. > >The only 'proper' way would be to write you're >own KS driver, which is a > lot > >of work. > > > >Regards, > > Bart > >****************** > > > > ________________________________________________ > > ****************** > > WDMAUDIODEV addresses: > Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx > Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe > Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe > Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx > > URL to WDMAUDIODEV page: > http://www.wdmaudiodev.de/ ****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.de/
