Hello Devendra, If USBD creates such an API, then USBAudio will definitely try to take advantage of it. At this point I cannot tell you when or if that may be. Even if such an interface is created it would still be useful only to Adaptive and Sync endpoints since it would be nearly impossible to continually adjust the transfer descriptors on the exposed transfer buffer to account for feedback for Async. DJ This posting is provided "AS IS" with no warranties, and confers no rights. -----Original Message----- From: wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of BlazeAudio Developer Sent: Wednesday, May 14, 2003 10:57 AM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] Re: USB Audio synch. mechanism Hi DJ, That makes a lot of sense! Also, is the new usbaudio.sys going to use WaveRT port - would be possible ifUSBD provided a cyclic DMA based mechanism (like the 1394.sys)? Thanks. Devendra. At 09:37 AM 5/14/2003, DJ Sisolak wrote: Hello Devendra, The error with async endpoints has to do with the timeliness of the updating of the sample rate based on the data from the feedback endpoint. Technically it will work with all OS's back to Win98, but only recently have I fixed the timing. Thanks, DJ Sisolak Microsoft Corp. This posting is provided "AS IS" with no warranties, and confers no rights. -----Original Message----- From: wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx[1]] On Behalf Of BlazeAudio Developer Sent: Tuesday, May 13, 2003 7:11 PM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] USB Audio synch. mechanism [OOPS! I'd posted this message with incorrect subject!] The "USB Audio and Windows" whitepaper (available from http://www.microsoft.com/whdc/hwdev/tech/audio/USBaud.mspx[1[2]]) says: "Starting with Windows 98, Usbaudio.sys supported the adaptive and synchronous endpoints, but it did not implement the asynchronous endpoint correctly. Full support for asynchronous endpoints in Usbaudio.sys is plannedfor Windows Longhorn." However, I have implemented async. isoch. synch. mechanism on two different devices - and it has worked perfectly - starting from Windows 98 SE. What's not correct about the implementation? Thanks. Devendra.=3D20 --- Links --- 1 http://www.microsoft.com/whdc/hwdev/tech/audio/USBaud.mspx[3] ****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx[4] Subscribe: =3D mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=3D3Dsubscribe[5] Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=3D3Dunsubscribe[6] Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx[7] URL to WDMAUDIODEV page: http://www.wdmaudiodev.de/[8] ****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx[9] Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=3Dsubscribe[10] Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=3Dunsubscribe[11] Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx[12] URL to WDMAUDIODEV page: http://www.wdmaudiodev.de/[13]=20 --- Links --- 1 mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx 2 http://www.microsoft.com/whdc/hwdev/tech/audio/USBaud.mspx%5B1 3 http://www.microsoft.com/whdc/hwdev/tech/audio/USBaud.mspx 4 mailto:wdmaudiodev@xxxxxxxxxxxxx 5 mailto:wdmaudiodev-request@xxxxxxxxxxxxx%3Fsubject=3D3Dsubscribe 6 mailto:wdmaudiodev-request@xxxxxxxxxxxxx%3Fsubject=3D3Dunsubscribe 7 mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx 8 http://www.wdmaudiodev.de/ 9 mailto:wdmaudiodev@xxxxxxxxxxxxx 10 mailto:wdmaudiodev-request@xxxxxxxxxxxxx%3Fsubject=3Dsubscribe 11 mailto:wdmaudiodev-request@xxxxxxxxxxxxx%3Fsubject=3Dunsubscribe 12 mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx 13 http://www.wdmaudiodev.de/ ****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: = mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=3Dsubscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=3Dunsubscribe 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/