Alexander Carôt wrote: > 3.) Has anyone information about the communication layer USB-audio puts on > top of the PCI-bus and how much delay it takes ?
USB data is sent in packets; time is divided into one-millisecond frames. USB audio sends the data for one millisecond in one packet (per frame). The host controller does not (and can not) guarantee when in a frame the packet is sent, so a packet that is to be sent in frame N must be prepared by the driver during frame N-1 (or earlier) and will be played by the device in frame N+1. For capturing, the situation is the same. > In other words : Can a USB device ever reach latencies like PCI-devices ? No. Clemens ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://sel.as-us.falkag.net/sel?cmd=lnk&kid3432&bid#0486&dat1642 _______________________________________________ Alsa-user mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/alsa-user
