On Mon, 1 Aug 2011, loody wrote: > sorry for picking this old thread, since the subject is the same. > my question is: > In high speed device and an urb->inerval is less than 8, take 2 or 4 > for example, the number of iso transfer descriptors will be > 1+(span+7)/8. > > But the formula above seems to be used for urb-> interval =1, right? > Why the # of iso transfer descriptors not to be span/interval but 1+(span+7)/8? Because each iTD provides information for an entire frame, i.e., 8 microframes. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
