On Wed, 21 Apr 2010, Luben Tuikov wrote: > The Sector Count field in the ATA PASS-THROUGH (12) or (16) CDB > should be set appropriately by the Application Client as the neither > the SAT bridge nor the SATA transport will interpret the ATA Command > byte. Thus, for IDENTIFY (PACKET) DEVICE the Application Client > should set it to 1. > > Why do you say that 1 is the appropriate value? In the ATA-5 spec > (which is the most recent version I have) Sector Count is listed as > "na" for IDENTIFY DEVICE, which means that the content of that field is > not applicable to this particular command. Hence the value shouldn't > matter. > > It is needed by the transport protocol(s). I don't understand; can you explain more fully? Which transport protocol(s) need to use the Sector Count? The USB transport protocol doesn't; it encodes the transfer length in a wrapper. The bridge chip should interpret the wrapper instead of looking inside the SAT command. 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
