PORTS Forum

Ports and Interfaces => USB => Topic started by: erdmann on December 23, 2014, 04:32:05 pm

Title: CBI-I and UFI: completion interrupt lacking sense key
Post by: erdmann on December 23, 2014, 04:32:05 pm

The CBI protocol spec says that if UFI is used as the command set that the 2 Bytes of the command completion Interrupt message contain the Additional Sense Code and the Additional Sense Code Modifer.
That looks like it is unnecessary to issue the "Request Sense" command to get the sense info (in case of error). However, the Sense Key itself is not returned which to me is the MAIN piece of Information (error or no error) !!!
Does that mean I still need to issue the "request sense" command to get the full Information ? Is it an ERROR to issue the "request sense" command under this condition ?

Title: Re: CBI-I and UFI: completion interrupt lacking sense key
Post by: Jan Axelson on December 24, 2014, 08:14:11 am

I believe a mass-storage host can issue REQUEST SENSE at any time.