data IU exception handling

Sriram Srinivasan srirams at
Wed Aug 16 13:32:13 PDT 2000

* From the T10 Reflector (t10 at, posted by:
* Sriram Srinivasan <srirams at>
    I have a question on data IU exception handling:

    In (SPI4-rev0) paragraph 4 it states:

    "If the information unit that failed was not a SPI status information unit
and the message received from the initiator was an INITIATOR DETECTED ERROR
message then the target <SHALL> send a SPI L_Q/SPI status information unit 
to the initiator with a CHECK CONDITION status and a sense key set to ABORTED
COMMAND and ..."

    Paragraph 6 of 14.1 states:

    "The initiator shall save the data pointers as soon as the last byte of 
last iuCRC for a SPI information unit is transferred.  The save <SHALL> occur
even if the initiator detects an error in the SPI data information unit.  If a
target retries an operation it <SHALL> send a MODIFY DATA POINTERS message 
request that the SPI data information unit be transferred again."

    Doesn't the first one (para 4 in say that tha target cannot 
the command ('coz he sent the ABORTED COMMAND sense key)?  In this case, the
initiator would probably resend the whole command again.  But para. 6 of 14.1
seems to imply that targets can retry the SPI data IU and mandates that the
MODIFY DATA POINTES message be sent prior to such a retry.  These seem to
contradict each other.  The same wordings are present in SPI-3 as well.

   Is there a bigger thing that I'm missing here?  Please let me know.


  Sriram Srinivasan                       Sriram.Srinivasan at
  ASIC Design Engineer, LSI Logic,
  2001 Danfield Ct., 				Phone: 970-206-5847
  Fort Collins, CO 80525				FAX  : 970-206-5244

* For T10 Reflector information, send a message with
* 'info t10' (no quotes) in the message body to majordomo at

More information about the T10 mailing list