What scsi phase should a target enter ...?

Luu, Trung Trung_Luu at adaptec.com
Thu Jun 13 12:47:24 PDT 2002

* From the T10 Reflector (t10 at t10.org), posted by:
* "Luu, Trung" <Trung_Luu at adaptec.com>

In section of SPI-4 revision 9, the specs states that "... If the
first message received by the
SCSI target port during the MESSAGE OUT phase is not a TARGET RESET message
or PPR message
the SCSI target port shall change to a MESSAGE IN phase and issue a MESSAGE
REJECT message
then originate WDTR negotiation (see with the TRANSFER WIDTH
EXPONENT field set to 00h."

In Section, figure 18, column 3. SCSI target port response with
WDTR OUT with legal values,
states that " ... The SCSI target port shall ... , abort all tasks to SCSI
initiator device if IU_REQ was
changed, and originate an SDTR IN."

And in Section, table 10 mentions the bus phases resulting from
IU_REQ changes.
If I'm understanding the specs correctly, it states that If an IU_REQ value
goes from 1 to 0 because of
WDTR negotiation, then the scsi bus phase following WDTR messages should be
BUS FREE phase.

My question is what scsi phase should a target enter right after a
completion of WDTR messages
if IU_REQ was changed i.e. from 1 to 0.? 

Thank you in advance,
-Trung Luu
* For T10 Reflector information, send a message with
* 'info t10' (no quotes) in the message body to majordomo at t10.org

More information about the T10 mailing list