X3T9.2/90-036




March 1, 1990

Mr. Jeffrey Stai
Western Digital Corp.
2445 McCabe Way
Irvine, CA 92714

Subject: Response to BSR X3.131-198x (SCSI-2) Public Review Comment #3

Dear Mr. Stai,

Thank you for your public comment (X3T9.2/89-140) concerning the SCSI-2 draft 
proposed standard.  While the X3T9.2 committee generally agrees with your 
position that in the future the SCSI-3 16-bit "P" cable solution will likely 
be more widely implemented than the SCSI-2 16-bit "A/B" cable solution, the 
committee feels that the "P" cable is not sufficiently stable at this time to 
include it in SCSI-2.  In particular, the method by which a "P" cable system 
may be expanded to 32 bits needs more study.  Furthermore, it would be 
inappropriate to remove documentation of the "B" cable when some products have 
already implemented the "B" cable.

X3T9.2 plans to have a single-connector 16-bit solution in SCSI-3 including 
a method of expanding to 32 bits.  A draft working document is expected later 
this year.

In order to alert SCSI-2 implementors of the potential for changes in this 
area, a note will be included in SCSI-2 saying that X3T9.2 is documenting an 
alternative 16-bit single-cable solution and an alternative 32-bit solution 
and expects to be able to remove the "B" cable in a subsequent version of 
SCSI.

Please send a written statement to the X3 Secretariat (Attn: Lynn Barra) 
within fifteen working days saying whether you accept or reject this response.  
If you do not respond within fifteen working days, the Secretariat will assume 
that you have withdrawn the comment.

Sincerely Yours,


Del Shoemaker, X3T9 Chairman

cc: L. Barra, X3 Secretariat
    J. Lohmeyer, X3T9.2 Chairman
    J. Ryland, SPARC Liaison