X3T9.2/92-117
 
    MEMORANDUM    --    18 May 1992
 
    TO:           John Lohmeyer, Chairman, X3T9.2
 
    FROM:         Bill Spence, Chair, SPI WG
 
    SUBJECT:      Fast SCSI Stubs Dimensions and Specifications Format
 
    STUB DIMENSIONS
 
    It has been pointed that the deleterious effects of stub reflections
    become proportionally more damaging as signal pulse widths decrease.
    And the need to minimize stub lengths has been widely proclaimed.
    Accordingly, I submit the following:
 
    Proposal -- Add the following sentence to the the second paragraph
    of 5.2.1 of 91-010R4:  For Fast Synchronous Data Transfer, these
    dimensions should be halved.
 
    FAST SCSI SPECIFICATIONS FORMAT
 
    It is becoming clear that by the time the SPI Standard is a significant
    force, almost all development work will contemplate Fast SCSI operation.
    It thus appears illogical to have the Standard present information in
    a general format and then in a separate place negate it with special
    instructions pertaining to Fast SCSI.  Accordingly, I submit the
    following:
 
    Proposal -- Delete 5.2.3.  Move the length comment to 5.2.1.  Move the
    attenuation comment to 5.2.  Delete the DC Resistance comment, which is
    superceded by wording already in 5.2.  If any other special requirements
    for Fast SCSI exist, place them on equal footing with existing text.