UBF Timeout Function

Lawrence J. Lamers ljlamers at ix.netcom.com
Wed Dec 9 07:16:38 PST 1998

* From the T10 Reflector (t10 at symbios.com), posted by:
* "Lawrence J. Lamers" <ljlamers at ix.netcom.com>
To:     T10 Membership
From:   Lawrence J. Lamers
Subject:        UBF Timeout Function
Date:   Wednesday, December 09, 1998

This proposal adds a UBF timeout field to the Control Mode page. The UBF
timeout field is a sixteen-bit value in one millisecond increments.  A
value of
0000h indicates that the function is disabled.  A value of FFFFh indicates an
unlimited period.   (See also the busy timeout period definition in SPC-2).

This proposal adds a bit to the INQUIRY data to indicate that the device
supports a UBF timeout function.

Note:  The specific bytes/bits location in the Control Mode page and INQUIRY
data are left to the discretion of Ralph

The unexpected bus free timeout is intended to clear the bus in the event of a
bus hang.  The device starts the UBF timeout function on the transition of REQ
and clears it on the transition of ACK.  If the UBF timeout expires without
assertion of ACK the device goes to unexpected bus free.  The existing rules
related to unexpected bus free behavior apply.


Lawrence J. Lamers                     Adaptec, Inc
email:   ljlamers at ieee.org            691 South Milpitas Blvd.
Phone: (408) 578-1709                 Milpitas, CA  95035

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

More information about the T10 mailing list