beautypg.com

Avago Technologies LSI53C1010R User Manual

Page 191

background image

SCSI Registers

4-73

Version 2.2

Copyright © 2000–2003 by LSI Logic Corporation. All rights reserved.

SBMC

SCSI Bus Mode Change

4

Setting this bit allows the LSI53C1010R to generate an
interrupt when the DIFFSENS pin detects a change in
voltage level that indicates the SCSI bus has changed
between SE, LVD, or HVD modes. For example, when
this bit is cleared and the SCSI bus changes modes, IRQ/
does not assert and the SIP bit in the Interrupt Status
Zero (ISTAT0) register is not set. However, bit 4 in the

SCSI Interrupt Status One (SIST1)

register is set. Setting

this bit allows the interrupt to occur.

R

Reserved

3

STO

Selection or Reselection Time-out

2

This bit is set when the SCSI device which the
LSI53C1010R SCSI function is attempting to select or
reselect does not respond within the programmed
time-out period. Refer to the description of the

SCSI Timer Zero (STIME0)

register, bits [3:0], for details

on the time-out timer.

GEN

General Purpose Timer Expired

1

This bit is set when the general purpose timer expires.
The time measured is the time between enabling and
disabling of the timer. Refer to the description of the

SCSI Timer One (STIME1)

register, bits [3:0], for details

on the general purpose timer.

HTH

Handshake-to-Handshake Timer Expired

0

This bit is set when the handshake-to-handshake timer
expires. The time measured is the SCSI
Request-to-Request (target) or
Acknowledge-to-Acknowledge (initiator) period. Refer to
the description of the

SCSI Timer Zero (STIME0)

register,

bits [7:4], for details on the handshake-to-handshake timer.