Scsi interrupt status one (sist1), Scsi, Interrupt status one (sist1) – Avago Technologies LSI53C895A User Manual

Page 188: Scsi interrupt, Status one (sist1), Scsi interrupt status one, Sist1), Register: 0x43

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4-80

Registers

register) must be set for this bit to become active. The
LSI53C895A always generates parity when sending SCSI
data.

Register: 0x43

SCSI Interrupt Status One (SIST1)
Read Only

Reading the SIST1 register returns the status of the various interrupt
conditions, whether they are enabled in the

SCSI Interrupt Enable One

(SIEN1)

register or not. Each bit that is set indicates an occurrence of

the corresponding condition.

Reading the SIST1 clears the interrupt condition.

R

Reserved

[7:5]

SBMC

SCSI Bus Mode Change

4

This bit is set when the DIFFSENS pin detects a change
in voltage level that indicates the SCSI bus has switched
between SE, LVD or HVD modes.

R

Reserved

3

STO

Selection or Reselection Time-out

2

The SCSI device which the LSI53C895A is attempting to
select or reselect does not respond within the
programmed time-out period. See the description of the

SCSI Timer Zero (STIME0)

register, bits [3:0], for more

information 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. See the description of the

SCSI

Timer One (STIME1)

register, bits [3:0], for more

information on the general purpose timer.

7

5

4

3

2

1

0

R

SBMC

R

STO

GEN

HTH

x

x

x

0

x

0

0

0

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