beautypg.com

Scsi interrupt enable one (sien1), Scsi, Interrupt enable one (sien1) – LSI 53C810A User Manual

Page 124

background image

5-50

Operating Registers

Register: 0x41 (0xC1)

SCSI Interrupt Enable One (SIEN1)
Read/Write

This register contains the interrupt mask bits corresponding to the
interrupting conditions described in the

SCSI Interrupt Status One

(SIST1)

register. An interrupt is masked by clearing the appropriate mask

bit. For more information on interrupts, refer to

Chapter 2, “Functional

Description.”

R

Reserved

[7:3]

STO

Selection or Reselection Time-out

2

This bit controls whether an interrupt occurs when the
SCSI device which the LSI53C810A was attempting to
select or reselect did 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 controls whether an interrupt occurs when the
general purpose timer is expired. 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.

HTH

Handshake to Handshake timer Expired

0

This bit controls whether an interrupt occurs when the
handshake-to-handshake timer is expired. The time
measured is the SCSI Request-to-Request (target) or
Acknowledge-to-Acknowledge (initiator) period. See the
description of the

SCSI Timer Zero (STIME0)

register,

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

7

3

2

1

0

R

STO

GEN

HTH

x

x

x

x

x

0

0

0