Reset; Reset Device - Adaptec AHA-1740A Technical Reference Manual

EISA-to-Fast SCSI Host Adapter
7
0
The SCSI ID specifies either the SCSI address of a particular target, or the SCSI ad-
dress of the host adapter. The host adapter's ID can be found in bits 3-0 of the SCSI
Definition register.
When the Attention register is written to, the host adapter is interrupted. When the
command is completed, the host adapter (if enabled) will interrupt the host by writ-
ing to the Enhanced Mode (Group 2) Interrupt Status register. If the immediate com-
mand completed with an error, the first byte of the Mailbox In registers will contain
the appropriate error code.
Supported Immediate Commands
Reset (80h)
Resume (90h)
The control block commands are described below in alphabetical order.

Reset

F E D
Fields that are empty are reserved and should be set to zero.
This command allows the host, via software control, to reset a particular target or
the host adapter.
This command will always interrupt the host upon completion. The host should wait
until the interrupt is posted in order to determine if the reset was completed success-
fully.

Reset Device

If the Attention register contains the ID of a SCSI target, then this command is in-
tended to reset the associated device to a known state with minimum impact to other
devices on the bus.
On receiving this command, the host adapter will clear its internal memory of all out-
standing control blocks for the associated target. It will also clear any queued inter-
rupts for the associated target. A queued interrupt occurs when a control block
6 5 4
0 0 1
C B A 9 8
Enhanced Mode Firmware Description
3 2
SCSI ID
7 6 5 4 3
1 0 0 0 0
A
1 0
2 1 0 Byte
Offset
0 0 0 00
D 02
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