Accusys ACS-8990 User Manual page 56

2.1.3 Wide
Enable or Disable (Default: Enable).
SCSI Interface
SCSI-2
Wide SCSI
Ultra SCSI
Ultra Wide SCSI
Ultra 2 SCSI
Ultra 160 SCSI
Ultra 320 SCSI
2.1.4 Lun Map
Select a Logical Unit Number (LUN 0 to LUN 7) or enter the desired LUN (LUN #,
up to LUN 127) and a corresponding slice on which to map it.
2.1.5 QAS
Enable or Disable (Default: Enable).
Quick Arbitration and Selection provides increased overall system performance by
allowing arbitration to occur without incurring the overhead of intervening BUS
FREE phases, saving up to microseconds per operation. This is significant when
compared to the 1.6 microseconds it takes to transfer each 512-byte sector of data
at 320MB/sec. Rather than waiting for a BUS FREE phase, a target may initiate
arbitration by issuing a QAS REQUEST message. The devices on the bus may
"SNOOP" the message and participate in the arbitration. QAS can only be enabled
if information unit transfers are enabled.
Because of ACS7485 (LSI53C1030T SCSI chip) had some compatible issue with
other HBA vendor, so F/W had created a QAS menu item to avoid this issues.
HBA Vendor
------------------------------------------------
Adaptec
LSI
ATTO
Please follow above table to match your test environment.
54
ACS-8990/89200/89230 User's Manual
Wide Fast
Disable [ENT]
Enable [ENT]
Disable
Enable
Enable
Enable
Enable
A RAID may be divided into several logical units (that portion of a disk array
seen by the host system as a single logical device). ACS-8990 can support up
to 16 logical units in total.
QAS setting
Enable (Default)
Disable
Don't care
Ultra Ultra2 Ultra 3
[ENT]
[ENT]
[ENT]
[ENT]
Ultra 320
[ENT]