Adaptec AHA-2740W User Manual page 70

AHA-2740W/2742W/2744W User's Guide
then the value selected here will be the maximum rate that the host
adapter will accept.
In most cases, the maximum value of 10.0 MBytes/sec can be used.
If the drive is not a Fast SCSI drive and cannot support the fast data
transfer rates, it can negotiate for a slower rate (this is standard SCSI
protocol). However, if a drive cannot accept values greater than 5.0
MBytes/sec (the highest standard synchronous transfer rate), then
the Fast data transfer rates should not be used for the device. Older
SCSI-1 devices may not accept the Fast data transfer rates, which
may result in erratic behavior or a hang condition.
Initiate Wide Negotiation
This option determines whether or not the host adapter will attempt
16-bit data transfer instead of 8-bit data transfer. The default setting
is yes.
When set to yes, the host adapter BIOS attempts 16-bit data transfer.
When set to no, the BIOS transfers data at 8-bits unless the SCSI
device itself request Wide negotiation.
For 16-bit data transfer, the effective transfer rate is doubled. For
example, a transfer rate of 10 MBytes/sec becomes 20 MBytes/sec,
8 MBytes/sec becomes 16 MBytes/sec, etc.
Note: Some 8-bit SCSI devices may have trouble handling
Wide negotiation, which may result in erratic behavior or a
hang condition. For these devices, set Initiate Wide Negotia-
tion to no.
Include in BIOS Scan
This option determines whether or not the host adapter BIOS sup-
ports devices attached to the SCSI bus without the need for device
driver software.
When set to yes, the host adapter BIOS controls the SCSI device.
When set to no, the host adapter BIOS will not search the SCSI ID for
devices to control; device driver software is needed to control the
SCSI device. The default setting is yes.
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Current Date: 8/3/94
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