Scsi Device Configuration Options - Adaptec 29320A-R Manual

Adaptec Ultra320 SCSI Cards User's Guide

SCSI Device Configuration Options

SCSI Device Configuration options can be set individually for each
connected SCSI device.
Note: To configure settings for a SCSI device, you must know
its SCSI ID (see
Sync Transfer Rate (MB/sec)—(Default: see following table) The
BIOS may negotiate for a transfer rate between controller and
device of up to 80 MB/sec for Wide transfers and 40 MB/sec for
Narrow transfers. The BIOS can use this setting to set the
starting point for negotiating the synchronous data transfer rate
to a slower speed. For example, in the case of Wide transfers, if
the Sync Transfer Rate is set to:
320, 160, or 80—The BIOS negotiates at 80 MB/sec.
40 or lower—The BIOS negotiates at the Sync Transfer Rate
setting.
Eventually, the BIOS completes negotiation. Later, the device
driver takes over. The device driver uses this setting as a
starting point for negotiating data transfers.
The following table describes the maximum synchronous
transfer rates. The default settings are designated by an
asterisk (*).
Negotiation Rate
Narrow mode
Wide mode
Note: If Initiate Wide Negotiation is set to No, the rates for
Wide devices are half those shown in the table.
Packetized—(Default:Yes) Packetized protocol is required to
operate at 320 MB/sec. When enabled, this option is available if
it is implemented in the device drivers. However, this option is
not supported by the BIOS.
3-6
Using SCSI Disk Utilities on page
Allowable Maximum Rates (MB/sec)
*40.0, 33.3, 20.0, 16.6, 10.0, 5.0, ASYN
*320, 160, 80.0, 66.6, 40.0, 33.3, 20.0, 10.0, ASYN
3-16).