Pentium MMX, K6 Full-size CPU Card with LCD, Ethernet, SCSI & High Drive Owner's Manual

74 SBC-596/599 User's Manual
When set to Yes, the host adapter attempts 16-bit transfer.
When set to No, 8-bit data transfer is used unless the SCSI
device itself requests Wide negotiation. The effective
transfer rate is doubled when 16-bit data transfer is sued
because the data path for Wide SCSI is twice the size of
normal 8-bit SCSI. For example, a transfer rate of 10
Mbytes/sec becomes 20Mbytes/sec, and a transfer rate of 20
Mbytes/sec (Ultra SCSI) becomes 40 Mbytes/sec.
n Maximum Sync Transfer Rate – This option sets the
maximum synchronous data transfer rate that the host
adapter supports. The default setting is 20.0 for the Ultra
Wide SCSI. The host adapter supports rate up to the Ultra
SCSI maximum of 20.0 Mbytes/sec (Ultra Wide SCSI
provides an effective maximum synchronous transfer rate of
40.0 Mbytes/sec). If your device is an Ultra SCSI device,
you can use the maximum value of 20.0. If your device is
not an Ultra SCSI device select a transfer rate of 10.0.
If the host adapter is set not to negotiate for synchronous
data transfer (that is, Initiate Sync Negotiation is set to no),
then the maximum synchronous transfer rate is the maxi-
mum rate that the host adapter accepts from the device
during negotiation. (This is standard SCSI protocol.).
n Enable Disconnection – This option determines whether the
host adapter allows the SCSI device to disconnect from the
SCSI bus (sometimes called Disconnect/Reconnect).
Enabling disconnection allows the host adapter to perform
other operations on the SCSI bus while the SCSI device is
temporarily disconnected. The default setting is Yes.
You should leave Enable Disconnection set to yes if two or
more SCSI devices are connected to the host adapter. This
optimizes SCSI bus performance. If only one SCSI device
is connected to the host adapter, set Enable Disconnection
to No to achieve slightly better performance.
n Send Start Unit Command – This option determines whether
the Start Unit Command is sent to the SCSI devices at boot
up (most devices do not require this). The default setting is
No.