Siemens SIMATIC RI 45 PIII Series Manual page 117

Maximum Sync
Fast SCSI devices (Ultra Wide) including the SCSI controller, support a data
Transfer Rate
transfer rate on the SCSI bus of up to 40 Mbytes/s with synchronous data
transfer. If you select Enabled in the Support for Ultra SCSI Speed menu
option, a transfer rate of 40 Mbytes/s is set automatically.
Enable
This function allows SCSI devices to release the SCSI bus while a command
Disconnection is being carried out. A typical example for use of this function is a tape drive
that does not need to access the SCSI bus while being rewound and can be
disconnected from the SCSI bus during this process.
You can disable the function if you have only one SCSI device connected. In
this case, disabling will improve performance.
Yes
No
Send Start Unit If this function is enabled, SCSI devices supporting this function will not be
Command
started until you receive the Start Unit Command from the SCSI BIOS. In
this way the SCSI devices can be switched on one after the other. This
function is used if the power supply to your system is not sufficient to start a
number of drives at the same time or in order to avoid peak turn-on currents.
You may have to change the settings on your SCSI devices so that this
function is supported (read your SCSI device documentation).
Yes
No
Multiple LUN You use this setting to decide whether an SCSI device with multiple LUNs
Support
(Logical Unit Numbers) can or cannot be used as a start drive.
Enabled
Disabled
Include BIOS Scan If this function is enabled, the SCSI device can be used as a boot drive. The
SCSI device is contacted by the SCSI BIOS and receives a drive name. A
message is displayed on the screen.
Yes
No
Note
In the case of drives which you know will never be used as a boot drive (DAT
drive, for example), you should set this function to No. This saves time when
starting the system.
RI 45 PIII, Manual
C79000-G7076-C817-01
The function is enabled (default setting).
The function is disabled.
The function is enabled.
The function is disabled.
The SCSI device is used as start drive.
The SCSI device is not used as start drive (default setting).
The SCSI device can be a boot drive and is given a drive
name (default setting).
The SCSI device is not contacted by the SCSI BIOS.
SCSI Option
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