Siemens SIMATIC Rack PC 840 Manual page 154

Controller
Extended BIOS Translation for DOS Drives > 1Gbyte
When this function is enabled, you can operate drives of up to 8 Gbyte capacity
(2 Gbytes per partition) under MS-DOS 5.0 or a later version. The SCSI BIOS
must be enabled for this purpose.
Formerly, only drives with a capacity of up to 1 Gbyte could be operated under
DOS 5.0.
Enabled
Disabled
Caution
Save the data on your hard disk before you change the default setting. After
switching on you must repartition and format the hard disk with the MS-DOS
programs FDISK and FORMAT.
Host Adapter BIOS
If the SCSI devices can only be operated using additionally loaded drivers, you can
disable the SCSI-BIOS. This saves 16 Kbytes of system memory and saves time
starting the system.
Caution
If the SCSI BIOS is disabled, you cannot boot up from the SCSI devices
connected to the SCSI bus.
If you disable the SCSI BIOS, you can still call SCSI Setup using the
keys when starting the system and make changes.
Enabled
Disabled
Notice
Remember that you must install special SCSI drivers for your SCSI devices if you
disable the SCSI BIOS.
8-10
Drives of up to 8 Gbytes can be operated under MS-DOS 5.0
(default setting).
Drives of up to 1 Gbyte can be operated under MS-DOS 5.0.
The SCSI BIOS is activated (default setting).
The SCSI-BIOS is deactivated.
+
Ctrl A
SIMATIC Rack PC 840 Manual
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