oem.hlp (Table of Contents; Topic list)
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RAMDRIVE.SYS
Notes  Examples
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                                RAMDRIVE.SYS
 
Uses part of your computer's random-access memory (RAM) to simulate a hard
disk drive. This device driver must be loaded by a <DEVICE> or <DEVICEHIGH>
command in your CONFIG.SYS file.
 
RAM drives are much faster than hard disk drives because your computer can
read information faster from memory than from a hard disk. A RAM drive
appears to be a normal hard disk drive; you can use it just as you would any
hard disk drive. The most important difference between a real disk drive and
a RAM drive is that because it exists only in memory, information on a RAM
drive is lost when you turn off or restart your computer. You can set up as
many RAM drives as you want, up to the amount of memory your computer has.
To do this, add one RAMDRIVE.SYS line to your CONFIG.SYS file for each
additional RAM drive you want.
 
Syntax
 
    DEVICE=[drive:][path]RAMDRIVE.SYS [DiskSize SectorSize [NumEntries]]]
    [/E | /A]
 
Parameters
 
[drive:][path]
    Specifies the location of the RAMDRIVE.SYS file.
 
DiskSize
    Specifies how many kilobytes of memory you want to use for the RAM
    drive. For example, to create a 640K RAM drive, specify 640. If you
    don't specify an amount, RAMDrive will create a 64K RAM drive. You can
    specify a value from 4 to 32767. However, you cannot specify more memory
    than your system has available.
 
SectorSize
    Specifies the disk sector size in bytes. The size can be 128, 256, or
    512 bytes. (If you include a SectorSize value, you must also include a
    value for DiskSize.)
 
    Generally, you should use the default sector size of 512 bytes.
 
NumEntries
    Limits the number of files and directories you can create in the RAM
    drive's root directory. The limit can be from 2 to 1024 entries; the
    limit you specify is rounded up to the nearest sector size boundary. If
    you do not specify a limit, you can create up to 64 entries in the RAM
    drive's root directory. (If you include a value for NumEntries, you must
    also include values for DiskSize and SectorSize.)
 
    If there is not enough memory to create the RAM drive as specified,
    RAMDrive will try to create it with a limit of 16 directory entries.
    This may result in a RAM drive with a different limit from the one you
    specified.
 
Switches
 
/E
    Creates the RAM drive in extended memory.
 
    For RAMDrive to use extended memory, your system must be configured so
    that it provides extended memory, and a DEVICE command for the
    extended-memory manager (such as HIMEM.SYS) must appear in your
    CONFIG.SYS file before the DEVICE command for RAMDRIVE.SYS. In general,
    it is best to create a RAM drive in extended memory if your system has
    extended memory.
 
/A
    Creates the RAM drive in expanded memory.
 
    For RAMDrive to use expanded memory, your system must be configured so
    that it provides expanded memory, and the DEVICE command for the
    expanded-memory manager (such as EMM386, 386MAX, CEMM, or QEMM) must
    appear in your CONFIG.SYS file before DEVICE command for RAMDRIVE.SYS.
 
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