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Device Drivers


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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