MS DOS Command: DRIVER.SYS

Reference from Microsoft MS-DOS cmd help

Description

Creates a logical drive that you can use to refer to a physical floppy disk drive. This device driver must be loaded by a DEVICE or DEVICEHIGH command in your CONFIG.SYS file.

A logical drive is a pointer to a physical disk drive in your system. The logical drive is associated with a drive letter (for example, A or B). You can specify parameters to describe the disk drive to MS-DOS.

Syntax

DEVICE=[drive:][path]DRIVER.SYS /D:number [/C] [/F:factor] [/H:heads] [/S:sectors] [/T:tracks]

Parameters

[drive:][path]

Specifies the location of the DRIVER.SYS file.

Switches

/D:number	Specifies the number of the physical floppy disk drive. Valid values for number are in the range 0 through 127. The first physical floppy disk drive (drive A) is drive 0; a second physical floppy disk drive is drive 1; a third physical floppy disk drive, which must be external, is drive 2. For a computer with one floppy disk drive, drives A and B are both numbered 0; for a computer with multiple floppy disk drives, drive B is numbered 1.
/C	Specifies that the physical disk drive can detect whether the drive door is closed (change-line support).
/F:factor	Specifies the type of disk drive. Valid values for factor are as follows: 0 160K/180K or 320K/360K 1 1.2 megabyte (MB) 2 720K (3.5-inch disk) or other 7 1.44 MB (3.5-inch disk) 9 2.88 MB (3.5-inch disk) The default value for factor is 2. Generally, if you use the /F switch, you can omit the /H, /S, and /T switches. Check the default values for these switches to make sure they are correct for the type of disk drive you are using. To determine the appropriate values for the disk drive, see the disk-drive manufacturer's documentation. If you specify the /H, /S, and /T switches, you can omit the /F switch.
/H:heads	Specifies the number of heads in the disk drive. Valid values for heads are in the range 1 through 99. The default value is 2. To determine the correct value for your disk drive, see the disk-drive manufacturer's documentation.
/S:sectors	Specifies the number of sectors per track. Valid values for sectors are in the range 1 through 99. The default value depends on the value of /F:factor, as follows: /F:0 /S:9 /F:1 /S:15 /F:2 /S:9 /F:7 /S:18 /F:9 /S:36 To determine the correct value for your disk drive, see the disk-drive manufacturer's documentation.
/T:tracks	Specifies the number of tracks per side on the block device. Valid values for tracks are in the range 1 through 999. The default value is 80, unless /F:factor is 0, in which case the default value is 40. To determine the correct value for your disk drive, see the disk-drive manufacturer's documentation.

Remarks

Disk-drive change-line support

The term "change-line support" means that a physical disk drive can detect when the drive door is opened and closed. Change-line support allows faster MS-DOS operation with floppy disks. The /C switch indicates to MS-DOS that the physical disk drive can support change-line error detection. To determine whether your disk drive has change-line support, see the disk-drive manufacturer's documentation.

Modifying or redefining a supported physical disk drive

For information about modifying the parameters of a physical disk drive that is supported by your hardware, see the DRIVPARM command. You can also use DRIVER.SYS to redefine a physical floppy disk drive.

Limitations on DRIVER.SYS

You cannot use DRIVER.SYS with hard disk drives. For information about substituting a logical drive letter for a hard disk drive, see the SUBST command.

Creating a duplicate logical drive

Suppose you want to use one physical floppy disk drive to copy files from one floppy disk to another. Because you cannot copy from and to the same logical drive by using the COPY or XCOPY command, you must assign a second drive letter to that physical drive.

If your system has just one physical floppy disk drive, you do not need to install DRIVER.SYS for this purpose. MS-DOS already assigns both logical drive A and logical drive B to that drive. Just copy files from drive A to drive B and switch disks when MS-DOS prompts you.

If your system has more than one floppy disk drive, then you need to use DRIVER.SYS to assign a second drive letter to the physical floppy disk drive.

Creating a new logical drive with different parameters

If you use DRIVER.SYS to assign a logical drive that has parameters different from those of the previously assigned logical drive, then the parameters of the previous logical drive will be invalid. Therefore, you should no longer use the drive letter corresponding to the previous logical drive.

Examples

To add an external 720K drive to your system, add the following line to your CONFIG.SYS file:

device=driver.sys /d:2

Since no location is specified, MS-DOS searches for DRIVER.SYS in the root directory of your startup drive.

Suppose you want to use a single 1.44-megabyte external disk drive to copy files from one floppy disk to another. To do this, you must add two identical DEVICE commands for DRIVER.SYS in your CONFIG.SYS file. This procedure assigns two logical drive letters to the same physical drive. You can then swap disks in the same drive during the copying process. The following example shows how to do this:

device=driver.sys /d:2 /f:7

device=driver.sys /d:2 /f:7