An operating system expects the computer to have at least two physical disk drives. MS-DOS recognizes drives A and B for two floppy disk drives, or A and C for a floppy and a hard disk drive. Some operations, such as copying files from one disk to another, require two drives. With MS-DOS, if you have only one physical disk drive, the operating system lets you treat it logically as two drives.

For example, if you give a command to copy from drive A to drive B, MS-DOS copies from the first diskette you place in the drive (A) to the computer’s memory. Then it prompts you to insert the disk for drive B. It copies from memory to the B disk you place in the drive. When the copy is complete, the screen prompts you to reinsert the original diskette in drive A.

You may be swapping diskettes this way quite often, and it is easy to forget which disk is which. To avoid accidentally losing your data, here is a tip for keeping the disks straight: always hold the disk for drive A in your left hand and the disk for drive B in your right. Another way to avoid writing on the wrong disk is to write-protect your source disk. This allows you to read information, but not write over it.

For more information on using a single floppy disk drive with MS-DOS, see your MS-DOS manual.

Using a hard disk drive

The Epson hard disk for Equity I+ has a capacity of 20 megabytes- about 20 million characters. This is equivalent to around 60 floppy disks. Using the hard disk greatly reduces the number of floppy disks you need and eliminates much of the disk-swapping you have to do. You can do almost all your work on the hard disk and copy your files to diskette as needed (to make backups, for example).

Although it has a lot of storage space, you should keep only the files you use regularly on the hard disk, to make sure you always have plenty of space available. Store your other files on diskette (you can use the ARCHIVE utility or BACKUP command in MS-DOS to back up your hard disk files). It is very important to back up all your hard disk files on floppy disks. The hard disk is very reliable, but you should always have backup copies in case you lose any of your data from the hard disk.

You need to prepare your hard disk before you can use it. If you are using a hard disk other than Epson’s, follow the preparation instructions provided with your hard disk.

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