Epson 386SX - Manual (Page 126)

Formatting a diskette to 720KE3
If you want to format a diskette to a capacity of 720KB in your
1.44MB diskette drive, you need to use a switch with the
FORMAT command.
The /F:size switch tells the FORMAT command to format the
diskette as the size specified in the command even if the
capacity of the diskette drive is different. You can format a
1.44MB or a 720KB diskette to a capacity of 720KB using this
switch.
For example, to format a 720KB diskette in your 1.44MB
diskette drive, enter the following command:
FORMAT A: /F:720
Use this command when you follow the instructions in this
section to format a diskette.
Backing Up Data
It is very important to keep backup diskettes containing copies
of the files you create. You can copy your data (text and
program files) in several ways:
You can use the COPY or XCOPY command to copy
individual files or groups of files.
You can use the DISKCOPY command to make an exact
duplicate of a diskette.
4-30 Using MS-DOS with Your Equity 386SX