Optimizing MS-DOS: CONFIG.SYS File Configuration

Understanding MS-DOS CONFIG.SYS Configuration

The CONFIG.SYS file is crucial for configuring various system components, including MS-DOS, hardware, and applications, ensuring they function as intended.

System configuration information is primarily stored in the CONFIG.SYS file.

What is CONFIG.SYS?

It is a text file that contains special commands that configure computer components such as hardware (memory, keyboard, mouse, printer) for use by MS-DOS and applications.

It is the first file that runs when you start MS-DOS.

Location of CONFIG.SYS

It is usually located in the root directory, C:\.

CONFIG.SYS Runtime

MS-DOS executes this file each time you start your computer. However, if needed, you can instruct the system to skip it.

Why Modify CONFIG.SYS?

You can modify the system configuration to:

• Customize how MS-DOS utilizes hardware, memory, and files.
• Add new hardware or reconfigure existing components.
• Specify commands for MS-DOS to execute upon PC startup.
• Define multiple system configurations. For example, different users on the same computer can have distinct configurations.

This represents an advanced use of CONFIG.SYS commands.

Editing CONFIG.SYS

CONFIG.SYS can be edited to add or modify commands that configure the system.

To edit the file, you must use a text editor that saves files as plain text (ASCII), such as Notepad.

MS-DOS reads the CONFIG.SYS file only when the computer starts. Therefore, after making changes, the computer must be restarted for them to take effect.

CONFIG.SYS Syntax

Hardware Device Settings

Each hardware device (mouse, monitor, printer, keyboard, disk drives, and memory cards) has unique characteristics that can be customized.

MS-DOS uses a special program called a device driver to control each device.

For instance, MS-DOS uses a built-in device driver to monitor how information is read to or from a floppy drive.

MS-DOS includes built-in device drivers for the keyboard, monitor, hard drives, floppy drives, and communication ports.

While these built-in device drivers generally require no special action to use, you can customize certain characteristics of them using commands within CONFIG.SYS.

Other devices, such as memory cards and mice, come with their own device drivers. These are called installable device drivers because you install them by adding a command to your CONFIG.SYS file. Several installable device drivers are included with MS-DOS.

To use an installable device driver, add a DEVICE command for each controller to CONFIG.SYS.

When MS-DOS starts, it loads the device driver into memory. For example, to load the MOUSE.SYS device driver located in C:\MOUSE, you would add a command like the following to CONFIG.SYS:

When MS-DOS reads this command, the MOUSE.SYS driver loads into memory, where it remains and provides access to the mouse.

Generally, hardware device drivers are included in installation programs that automatically add the necessary commands to CONFIG.SYS.