Write a program to set a password in cmos

By wajhi ·
I need to know if there is a possibility to write a program which can set a password in CMOS

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by cmiller5400 In reply to Write a program to set a ...

On the manufacturer of the BIOS. You may have better luck asking them directly. It may need to be scrambled in a certain way etc.

But in theory, you should be able to write some assembly code to do this...

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CMOS Settings And Configuartion Files

For many new users, CMOS setup, Config.sys, and Autoexec.bat are intimidating words. But they don't have to be. Basically, all these things do is provide your system with the information it needs to operate.
CMOS, which stands for Complementary Metal-Oxide Semiconductor and is pronounced "See Moss," is nothing more than a small computer chip that stores information about your system's configuration and is powered by a battery. The information stored in CMOS includes things like the current time and date, and the number and type of hard disk and floppy diskette drives that your system contains. CMOS setup is a program that lets you modify and save this important information.

While the CMOS setup provides your system with a lot of information, your computer probably has two other files that contain important system information. The Autoexec.bat and Config.sys files are consulted by your operating system every time you start your computer.


The Autoexec.bat file is a special batch file that contains a number of disk operating system (DOS) commands that are automatically carried out in sequence. A few common commands found in this file are: the PATH command that tells DOS where to look for files and commands; the MODE command that has to do with using peripherals (like a mouse or a printer); the SET command that simply tells where programs can access information; and commands that do not remain in memory once your system is turned off (like a command that lets you go directly into an application upon starting the system). For example, the command @ECHO OFF tells DOS not to display each command as it is processed. And PROMPT $P$G allows you to see what directory you are in while using the system.

While the Autoexec.bat file is not a must for all systems, if you have a hard drive with several programs loaded, it would be advantageous to have the file. Otherwise, you'll have to type certain commands every time you start the system.

Below is an example of an Autoexec.bat file that instructs a computer to go directly into Microsoft Corp.'s Microsoft Windows. (The C:\WIN line tells the computer to start Windows.)



The Config.sys file is a text file that has configuration commands for DOS when the system is started. Three different configuration commands are found in this file: DEVICE=, for using a peripheral device (such as a scanner or mouse); BUFFERS=, which lets DOS know the number of areas to set aside to store temporary data; and FILES=, which sets the number of files that can be opened at the same time. If no Config.sys file is present on your system, then DOS uses default settings.

Below is an example of a Config.sys file that loads several devices including a mouse and a memory manager.


NOTE: Some of the commands in the above Autoexec.bat and Config.sys files may seem pretty complex. However, you shouldn't worry too much about them, since most software applications make the necessary changes to these files for you upon installation. There are also certain software applications to help you set up your system configuration. These will be discussed later.

The Importance Of CMOS Setup, Autoexec.bat, And Config.sys

The CMOS setup and the Autoexec.bat and Config.sys files are important for several reasons.

First, your system can't operate properly without the correct CMOS settings.

Second, the right Autoexec.bat and Config.sys file command statements can make your system operate more effectively. For example, if you include a memory manager in your Config.sys, then your system will be able to use its memory to its fullest potential.

Third, without the right Autoexec.bat and Config.sys files, your system may not work properly or may not work at all.

Therefore, the CMOS setup and configuration files are vital to your system's operation. In fact, since these settings and files are so important, it is critical that you save the CMOS setting information by either writing it down or using a program that will save this information to a file for you as well as keep a hard copy or back-up of your Autoexec.bat and Config.sys files. You should also have a bootable diskette (a diskette that has the operating system files needed to start your system) in case your computer ever has problems when you start it.

Changing CMOS Settings And Configuration Files

There are several situations when you will want to access your CMOS setup program. These include:

* You have to reconfigure your CMOS setup because of a computer virus, a system crash, a dead CMOS chip battery . . . or some other reason.

* You have upgraded your system (you added a hard disk or more memory, for example) and must change the CMOS settings accordingly.

Accessing the CMOS isn't too hard. The following message (or one similar to it) will appear at the very beginning of the boot process:

Press F1 key to enter SETUP program

To access the setup program, simply press the F1 key (or whatever key is indicated). A list of options appear on the screen. These options will be similar to: Standard CMOS Setup, Advanced CMOS Setup, Advanced Chipset Setup, Change Password, Options for writing and not writing to CMOS, etc. You are concerned mostly with the Standard CMOS Setup. Here your options include those for changing or reconfiguring the time, date, hard disk, floppy drive, display, and keyboard.

The first time you venture into the CMOS Setup you may just want to look over the various options and make no changes. Even if you do change an option or two accidentally, you can always exit the CMOS Setup Program without saving the changes (select Do Not Write To CMOS and Exit). There are also software programs available to help you make changes to and view your system's CMOS Setup. These will be discussed shortly.

You can make changes to the Autoexec.bat and Config.sys files with any ASCII text editor (like DOS commands EDLIN or EDIT) or word processor. And most likely there will come a time when you will want to make a change. For instance, someday you may install a program that changes one of these files and causes a conflict.

CMOS Software

There are basically two groups of commercial and shareware programs that help you control your CMOS: those that display current CMOS settings and those that aid in setting up or changing CMOS settings and/or configuration files. Both types can be quite useful.

Displaying and printing out information on CMOS settings is very important, especially in the case of computer disasters, such as viruses that can erase this vital information. TouchStone Software's CheckIt provides such information on CMOS settings. All pertinent settings are displayed on your screen: current date, time, floppy drive present, existing memory, display type, and type of hard drive(s) present. It also lets you save this information to an activity log for future reference.

There are also many shareware programs that display and save your system's CMOS. (Shareware programs are programs that users can try for free. If a user likes a program, he or she is usually asked to pay a small service or registration fee. You can download, or transfer, shareware from most bulletin boards and online services or purchase it from shareware distributors). These CMOS utility programs include: CMOSGET.COM/CMOSPUT.COM, which saves and restores CMOS settings; CMOS.EXE, which displays CMOS information; CMOSALAR.EXE, which checks the CMOS battery; ICMOS.EXE, which displays CMOS information; CMOSSAVE.EXE/CMOSREST.EXE, which saves and restores CMOS settings; CMOSCHK.EXE, which checks CMOS settings against an information file; and CMOS_RAM.EXE, which saves and restores CMOS settings. (There are many other programs out there.)

Some other programs will help you change or set up your configuration files or CMOS settings. One very basic shareware program called Setup lets you easily change some of your CMOS settings.

There are also commercial and shareware utilities that simplify loading multiple Config.sys and Autoexec.bat files. BootCon is one such menu-driven commercial utility program that manages configuration options for you.

You may or may not need such programs right now. However, as software programs become more complex, there will probably come a day when a utility like BootCon will be of use to you. For example, you can select the device drivers your computer loads with BootCon. (A device driver is a program that tells the computer how to communicate with a device, like a scanner or a mouse.) This is useful because there's no reason to load drivers when you know that you won't be using them for a project. BootCon lets you choose the appropriate set of configuration files so you load only the drivers that you know you will be using.

BootCon, being menu-driven, is also relatively easy to use once you get used to working with configuration files. You use your favorite ASCII text word processor to edit your configuration files. Upon running the setup program and selecting your sets of configuration files, you simply reboot. The Bootcon menu appears with configuration set options. You simply select the one you want.

As you can see, CMOS, Autoexec.bat, and Config.sys are strange words. But you can control them. And with a little knowledge, there's no need to be fearful.
More info here:**9.asp

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