By Bob O'Donnell
Though floppy drives and floppy disks are increasingly falling out of favor, there are many occasions when a single floppy disk can make the difference between being able to use your computer or not.
I’m referring specifically to a boot disk, which is a floppy disk that allows you to boot, or startup, your computer without having to access the hard drive. A boot disk contains all the necessary operating system files your computer needs to get started. Boot disks can be tremendously important for many different applications and, frankly, no computer user should be without one.
For example, if your hard drive fails, or if you have the misfortune of contracting a computer virus that attacks your hard disk’s master boot record (as many of them do), or if some of your important operating system files get accidentally deleted or otherwise corrupted, a boot floppy will be your savior. (For more advice on addressing on common boot problems, see the "PC Startup Troubleshooting Tips" article.)
In addition, if you ever want to reformat your hard disk or reinstall Windows 95 (or Win98, for that matter) from the CD, you’ll also need to have a boot disk. (For more on this issue, see "Starting Over: Repartitioning, Reformatting and Reinstalling.") Some older DOS games also work better if you boot your computer from a startup disk.
In recognition of this importance, Microsoft made the process of creating a basic Windows 95 boot disk very easy. All you have to do is open the Add/Remove Programs Control Panel. To do that, click on the Start button, go up to Settings, select Control Panel from the list of available choices and when the Control Panel window opens, just double click on Add/Remove Programs. Once that's open, click on the Startup Disk tab and click on Create Disk… You’ll be prompted to insert the Windows 95 CD into your CD-ROM drive (in most cases) and to put a floppy disk into the floppy drive. After a minute or two, you’ll have a disk that includes all the critical files necessary to start your computer and "see" your hard disk. The basic boot disk also includes important disk utilities such as Scandisk.exe, Fdisk.exe and Format.com.
Unfortunately, that disk will not be able to "see" your CD-ROM, which means you won’t be able re-install Windows 95 from a CD, run a CD-based DOS game or do any of a number of other possible applications. If you boot with this disk and try to switch to the CD you’ll get the heart-warming "Invalid Drive Specification" error message in DOS.
The "simple" answer to this problem is to just install your CD-ROM driver onto the disk—that's the answer most magazines and books will give you. The problem is, they don't tell you how to do that.
(By the way, Microsoft clearly saw the errors of its ways here because the regular Windows 98, Windows 98 Second Edition (SE) and Windows Millennium Edition (ME) boot floppies—which you create in the exact same way as you do under Windows 95—do include a CD-ROM driver. In fact, they include both a generic IDE/ATAPI driver as well as a generic SCSI CD-ROM driver. Even better, a boot floppy created under Windows 98 or Windows ME will boot a Windows 95 machine without any problems or conflicts at all. Now, why Microsoft couldn't have done this in the first place is beyond me....)
Before I get to the specifics of how it's done with Windows 95, let me give just a bit more background. In order for a CD-ROM drive or any other device (such as a sound card) to be "visible" in DOS, you have to tell the operating system that it's there. You do that through specific pieces of software called device drivers, or just drivers for short, that "communicate" between your operating system and these devices (such as the CD-ROM drive).
There are different types of driver files, but for a boot floppy you need a "real mode" or 16-bit driver for your CD-ROM drive. ("Real mode" refers to a type of memory allocation system used by DOS and early Intel processors.)
In order for DOS drivers to work on a boot floppy you need to both have copies of the appropriate drivers on the disk and put references to those driver files in some of the operating system startup files also found on the startup floppy. Without those references, the operating system doesn't know the drivers are there and won't be able to load them. And if it doesn't load them, well, we're back where we started—an "invisible" CD drive.
In the case of a CD-ROM, you need two driver files, one that's specific to your machine and one that's included with the standard Windows 95 installation. The file that's specific to your machine is the "real mode" or DOS driver I referred to earlier. The startup files you need to adjust are Config.sys, which is included on the standard boot floppy, and Autoexec.bat, which is not.
If you also wanted to add a sound card driver to this floppy in order to play games, you would copy over an additional file and then make additional changes to the existing Config.sys startup file.
For the purposes of this article, I’m only going to describe how to install the CD-ROM driver for an IDE/ATAPI CD-ROM drive, which is what most computers have. The same basic principles apply to SCSI CD-ROMs and sound cards, although you may need to make some additional alterations to the startup files to get them to work properly. Check the documentation that came with your sound card or with your PC for more details.
OK. Now it's time to describe how to create your CD-ROM driver-equipped boot disk. As I explained, the first thing to do is to find a copy of the real-mode driver for your CD-ROM. Note that this is different from the 32-bit Windows 95 driver that your CD-ROM uses while running under Windows 95. Most 32-bit drivers are called virtual device drivers and have the file extension .vxd, whereas many real-mode CD-ROM drivers end with a .sys at the end of their file name. For example, the real-mode CD-ROM driver for the Dell Computer I’m currently using, which has an NEC CD-ROM, is called nec_bm.sys.
On some computer systems you can find the real-mode driver on a separate floppy that came with the computer (or with the CD-ROM drive itself, if you added it separately), but in many cases, particularly with newer computers, you’ll find that you don’t have it. In that case, you should first check the computer manufacturer’s web site, then call them if you can’t find it there. If you know who made the CD-ROM drive mechanism used in your computer, then you can use the same techniques with that company.
If you don’t know who made the drive you can often find out by typing in the FCC ID, which has to be on a sticker somewhere on the drive, into a special FCC database (linked here) that tracks all that information. Every company that sells a computer product has to have a unique ID, so by typing that ID in, you can find out the name of the company that sold the drive, as well as an address and a phone number.
Once you’ve found out who made the drive, another possible source for drivers is one of the many driver sites here on the Web, such as The Driver Zone, WinDrivers.Com, WinFiles, or Frank Condron's World o' Windows.
After you copy the CD-ROM driver over to the startup floppy, you’ll also need to copy over a Microsoft-supplied system-level CD-ROM driver called MSCDEX.EXE. You should find a copy of it in your Windows/Command folder on your C: drive. If it's not there, you'll definitely find it on the Windows 95 CD that came with your computer.
The next step is to open the Config.sys file and add one line to it. To do that, you'll use the DOS Edit application that’s installed on the boot floppy as part of the standard Create System Disk routine.
To get to the application, open an MS-DOS window by going to the Start menu and selecting MS-DOS Prompt from the Programs menu item. After the window opens, switch to your A: drive by typing A: and then Enter.
Once you get an A:\> prompt, type in "edit" (without the quotation marks) and hit Enter and you’ll be presented with a basic text editing program. Open the Config.sys file on your A: drive.
By the way, make sure you’re not editing the Config.sys file on your C: drive or you could have big problems. You should be able to easily tell because the basic Config.sys on the standard boot floppy has only one line in it and it refers to Himem.sys.
Put your cursor underneath that line and type in:
Device=A:\<name of your driver> /D:MSCD001
Don’t actually type <name of your driver>—that needs to be replaced with the exact spelling of the driver file you previously copied onto the floppy disk. So again, in my case it was:
Device=A:\nec_bm.sys /D:MSCD001
Save the Config.sys file and close it.
The next step is to create a simple Autoexec.bat file on the floppy. While you’re still in the Edit application, go to the File Menu and select New... Then type in the following line:
MSCDEX.EXE /D:MSCD001
When you're done with that, go up to the File menu, select the Save As… command and save the file as Autoexec.bat (capitalization doesn’t matter) on the A: drive. Exit the Edit program and then close the MS-DOS window by clicking on the X in the upper right hand corner.
That’s it.
Now you need to try it out. To do that, insert the boot floppy (you did put a new label on it, didn’t you?) into the floppy drive and restart the machine.
After the normal BIOS messages you should see some startup messages about MSCDEX and a few other things. Once you get the A:\> prompt, try switching over to the CD-ROM drive to make sure the driver worked by typing in D: (or whatever letter your CD drive is assigned to) and hitting return (make sure you have a CD-ROM disc of some sort in the drive—it doesn’t matter what).
If you get the D:\> prompt, try typing a DIR (or directory) command to make sure you can see the contents of the drive. You should see a list of all the files and directories on the root level of the CD you have in the drive. If so, you’ve successfully created a bootable floppy disk with a CD-ROM driver for your system. Congratulations!
If not, well, double check your typing and try again. You’ll get it eventually…..
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