Working complete PC
Student Diskette, "New Boot A Ver 2.0+"
Student CD-ROM, "Room 6359"
The student will become familiar with how to:
create a bootable floppy diskette in DOS,
copy important DOS drivers to it,
copy important technician tools to it,
setup the diskette to load drivers as it boots up.
The student will learn how to work in DOS at the command line to prepare a bootable diskette that can be used to boot up a PC that is failing to boot up from its hard drive and include on it some essential tools and drivers including CD-ROM support which the DOS operating system does not natively support.
This exercise begins with a diskette that has been provided to the student which is not bootable and that has the hardware level CD-ROM device driver file on it. The PC should have a full and complete installation of MS-DOS version 6.22 on the C: drive as well. Since the ultimate goal is to build a bootable diskette with CD-ROM support for DOS, the diskette will have to be formatted with the "make bootable" switch. Since FORMAT is a destructive command, the CD-ROM hardware level device driver must first be copied off of the diskette to a safe location. Then the diskette can be formatted and then later the CD-ROM driver can be copied back onto it again. Boot up the PC to the hard drive (C: prompt) and then insert the diskette that has been provided. Copy the CD-ROM device driver to the DOS directory:
C:\>copy a:\oakcdrom.sys \dos 1 files(s) copied. C:\>_
Now format the diskette and make sure that it will be bootable by providing the correct switch:
C:\>format a: /s
Insert a new diskette in drive A:
and press Enter when ready...
Follow the prompts and press [Enter] when asked for the volume label (does not need a volume label) and press [N] then [Enter] when prompted to format another. This procedure created the bootable floppy because of the "/S" switch added to the end of the command. Now change into the DOS directory and copy the two essential DOS disk handling commands to the floppy:
C:\>cd dos C:\DOS>copy fdisk.exe a: 1 files(s) copied. C:\DOS>copy format.com a: 1 files(s) copied. C:\DOS>_
Now copy the extended memory manager to the floppy:
C:\DOS>copy himem.sys a: 1 files(s) copied. C:\DOS>_
Now copy the DOS disk caching utility to the floppy:
C:\DOS>copy smartdrv.exe a: 1 files(s) copied. C:\DOS>_
Now copy the utility that can test the surface integrity of a disk to the floppy:
C:\DOS>copy scandisk.exe a: 1 files(s) copied. C:\DOS>_
Now copy the tool that can restore a disks ability to boot up to the diskette:
C:\DOS>copy sys.com a: 1 files(s) copied. C:\DOS>_
Copy the DOS ATAPI driver to the diskette. The DOS ATAPI driver is a universal driver that communicates with the CD-ROM drive's hardware level device driver. The CD-ROM's hardware level device driver is developed by the CD-ROM drive's manufacturer. The driver communicates directly with the drive and translates unique device commands and operations into a published industry standard language called ATAPI. The operating system designers develop a driver that plugs into the operating system core translating low level operating system functions messages and operations into ATAPI as well. This way the OS can develop and change and the OS designers simply build a new version of their ATAPI support driver. The CD-ROM manufacturer can change the design of their devices independently as well and simply change their device driver but still translate back to ATAPI. Both sides can then evolve and change independently without having to share any internal secrets or wait for the other to get back to them with updates:
C:\DOS>copy mscdex.exe a: 1 files(s) copied. C:\DOS>_
Remember that at the very beginning of this exercise, the diskette that was provided had the hardware level CD-ROM device driver on it. This file was copied into the DOS directory before the diskette was formatted. FORMAT is a destructive command that removed all existing files on the diskette so that now the hardware level CD-ROM device driver must be copied back onto it:
C:\DOS>copy oakcdrom.sys a: 1 files(s) copied. C:\DOS>_
Now set up the diskette so that when it boots, all drivers on it will automatically be launched. This requires the creation of a CONFIG.SYS and an AUTOEXEC.BAT on the diskette. It also requires that you understand which of the files just copied to the diskette are drivers and which ones are not drivers. The drivers on the diskette are: HIMEM.SYS, OAKCDROM.SYS, SMARTDRV.EXE, and MSCDEX.EXE. First change to the root of the diskette and then create the CONFIG.SYS:
C:\DOS>a: A:\>copy con config.sys device=himem.sys /v /testmem:off device=oakcdrom.sys /d:cd01 _
These two lines will load the two *.SYS named drivers but DOS has another situation that can be controlled from a CONFIG.SYS command; it only reserves up to drive letter E: unless otherwise instructed to do so. Let's instruct it to reserve the drive letters up to letter Z: by adding this command:
A:\>copy con config.sys device=himem.sys /v /testmem:off device=oakcdrom.sys /d:cd01 lastdrive=z _
Now get out of the "copy con" operation that creates a new text file, by pressing and holding the [Ctrl] key and then typing the letter [Z], then release the [Ctrl] key and press [Enter]:
A:\>copy con config.sys device=himem.sys /v /testmem:off device=oakcdrom.sys /d:cd01 lastdrive=z ^Z 1 files(s) copied. A:\>_
Now create the AUTOEXEC.BAT to load SMARTDRV.EXE such that it will create an 8MB disk cache in RAM, then display a summary on screen. Also load MSCDEX.EXE such that it will establish access to the CD-ROM as drive letter Q. Both are executable (having EXE or COM file extensions) and so can be launched from the AUTOEXEC.BAT:
A:\>copy con autoexec.bat smartdrv 8192 8192 smartdrv mscdex /d:cd01 /L:Q ^Z 1 files(s) copied. A:\>_
At this point the system should be rebooted to the diskette to be sure that it does boot up the system and load all drivers withou any problems or error messages. If it does load the disk cache and display the summary on screen and MSCDEX indicates that driver "CD01" is drive letter Q then the diskette works.
Copyrightę2000-2006 Brian Robinson ALL RIGHTS RESERVED