Notes

Outline

Booting PC’s and MS DOS

Booting the PC Switch On Power to Motherboard ROM Chips do POST I/O Set up System seeks MBR (Boot sector) PUTS data there in RAM System gets additional Operating System files as told by MBR

DOS BOOT MBR Found and as above secondary loader put in RAM Secondary Loader moves IO.SYS and MSDOS.SYS into memory from HD DOS checks for CONFIG.SYS IF FOUND system reconfigured as told DOS Loads COMMAND.COM Checks for AUTOEXEC.BAT in root IF Found command.com carries out commands included. IF Not Found Command.com displays date and time prompts.

Config.sys  Adds Drivers DEVICE=C:\WINDOWS\HIMEM.SYS DOS=HIGH, UMB DEVICE = EMM386.EXE NOEMS DEVICEHIGH=C:\DOS\SETVER.EXE STACKS=9,256 rem DEVICEHIGH = C:\DOS\ANSI.SYS FILES=99 DEVICE=C:\MTM\MTMCDAI.SYS /D:MTMIDE01 DEVICE=aspippa3.SYS rem means comment..above for zip drive

Autoexec.bat Carries out Commands C:\WINDOWS\COMMAND\MSCDEX.EXE /D:MTMIDE01 /M:10 /L:F ECHO OFF PROMPT $p$g PATH A:\;C:\WINDOWS;C:\;c:\DOS loadhigh C:\WINDOWS\mouse.COM /Y guest

Defaults and Logged drives DOS and other OS’s have defaults A default is what is chosen if there are many options. The default drive is the LOGGED drive If you have a A, C, D, drive typing DIR without a file spec gives a dir of the logged drive and path

Changing Drives Typing the letter of a drive and the colon symbol (:) and hitting the enter key changes that drive to the logged or default drive Typing A:   and hitting enter changes to the A drive The A:  should now show on the prompt line

Directories You also can be logged into a directory or subdirectory. The Prompt shows what directory you are in If the prompt shows C:\DOS you are in the DOS directory in the C drive

Changing Directories The CD command changes the directory you are in. CD \  Changes to the root directory CD \WINDOWS  Changes to windows if it is off the root directory NOTE:  \  in a command means starting at the root directory of the drive.

Common Errors Must be in the proper drive and directory for some commands CD COMMAND works if command is inside the present directly only CD \COMMAND works only if command comes off the root CD \WINDOWS\COMMAND always works if command is inside windows File Spec must be Exact!

Common DOS Commands DOS Syntax includes a Command, a space, a from specification, a space, and a to, or a where, a space, and optionally a / and a switch DIR A:\     Gives a directory of the specified drive and/or directory in this case the A drive DIR \WINDOWS gives a directory of the windows directory if it is on the logged drive Format A:\  Formats a Floppy A:\ is the what

Switches Format A:\ /S  Formats and puts operating system files on the floppy /S is a DOS Switch.  It adds the operating system to the disk A Switch Modifies a DOS Command CHKDSK C:  Checks and Repairs HD and tells condition, size and available room CHKDSK C: /F Chkdsk Switch to fix lost chains

CHKDSK Fix Disk Check Capacity & Room Check RAM Switches F to fix, etc.

DEL or ERASE The Del or ERASE command erases files DEL C:\MYFILE.SYS erases a file named MYFILE.SYS in the root dir of the C drive * is the wild card command *.* means all files DEL *.* erases all files in the logged folder. If you were in windows this would erase all unprotected files in this directory

ATTRIB COMMAND ATTRIB A: Shows hidden files and Attributes R, A, S, H ATTRIB A:MYFILE.ECE -R Changes attributes of files System: S (Used by the OS) Hidden: H (can’t see in directories) Read Only: R (cant be changed) Archive: A (not backed up)

RMDIR and DELTREE RD C:\DOCS   or RMDIR C:\DOCS Removes the indicated directory The directory must be empty of files first Easy way is to DEL C:\DOCS\*.* first DELTREE C:\DOCS Removes the directory and files Also removes any subdirectories! Dangerous if not used properly!

Win 9X Variants Many commands have been dropped or changed in recent windows No DELTREE command, but DEL *.* /S erases all files in the logged directory and all subdirectories!

REN or RENAME REN myfile.bak newfile.tem Can rename a file to a new name! REN C:\DOCS\LETTER.DOC LETTER2 SYNTAX REN old file spec space new file spec

TREE TREE C:\DOS TREE A:\ Shows structure of indicated path Syntax TREE space DISK and/or DIRECTORY  Not in Windows DOS’s…

PATH Sets the places where DOS looks for command files PATH=C:\;C:\DOS Each separate path is separated by a ; Usually put in autoexec.bat Without path must specify files  location E.G:  C:\DOS\FORMAT A:

Internal vs External Commands DIR, Memory Resident in Command.com FORMAT, external requires finding the program FORMAT.EXE to work

Places to Look for Commands DOS directory in DOS PC’s Windows directory \WINDOWS\COMMAND \WIN95