 The magazine of the Melbourne PC User Group Beginners' Bytes: Part 1 Ron Wilby |
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Beginners' Bytes is a new feature this month, not to be confused with the Beginner's Tale (opposite). The idea is to return to the very basics of computer operation, last covered by the early episodes of "A Beginner's Tale" almost a year ago.
Starting Up
To get your computer into action, you must first "Boot" it, after turning on the power. Most of you will have your computer set up so that it "boots" after you switch on. You may not even know what is happening, just that various miscellaneous pieces of information are seen on the screen, accompanied by some beeping and scraping from the computer. You can't read what's on the screen because it "scrolls" off' the screen too quickly. The end result of all this will be a "menu" from which you can select the next action you want. This will usually be the selection of the program you want to run, then pressing the "Enter" key loads the program so you can start work. Loading means copying the program files from a disk into memory.
How It Really Works
Behind all this startup activity there is at work an "operating system." The operating system provides the interface between you and your computer. It executes the commands you enter from the keyboard and manages the system resources including the peripherals such as monitor, printer, mouse etc.
The System we (nearly) all use is called DOS. This stands for Disk Operating System, and it allows you to run other programs, called Application Programs, such as word processors, databases and spreadsheets. What are they? We'll go into that later.
Often, though, you are not in contact with DOS because it hides behind a secondary program that takes control of the computer soon after startup. This program is known as a "Shell" and commands are issued from a screen, called a menu, on which several alternatives are displayed for you to select.
Even if you have a shell, I strongly recommend you get behind it and learn a little about the basics of your operating system. To make best use of your computer you need to be an adequate DOS user (which doesn't mean an expert).
BIOS
When switched off' the computer is dead. There is nothing in memory. DOS is hanging about somewhere on hard or floppy disk but is powerless. Before the operating system can operate, we need something to start the whole thing, something to breathe life into this
dead computer. This something is called the BIOS (stands for Basic
Input Output System) and is built into the computer when you buy it. No BIOS, no go! When you switch on the power your BIOS is ready and waiting and performs POST
(Power On Self Test). This is the
beeping and scraping bit mentioned above. POST checks that your hardware is in working condition and you will see on screen messages from the in the first half-minute or so after power on.
Booting
After the POST routine (about half a minute) t BIOS hands over control to DOS. At this point need a "System Disk," either a floppy, which
must be in drive A, or your hard disk.
Capital letters like A, B, C etc are the names your disk drives. DOS recognises these letters drive names when they have a colon after the A:, C: etc. Your first floppy disk drive is alway your hard disk C:. If you have a second floppy it will be B: and more hard disks (or partitions)
are
possible.
DOS looks at drive A first. If there is a system there, then that disk is used for startup. When drive A contains disk without the System file; get an "error message" telling you it's a "non-system disk, replace and try again" or words effect. If there is no disk in drive A (or the do open) DOS moves on to drive C, your hard disk. Most PCs start from drive C, but be aware that
if there is a disk left in drive A, DOS will try to that first and your computer may fail to start.
When DOS has found a system disk it proceed "boot" your computer, which means that DOS at a file called CONFIG.SYS for information
about how you want your computer configured. DOS looks at a file called AUTOEXEC.BAT to find
which of the various DOS programs are to be "loaded" i memory after which the computer is ready
and willing to accept your commands. Later I'll show you how to modify CONFIG.SYS and AUTOEXEC but for now you should see on screen the DOE prompt, which will be A:\ or C:\ followed by blinking line. This line is DOS saying to you " your command here, Master." If, instead of
the DOS prompt, you have a menu on screen, there will be some command to take you from the menu
to the prompt. For DOS 5 type Alt + F4.
What we are going to do now is to examine s basics of computer operation. You'd be
surprised how many people perform miracles with wordprocessor or spreadsheet but have no
idea how to copy a file. At this stage you should have emergency "Start Up" disk, which is
basically a floppy disk formatted as a "System" disk. Never use your original DOS disks, use the DISKCOPY command to make copies and use them. To
make the startup disk you get the DOS prompt on as described above, put a new floppy disk in A and at the prompt type FORMAT A:/S.
Making a complete startup disk requires some file copy and I am about to tell you how to do that in month's episode.
Meanwhile, to get the DOS prompt, put your disk in drive A, press Ctrl, Alt and Del all to This will reboot your computer giving you the required DOS prompt on screen. Keep this
startup disk, you may need it in an emergency (see this month's episode of The Beginner's Tale).
I'll be back next month ....
Reprinted from the September 1993 issue of PC Update, the magazine of Melbourne PC User Group, Australia
