THE KEYBOARD by malj

VIEWS: 361 PAGES: 2

									H403: PC Peripheral Devices: Practical Activities                             18ff62c2-6ae5-4762-bdd0-
e536770c6af7.DOC 01/03/10 6:12 AM IB


                                       THE KEYBOARD

There’s more to a keyboard than meets the eye. In a PC keyboard there’s a microprocessor inside: the keyboard
is actually a special purpose computer.

A basic keyboard driver is built into a PC’s operating system. All you have to do is plug it in, and it works.

However, there are some aspects of the keyboard’s operation that you can change, and that’s what this practical
activity is about. When you’ve finished you should be able to:

             change the typematic rate and delay
             use foreign language and graphics characters in a document


1        TYPEMATIC RATE AND DELAY
Exit to DOS

The keyboard has auto-repeat - that is, if you hold down a key, it will repeat. This is handy for drawing lines in a
document: ================= Try it. Hold down the equals = key, and watch what happens.

DOS calls auto-repeat TYPEMATIC, and you can change the repeat rate (speed), and the delay - that is, how
long you must hold down a key before it starts repeating.

To change them, you use the MODE command:

MODE CON: RATE=1 DELAY=4

Do this, then test the auto repeat.

Now, find out the fastest auto-repeat rate, and the range of the DELAY parameter.

Fastest auto-repeat ______________________. Delay shortest: ________ Delay longest ________

Some explanations:

MODE is a DOS utility which controls peripherals.
CON: is DOS’s name for the keyboard/screen combination; it means CONSOLE, an old-fashioned name for
terminal. DOS treats all peripherals as though they were disk drives - hence the colon (:) after CON. (You may
already have used the COPY command with CON:. The fact that the copy command works with CON: proves
that DOS is treating it like a disk drive.)
RATE and DELAY mean what they say. However, you must always use both in the MODE CON: command.

For more information on Mode, try MODE /?

By the way: you can also change the default rate in most modern CMOS setup programs. We can’t do that here,
as CMOS settings are password protected, but you could try it at home if you have a PC. You might also be able
to change the NUMLOCK default, so that the PC starts up with NUMLOCK off.


2        FOREIGN LANGUAGE AND GRAPHICS CHARACTERS
You can display these by holding down the ALT key while you type a number in the numeric keypad (you must
use the numeric keypad, not the row of numbers above the alphabet keys).



                                                         1
H403: PC Peripheral Devices: Practical Activities                            18ff62c2-6ae5-4762-bdd0-
e536770c6af7.DOC 01/03/10 6:12 AM IB

From the DOS prompt, try ALT 132

What did you get? ____________                               Teacher’s signature: _______________________

Try ALT 65 What did you get? _____________                    Teacher’s signature: _______________________

By the way: DOS has a way of changing the keyboard layout to match different languages. For example, the Z
key on a German keyboard is in a different position. Unfortunately, the key labels don’t move, so this facility is
only of use to (German) touch typists wanting to use an American/English/Australian keyboard. We won’t be
doing it here. (The information is in your DOS manual, if you’re interested. Look up COUNTRY in the index.)

For most of us, ALT Keypad is the best way of getting foreign language characters. You can use this method in
any DOS or Windows program. (But read the note at the end of this prac.)

Now, from the DOS prompt, try some box-drawing graphics characters. Refer to the table nearby in this
document. The table is a PC Extended ASCII table.

Use EDIT to create a small double sided box with some foreign language characters inside, save it as
BOXxx.TXT (where xx are your initials) and TYPE the file to the screen. Show it to your teacher.

                                BOXxx.TXT: teacher’s signature: _____________________________________

Be creative: use EDIT to create a graphics character design, save it as ALTxx.TXT, type it to the screen, and
show it to your teacher.

                                ALTxx.TXT: teacher’s signature: _____________________________________

By now, you will have learned to use a wordprocessor. Start the wordprocessor, and use some foreign language
characters in a short document. Save it as WPROCxx.yyy (yyy is the wordprocessor’s default extension.)

      FOREIGN CHARACTERS IN WORDPROCESSOR: teacher’s signature: _________________________


Optional

If you know about batch files, you can display nice looking screens inside batch files. Simply create the file
using EDIT, then TYPE it inside a batch file. You can combine boxes and text to make an information screen,
for example. If you know about batch files, try this, and show the results to your teacher.

                        Optional: TEXT FILE IN BATCHFILE: teacher’s signature: ______________________

NOTE

In some Windows programs you must begin each number with a keypad 0 - for example, ALT 0132 instead of
ALT 132. So if ALT 132 doesn’t work, try ALT 0132, and see if you get a character. Unfortunately, it will
probably be the wrong one. This is because ALT 0xxx numbers don’t use the extended ASCII character system,
but instead use the ANSI character set. You will need to look up an ANSI character table to see what the 0xxx
numbers represent. Many wordprocessors will accept either system, giving you a choice.

Why give you a choice? The PC extended ASCII charcter set was developed by IBM especially for the PC; other
computers, such as MACs or Acorns don’t use it. The ANSI character set is an international standard, so if you
use ANSI foreign language characters, you can transfer files from a PC to a MAC (for example) without any
problems. Also, most modern printers use the ANSI character set. Not all printers will print the IBM characters
correctly - especially the box drawing characters.

End of keyboard prac.




                                                         2

								
To top