The Online World resources handbook

Using online services http://home.eunet.no/~presno/bok/3.html
displayed on your screen.
The characters you see on your computer's screen are based on a code. The
computer finds the characters to display from a table built into your system's hardware
or software.
Most personal computers can be preset to use various tables depending on your
needs. When communicating in English, you may want it to show Latin characters.
When writing in Japanese, you may want it to display Kanji characters.
Those writing in Norwegian, often want to use the special Scandinavian characters
¯ÿÊ Â . If the first two of these Nordic characters read like the symbols for Yen and
Cent, you are not set up for Scandinavian characters. If your system is set up correctly,
they should look like an 'o' and an 'O' overwritten by a '/'.
To read or create non Roman web pages or email, you may be required to have
these special fonts installed in your computer.
The code telling your computer what to display, may also contain information about
where to put characters and what colors to use.
An online service may order your computer to display a given character in column
10 on line 2, and to print it in blinking red color. If you are not set up correctly, these
codes may show as garbage on your screen rather than as a colorful character in a given
position.
If you call a service set to display text in VT 52 format, and your communications
program is set accordingly, then you should be OK. VT 52 is a setup that makes a
program or a service 'behave' like a DEC VT 52 terminal.
Being able to view VT 52 coded text on your screen, does not guarantee that you
can capture this 'picture' to a file on your disk. Your communications program may need
special features to do that. If these features are missing, you are in for a surprise. The
text in your capture file may look like in this example (on my computer, it came on a
single, long line ):
**H*J*Y"4 Innhold*Y%>
*Y&4Emneoversikt 1 Brukerprofil 6*Y)
4Stikkord A ] 2 Bruker *Y*4 veile
dning 7*Y,4Informasjons
*Y 4leverand|rer A ] 3 Teledatanytt*Y.W
8*Y04Personlig indeks 4*Y2H *Y3
4Meldingstjenesten 5 Avslutte9*Y64 ]pningsside
*00# *Y 4TELEDATA 880823 1538*
Y74 NTA01 00a*Y74
*Y74*Y74
The character '*' in this example refers to the ESCape character (ASCII number 27).
ESC is used to tell your computer that what follows is a VT 52 display command. The
codes following ESC say where text is to be printed on your screen (from line number x
and column number y).
If your communications program cannot save VT 52 coded text in a readable way,
you'll need auxiliary programs to remove or convert the codes. Some communication
programs let you take snapshots of the screen, and store the result in a file. This usually
gives good results, but it may be a cumbersome approach.
Minitel (in France and the U.S.) belongs to a group of online services called
videotex (or viewdata). They believe that beautiful color graphics, large characters, and
menus give them a competitive advantage.
Viewdata services use graphical display standards with names like CEPT, Captain
(Character and Pattern Telephone Access Information Network System), Telidon,
Minitel, Teletel, GIF (the Graphics Interchange Format), Viewdata, and NAPLPS (The
North American Presentation Level Protocol Syntax).
Often, you'll need special terminal machines to use viewdata services. On other
services, you must use special software plus an emulator card in your computer.
Many MS DOS based bulletin boards let you set access defaults to colors and
graphics. Most of them use ANSI graphics in welcome texts and menus. Users must set
their programs to ANSI (or ANSI BBS) to take advantage.
Capture these welcome texts and menus to a file on your hard disk, and view them
with an editor. They are filled with ANSI escape codes, and thus hard to read or search.
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