Using Prepackaged 80 Column Software; Creating 80 Column Pr O G R A M S; Using 40 And 80 Columns Together - Commodore 128 System Manual

USING PREPACKAGED 80-C0LUMN SOFTWARE
Most CP/M programs utilize an 80-column screen, as do many of
the other business application packages you can use in C128
mode. Since the width of a normal printed page is 80 columns, an
80-column wordprocessor can display information on the screen
exactly as that information will appear on paper. Spreadsheet
programs often specify an 80-column format, in order to provide
enough space for the necessary columns and categories of
information. Many database packages and telecommunications
programs also require or can use an 80-column screen.
CREATING 80-C0LUMN PROGRAMS
ln addition to running prepackaged software, the 80-column
screen width can be useful in designing your own programs.
You've probably noticed what happens when you type a line that
is wider than 40 columns on a 40-column screen. The lines
" wrap around" that is, they continue onto the next screen line.
This may cause confusion in reading the line, and can even lead
to programming errors. An 80-column screen helps eliminate
these problems, ln general, an 80-column screen allows for a
clearer screen and better organization.
USING 4 0 AND 8 0 COLUMNS TOGETHER
The main advantage of 40- column composite video output is the
availability of bit mapped graphics, while 80 columns gives you
output for word processing and other business applications. If
you have two monitors, you can write programs that are "shared" ,
using the text features 80 columns affords you and the graphics
of 40 columns. A special command, (GRAPHIC 1,1 ) can be used
within a program to transfer the execution of graphics commands
to the 40-column display. If you have a dual monitor (one that
can display both 40 and 80 column formats) you can place
GRAPHIC 1,1 statements in your program so that graphics will be
output in 40-column screen format, ln order to view the graphic
output, however, you will need to change the video switch on the
monitor to 40 columns. If you write a program like this, it might be
a good idea to include on-screen directions to the user to change
the video switch.
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