Rgbi Monitors; Dual Monitors; Using Prepackaged 80-Column Software; Creating 80-Column Programs - Commodore 128D User Manual

Using
Prepackaged 80-
Column Software
Creating 80-
Column Programs
RGBI Monitors
Dual Monitors
RGBI monitors are specially designed to display
80-column output. Although RGBI stands for
Red Green Blue Intensity, RGBI monitors can be
either color or monochrome (single color). The
most popular monochrome monitors use green
or amber displays. An RGBI monitor connected
to the RGBI port can handle 80-column output in
both C128 and CP/M modes.
Dual monitors like the Commodore 1902 can
provide either a composite video (40-column) or
RGBI (80-column) display. A dual monitor con
nects to both video ports. A switch on the moni
tor lets you select either screen output. The 40/
80 key on your computer determines the type of
screen display upon power-up. Make sure the
40/80 key setting corresponds to the 40/80
column slide switch setting on the front control
panel of the monitor. NOTE: You can still switch
back and forth between 40 and 80 column out
put by pressing and releasing the ESC key and
then pressing the X key, regardless of which
position the 40/80 key is in.
Most CP/M programs utilize an 80-column screen, as do many of the
other buisness 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 pro
grams 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.
In addition to running prepackaged software, the 80-column screen
width can be useful in designing your own programs. You've proba
bly 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. In general,
an 80-column screen allows for a clearer screen and better
organization.
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USING C128 MODE—Using 80 Columns