Commodore CBM - 5 Making the most of PET Features; Keyboard Rollover

CHAPTER 5
Making the Most of PET Features
ln this chapter we go over features of the PET that vou will come across
sooner or later in your
PET BASIC programs. Where the "feature" is a limitation or
other stumbling black. we tell vou how ta get around it (if possible) or at least
warn vou about it. Where the feature is a real capability, we tell vou how ta use it
ta its fu Ilest adva ntage.
KEYBOARD ROLLOVER
If vou type rapidly vou may type faster than the characters can be printed. If
vou press two or more keys simultaneously or press the second key before the
first character
is printed. a keystroke will be ignored - unless your keyboard has
"rollover." Rollover "remembers" a keystroke until it is printed. Fortunately, the
PET keyboard has rollover.
Rollover remembers incoming keystrokes while a preceding keystroke
is being processed. The "remembered" keystrokes are then processed. The
keystrokes are remembered by storing them in a butter until they are printed:
Press Keys
#1
Bulfer
~ f
PET
and
-.....
Character # 1
Screen
#2
Character #2
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