Atari 65XE Owner's Manual page 94

PROTECTING YOUR PROGRAM
Ever wonder how you could protect your programs from prying eyes
and quick fingers? A couple of programming tips can help keep
pilferers out of your programs.
First type in this program:
10 FOR X=1 TO 50:POKE 710,X: NEXT X:GOTO 10
To protect the program, add another program line to disable the
key. This line prevents someone from breaking into the
program and listing it while it's running. Also, if you design a program
that requires keyboard entry, disabling the
"finger slip," that dreaded mishap when your finger accidentally hits
the key and brings your program to a screeching halt.
Delete GOTO 10 from the colorful program and add this line:
20 POKE 1 6 , 6 4 : P O K E 5 3 7 7 4 , 6 4 : G O T O 10
Now run your new program and try to stop it by pressing the
key. You can't get into it.
To be effective, the POKE statements must be inserted in your
program after each graphics mode command.
Disabling the
will figure out that he or she can break into your program and list it by
simply pressing the
program:
5 POKE 580,1
Now when the inquisitive intruder presses
program is purged from the computer's memory—no program, no
listing! The POKE statement should always be at the beginning of your
program.
key has its limitations. Some smart programmer
key. To foil this culprit, add this line to your
89
key protects against
, the flashing colors