Audio Cassette formats; Copy protection? - test-drb@ccmp.vtda.org

1 Dec 1998

...
 ::There are plenty of ways of preventing a BASIC
program from being listed.
...
 ::Dunno how you prevent it being saved (and say
'BAD PROGRAM'), but I could
...
 ::probably figure it out given time... Anyone else?

 On the 64, you could type

 10 remL

 (rem, then a shifted-L)

 and LIST will stop up with a ?SYNTAX  ERROR when it hits that line. Rather
...
  easy to defeat but annoying as heck. :-) 
Same on Basic 2 PETS.  On BASIC 1 you used shift-K.

Possibility that I thought of, but didn't try.  Make the initial line a v.
high line number (>63999).  Have the program start rem L, then disable the
stop key, then poke that line number to something smaller.  Bit harder to
defeat but won't deter the determined cracker.

Mean trick I did use.  In the middle of a subroutine I entered the line

REM@TURN

I then found the @ sign and poked the location with 20 (ctrl-T, the PET
backspace)

This now lists as RETURN but does nothing...

Philip.