Re: hp85 secured files
Message #3 Posted by Ex-PPC member on 15 Feb 2003, 9:51 p.m.,
in response to message #2 by David Smith
David Smith wrote: "With two digits, there are not that many combinations to try... sit down with some good beer and start poking..."
With two digits, on the HP-85, you have as many as 256*256 = 65,536 possibilities to try per program, assuming all have different combinations. That's a lot.
Besides, if the programs are stored on tape, each attempt will mean reading the tape and possibly rewinding. The tape will wear out and become damaged much sooner, so trying all combinations is definitely out of the question, unless you're extremely lucky. The same would apply for programs stored on a floppy disk, it would also get ruined.
The best way would be if someone knows the combination and will tell. That failing, I think the proper way to do it is to get an 'UNSECURE' binary program, load it using LOADBIN,
then using it to remove the protection. Such a binary can probably be found in libraries or repositories of obsolete HP software and hardware. Else, you can write it yourself if you get the Assembler ROM or its tape version (which included a BASIC program to do the editing & compiling, and the binary program STOREBIN to convert your assembler source code to a binary program and store it on tape), plus the relevant documentation.
Perhaps some visitor has some of these materials available, knows where they can be found, or can shed some light on the subject. I used to have all of them, but that was many, many years ago ...
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