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Finding run/init addr's on packed xex/exe or com files

Posted: Wed Apr 19, 2006 9:52 am
by carmel_andrews
I am try ing to find the run/init addresses (using atari800wins+ built in monitor) for various xex/exe and com files i've downloaded from the internet

i know that the locatipons used are 2/3,a-d and 2e0-3

the files i have problems with are mostly those european/polish games that are heavily packed, like robin (hawkeye clone) whoops 2 etc

What seems to happen is that the depacker routines seem to mask out the proper or real run/init addr, or over write it,

I do have a pc util called dissassembler 6502 by erich backer/bacher ( i think) however that program has a limitation of binary files under 256 segments

The other thing is is that it's almost impossible to view the dissassembler listing as the file/segment is packed so you can't see where the program is run/init from plus the fact that the dissassembler program doesn't have a search feature (which would be usefull)

although the dissassembler program does list the 2e0-3 locations, they mostly if not only refer to the run init addresses for the depack routines and not the program itself

Is there a program or utility out there that will unpack these files and put the data/segments back into their proper/actual mem locations

Or do these program's run/init addresses execute in 'high memory' (i.e above bfff) which means that you can't execute/initialise or hack the file out, as you would effectively be executing/initialising o/s routines

Re: Finding run/init addr's on packed xex/exe or com files

Posted: Thu Apr 20, 2006 11:47 am
by Andre
carmel_andrews wrote: Is there a program or utility out there that will unpack these files and put the data/segments back into their proper/actual mem locations
Yes, just load the atr-file with your emulator and use the built-in monitor; find the DOS routines and set breakpoints accordingly. Don't ask me for details - I forgot nearly everything meanwhile.

re: finding run/init address for packed xex/exe files

Posted: Thu Apr 20, 2006 3:40 pm
by carmel_andrews
where's twaugs mapping the atari when you need it

Posted: Thu Apr 20, 2006 6:37 pm
by deathtrappomegranate
If you mean "Mapping the Atari" by Ian Chadwick, it's here:

http://www.atariarchives.org/mapping/