Laurence Gosalves's answer is correct insofar as your game, Bez Milosti, is concerned, since it looks like the game is written either in machine language or in compiled BASIC. However, not all text adventures which, when listed, simply show an SYS
command, are like this. Sometimes the game really is distributed as interpreted BASIC, the source code for which is initially hidden but gets decrypted or decompressed by a short machine-language routine.
You can verify this for a given game by LOAD
ing (but not RUN
ning) it, LIST
ing it, and then using a machine-language monitor (such as the one built into VICE) to disassemble the memory starting at the SYS
address. Or, even if (like me) you're not adept at reading 6502 assembly language, you can try RUN
ning the game and then dumping memory at $0801, which is the start of BASIC. If you see what looks like variable names and the contents of strings or REM
arks, then the game is indeed decrypted or decompressed BASIC. At this point you can use the monitor to re-enable the RUN/STOP key (> 0328 ED
in the VICE monitor), use that key to stop the program, and then LIST
or SAVE
it to disk. (Note that many such programs also disable the LIST
command, so you may need to first re-enable it with > 0307 A7
from the monitor or POKE 775,167
from BASIC.)
An example of a commercially distributed BASIC game that uses this compression technique is Tombs of Xeiops. If you LIST
the game after LOAD
ing, all you see is this:
239 SYS2061
However, after running the game, and then re-enabling RUN/STOP and LIST
via the VICE monitor, the game can be stopped and listed:
BREAK IN 3054
READY.
LIST
1 GOSUB 3150:CR$=CHR$(13):CP=1
2 GOSUB 2230:VA$="IT LOOKS VALUABLE TO ME":FC$="THE CAT IS FRIGHTENED"
3 I1$="YOU NEED A DIRECT OBJECT":S3$="I DON'T KNOW THAT WORD"
4 S1$="I CAN'T SEE IT HERE":IM$="THAT'S IMPOSSIBLE":WD$="IT IS NOW PITCH DARK"
5 W1$="THE LIZARD SEES THE CAT AND FLEES":SR$="A SILKEN BELT FALLS AT YOUR FEET"
6 GOSUB 5000
7 IFKTTHENOB%(29,0)=CP:IFCP=6THENKT=0
8 IFKTTHENPRINT"{DOWN}THE WATCHER OF THE TOMBS FOLLOWS YOU"
10 GOSUB 390
11 IFN1$="DESERT"ORN1$="SAND"THENPRINT"IT'S JUST A LOT OF SAND":GOTO10
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