Author Topic: Unprotecting basic games loader protected.  (Read 1921 times)

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Offline dragon

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Unprotecting basic games loader protected.
« on: 13:28, 11 June 16 »
Hello, anyone know how deprotect basic loaders?.

I take a look to north &south  tape, but i think it have basic code camuflated, not assembler. But i not know about  the basic protections.

I need it to know where the program is loaded.

north & south - les tuniques bleues &copy infogrames (1989)
north & south - les tuniques bleues &copy infogrames (1989) (split version).

Offline AMSDOS

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Re: Unprotecting basic games loader protected.
« Reply #1 on: 13:42, 11 June 16 »
Hello, anyone know how deprotect basic loaders?.


There's a program from AA53 type ins that deprotects basic files.
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* I also like to problem solve code in BASIC :)   * And type-in Type-Ins! :D

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Offline dragon

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Re: Unprotecting basic games loader protected.
« Reply #2 on: 13:50, 11 June 16 »
AA53 = amstrad action number 53 maybe?.

Offline AMSDOS

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Re: Unprotecting basic games loader protected.
« Reply #3 on: 13:52, 11 June 16 »
AA53 = amstrad action number 53 maybe?.

Yeah that's the one.
* Using the old Amstrad Languages :D   * with the Firmware :P
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Offline SuTeKH/Epyteor

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Offline dragon

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Re: Unprotecting basic games loader protected.
« Reply #5 on: 14:04, 11 June 16 »
Thanks all, but i not speak about of protected basic files with ,p

The file is unprotected. But when i made a list. Y only displays lines from 5 to 0 with a copyright of the game text . I thing the rest are in basic but hidden. I search view all code :) .
« Last Edit: 14:06, 11 June 16 by dragon »

Offline Joseman

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Re: Unprotecting basic games loader protected.
« Reply #6 on: 14:06, 11 June 16 »
Hello, anyone know how deprotect basic loaders?.


If you are deprotecting under windows and emulators there is a trick that is use "ManageDsk" it has a fancy option that let you list the file on varios format "asm", "Basic", "scr"...

ok, you have to put the tape loader on disk... but for some nasty basic loader (with no lines or lines that were erased for listing, or any bin loader into a basic loader, etc)  take a look of the listing that managedsk does is very very interesting sometimes...

Offline dragon

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Re: Unprotecting basic games loader protected.
« Reply #7 on: 14:17, 11 June 16 »
If you are deprotecting under windows and emulators there is a trick that is use "ManageDsk" it has a fancy option that let you list the file on varios format "asm", "Basic", "scr"...

ok, you have to put the tape loader on disk... but for some nasty basic loader (with no lines or lines that were erased for listing, or any bin loader into a basic loader, etc)  take a look of the listing that managedsk does is very very interesting sometimes...

Perfect thanks!


5 :' 
4 :'     NORTH & SOUTH
3 :' (C) 1990 BY INFOGRAMES
2 :'   AMSTRAD VERSION BY
1 :'      NEW FRONTIER
0 :'
16713 IF PEEK(375)=77 THEN GOTO 110
20600 BORDER 0:PAPER 0:PEN 1:INK 0,0:INK 1,26:MODE 1:LOCATE 1,25:PRINT "Loading..."
36555 MEMORY &3FFF:LOAD "!",&4000:CALL &4000
100 STOP
110 :'
120 :' MASTER MAKER TAPE
130 :'
140 MEMORY &7FFF:LOAD "NORTH",&8000
150 RESTORE 200:READ DIR,VALOR
160 WHILE DIR<>-1
170 POKE DIR,VALOR:READ DIR,VALOR
180 WEND
190 ├╣TAPE.OUT:PRINT "Insert tape & press any key":CALL &BB18:SAVE "!NORTH":SAVE "!& SOUTH",B,&8000,&C00,&8000:LOAD"domaster":CALL &D000
200 DATA 375,32,370,5,379,4,404,3,434,2,462,1,487,0,485,35,486,21,492,85,493,82,494,73,495,65,517,32,518,45,519,120,520,80,572,43,573,66,574,203,575,142,-1,-1

Offline Devilmarkus

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Re: Unprotecting basic games loader protected.
« Reply #8 on: 20:13, 12 June 16 »
JavaCPC has the "Ignore ,P protection" option in system-configuration ;)

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Offline Shining

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Re: Unprotecting basic games loader protected.
« Reply #9 on: 14:29, 14 June 16 »
If someone is interested how to protect basic listings like this, here is a short description how I did this for my stuff in the 80s:


As you may already know, the first basic-line in RAM begins at 0x170. First two bytes represent the length of the line.


A short basic-program:
Code: [Select]
10 'This is a little basic-protection demonstration
20 pen 3
30 print "The code is still here"




Now you need the length of the first byte for later deprotecting the file.
type: print peek(&170) to get the value (in decimal). In our case the result is 54.
You don't need to, but if you also want to manipulate adress &171 (second byte of the line-length), you need to peek this too.


You are ready now to protect your listing.
type: poke &170,&A


I mostly used 0x0A (LineFeed) because it gets a fancy result. But you are free to use any number between 1-255.


When you now type list, you'll get the following result:
Code: [Select]
10 'This is a little basic-protection demonstration
8307 a little basic-protection demonstration

But when you type run, oh wonder, the code is still there.

You can also patch the second byte of the length if you want.

What I did also was the following: I patched the line-number, too:
poke &172,255 (for example)
(and if you want &173)

Sometimes I had the case that a complex basic-program did not work after patching. So I included following first line after the comments:

15 POKE &170,37:POKE &172,5:POKE &BDEE,&C9:KEY DEF 66,0,0:CALL &BC02

(The 37 and 5 for the two pokes are only examples in our case here it's 54 (from the peek) and 5 for the correct line-number)

Here I patched back the basic-file and prevented pressing ESC.

Perhaps this stuff's useful for someone....
« Last Edit: 16:44, 14 June 16 by Shining »
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