Unprotect Deep Space by Sirtect Software by Independent (IND)
10720 of 48,815 files
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This download is an executable MS-DOS program that will not run on a modern computer.
It needs a DOS emulator such as DOSBox-X, Staging;
or a virtualized MS-DOS or FreeDOS system.
Browsers may flag this download as unwanted or malicious. If unsure, scan it with VirusTotal. -
Last modified Jun 21, 2015 10:48:17 PM
MD5 checksum 30ce1d33a6b452086341c6a8f6847cd2
Mime type Zip archive data
Download DEEPSPAC.zip
Size 1 kB
1987 October 29
- Zip - DOS / Guides and how-tos
- Popcorn Man, writer credits
3 items in the archive
- DEEPSPAC.UNP
- DSZAP.BAT
- DSZAP.DAT
To unprotect DEEP*SPACE (Operation Copernicus) by Sirtech Software:
Copy all files from your master disk to another disk (or your hard disk).
Copy the files DSZAP.BAT, DSZAP.DAT and DEBUG.COM (from your DOS disk) to
the same disk. Type DSZAP from the DOS prompt. An unprotected version
of DS.EXE will be created, called DS2.EXE. This can be run from a floppy
or hard disk and will not check for your original disk in drive A:
All that the original program does is check for the presence of sector
number 80 on track 27 of the master disk. The zap batch file NOP's out
these checks.
Note: this unprotect works fine on my version of DEEPSPACE. My copy has the
following files (and dates) on it:
DS EXE 70656 8-14-87 12:50p
LAND PIC 16384 12-29-86 7:27p
LEFT PIC 16384 2-26-87 2:32p
LS PIC 16384 2-05-87 12:31p
RIGHT PIC 16384 2-28-87 5:59p
TITLE PIC 16384 12-29-86 7:27p
If your version is different, this Unp probably won't work. In case this
happens, I've listed the changes made to DS.EXE below:
C>debug ds.zap
-r
AX=0000 BX=0001 CX=1400 DX=0000 SP=FFEE BP=0000 SI=0000 DI=0000
DS=2462 ES=2462 SS=2462 CS=2462 IP=0100 NV UP DI PL NZ NA PO NC
2462:0100 4D DEC BP
-s 0 l fffe cd 13
2462:0315
2462:032C
2462:0337
-u 313 353
2462:0313 33C0 XOR AX,AX
2462:0315 CD13 INT 13 - change to NOP NOP
2462:0317 BF0500 MOV DI,0005
2462:031A BE0104 MOV SI,0401
2462:031D BB0090 MOV BX,9000
2462:0320 8EC3 MOV ES,BX
2462:0322 33DB XOR BX,BX
2462:0324 B90127 MOV CX,2701
2462:0327 BA0000 MOV DX,0000
2462:032A 8BC6 MOV AX,SI
2462:032C CD13 INT 13 - change to NOP NOP
2462:032E 7303 JNB 0333 - change to JMP 0333
2462:0330 4F DEC DI
2462:0331 75F7 JNZ 032A
2462:0333 8BC6 MOV AX,SI
2462:0335 B180 MOV CL,80
2462:0337 CD13 INT 13 - change to NOP NOP
2462:0339 5F POP DI
2462:033A 5E POP SI
2462:033B 07 POP ES
2462:033C BE0800 MOV SI,0008
2462:033F 7203 JB 0344 - change to JMP 344
2462:0341 E92C76 JMP 7970
2462:0344 A90010 TEST AX,1000
2462:0347 7503 JNZ 034C - change to JMP 34C
2462:0349 E92476 JMP 7970
2462:0354 A1F14B MOV AX,[4BF1]
2462:0357 0B06EF4B OR AX,[4BEF]
2462:035B 7506 JNZ 0363 - change to JMP 0363
2462:035D BED109 MOV SI,09D1
2462:0360 E90D76 JMP 7970
If you'll notice, there's a series of error checks. If something doesn't
match, the program jumps to 7970 (naughty,naughty message, followed by crash
and burn.
Enjoy!
Popcorn Man 10/29/1987