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- Silent Service Unprotect (TMH)
-
- 1. Copy the original Silent Service disk using DOS Diskcopy.
- 2. Load Debug.com from your DOS disk ( A>DEBUG ).
- 3. Place the Silent Service copy in drive A.
- 4. Use the following commands after you see the Debug prompt:
- a. -L 0 0 9 5
- b. -E 91E 08
- c. -W 0 0 9 5
- e. -Q
-
- That's it! Boot up and enjoy!
-
- ************************* Also ***********************
-
- ********NEW COPY PROTECTION VERSION:*********
-
- If the unprotect listed above doesn't do the job, try this:
-
- Copy the master disk, load debug as listed above, put Silent Service
- copy in drive A:
- Use the following commands from DEBUG:
- (a) -L 0 0 D 1 {load absolutek sector 13 from disk}
-
- (b) -U 170 {disassemble some code}
- You should see:
- 2488:0170 B50A MOV CH,0A
- 2488:0172 B600 MOV DH,00
- 2488:0174 B200 MOV DL,00
- 2488:0176 03C3 ADD AX,BX <-- {during execution, this changes to
- 2488:0178 80FC00 CMP AH,00 INT 13}
- 2488:017B 7409 JZ 0186
- Note that you might have some other number than 2488: - this is OK.
- If your disk doesn't match, you're probably out of luck -this might not
- work.
-
- (c) -E 017B EB 09 {change the JZ to a JMP - fake it out}
-
- (d) -W 0 0 D 1 {save the changes to disk}
-
- (e) -Q
- You should now have an unprotected copy. Enjoy!
-
- Jeff Johnson 2/7/87
-
- ************************* Also ***********************
-
- SOFTWARE PIRATES INC.
- presents
-
- Silent Service Unprotect
-
- This file will tell you how to unprotect "Silent Service" by Micro
- Prose. To complete this unprotection you will need the following:
-
- 1. A good copy program like BACKUP.EXE or COPYIIPC.EXE.
- 2. FIXSS.COM included in the package.
-
- BACKGROUND: The copy protection scheme used by Micro Prose on Silent Service
- is very good. I have found no commercial copy program that can
- make a usable backup copy of this disk. The Silent Service master
- disk has track 10 specially made. Track 10 has 16 sector ids on it
- instead of the normal 8 or 9. Using COPYIIPC, track 10 will be
- reproduced with only 10 ids on it. When Silent Service boots up it
- verifies that all 16 sector ids exists. The sectors on track 10
- contain no usable data. Silent Service just makes sure that they
- exists. Knowing this we can go in and patch Silent Service so that
- it doesn't check track 10 at all. After patching the program we
- can go in and re-format track 10 to normal sector size. Finally,
- the makers on Silent Service, did one more little trick to prevent
- DISKCOPY from working. On track 12 side one, the sectors are in
- sequential order. This screws up DISKCOPY into thinking the disk
- drive door is open, when it is not. We must re-format the track to
- normal and put the data back. Also, just for kicks, we observed
- that there was no FAT table on this disk, but that the space where
- a FAT table would go was not used, so we put a FAT table out there.
- The will make the disk look like it really is a double-side 8
- sectors/track disk to DOS. This allows DISKCOPY to know how the
- disk is formatted. With this done, you will have a working copy of
- Silent Service that can be copied by DISKCOPY.COM.
-
- Now I realize that most of you probably won't understand most of
- what I just said up there. That's OK. We provided a small program
- FIXSS.COM that does most of the work for you.
-
- Step 1: Make a backup copy of your master Silent Service disk. Your copy
- program must be able to handle non-DOS sector sizes. Norell BACKUP or
- Central Point COPYIIPC can do this. Remember to copy both sides of
- the disk, Silent Service is double-sided. Once you have copied the
- master disk put it away. You will not be needing it again.
-
- NOTE: The backup copy just made will not function ... yet. When you are done
- with Step 2, the disk will be DISKCOPYable.
-
- Step 2: Put copy of Silent Service into drive A. Then execute the FIXSS
- program. This program will make all the patches to the game for
- you. When it has completed you will have a DISKCOPYable version of
- the game.
-
-