|
|
|
IDENTIFICATION SERVEUR : 51.83.10.22 - CLIENT : 3.215.182.81 |
|
| Voir le sujet précédent :: Voir le sujet suivant |
| Auteur |
Message |
toinet
Site Admin
Inscrit le: 15 Juin 2007
Messages: 3043
Localisation: Le Chesnay, France
|
 Posté le: Jeu 13 Sep 2007, 12:42 Sujet du message: Elite (Firebird, 1985) |
 |
|
Elite is a well-known strategic space simulation (it is written on the box) edited by Firebird.
PROTECTION TYPE
It is a standard 16-sector disk with the following markers:
- Header: D5 AA 96 / DE AA
- Data : D5 AA xx / DE AA
THE PROTECTION
The disk uses a standard DOS and some tracks and sectors are copyable but some others are not. A BLOAD or a BRUN command calls a routine that updates the third data marker depending on the filename.
The pseudo-code is the following:
| Code: |
A <= GET LAST CHARACTER OF FILENAME
X <= GET INDEX OF LAST CHARACTER OF FILENAME
X <= X + (A AND #$1F)
$31 <= GET NIBBLE FROM AUTHORIZED NIBBLES,X
|
That is the first program I see using that kind of protection. It is a funny one.
Let's now get the marker related to the filenames:
| Code: |
E.LITE => index is 5, character is E, then data marker is BB
E.LA => index is 3, character is A, then data marker is B4
S.EC3 => index is 4, character is 3, then data marker is DA
|
DISK COPY
There are several methods to copy the disk:
1/ Use a bit-copier to get an image of the protected disk
- Elite's disk is write protected, that will prevent you from making a hole on the disk
- Then edit T11/SF and rename the E.LITE file so that the DOS boot will jump to the prompt, allowing you to BLOAD the different files and copy them onto another disk.
2/ Use DiskFixer
- First of all, copy the disk with Locksmith. There will be read errors which are due to the change of marker
- Then launch DiskFixer, insert the original Elite disk on drive 1, the copy on drive 2
- Use the D command to display the directory and follow the different files described above
- Note that you will have to replace the third data marker with the Options menu
- Each sector read from the source drive must be copied to the second drive (option C)
3/ The easiest way
Just patch the data read routine of the RWTS:
- Launch Advanced Demuffin, go to the monitor
- B8FD: C9 AD D0 E7 => C9 AD D0 00
- CTRL-Y
- Copy the disk
COPY A NEW DOS 3.3
I have decided to replace the old DOS of Elite with an official version from Apple (thanks to Deckard for providing me with the original master disk):
- Launch Advanced Demuffin or Locksmith
- Copy the first three tracks (T0/S0 to T2/S4) from the Master disk to your copy of Elite
- Launch Copy II Plus 5.x
- Change the boot program of your Elite disk, it must be the E.LITE file
That's it! A funny one, it could have been differently (so many ways) but that was fun using different tools instead of doing it the easiest way!
Toinet |
|
| Revenir en haut de page |
|
 |
|
|
Vous ne pouvez pas poster de nouveaux sujets dans ce forum
Vous ne pouvez pas répondre aux sujets dans ce forum
Vous ne pouvez pas éditer vos messages dans ce forum
Vous ne pouvez pas supprimer vos messages dans ce forum
Vous ne pouvez pas voter dans les sondages de ce forum
|
|
FAQ 
Rechercher 
Liste des Membres 
Groupes d'utilisateurs
S'enregistrer
Profil 
Se connecter pour vérifier ses messages privés 
Connexion 
