Deprotecting Carmen San Diego programs: -------------------------------------- It is not surprising that the program is copy-protected. But again, the protection scheme is the same as other earlier Broderbund products: Track 20/21 nibble count scheme. Disk 1 (/Carmen.World1) is really just a copy of the System Disk and is copyable. You probably want to use your own System Disk instead. The protection is on the main file Carmen.World of Disk 2 (/Carmen.World2). I used ProSel's Block Warden for the deprotection process. My purpose was not trying to decipher exactly how the protection code was done in detail, but to achieve the deprotection itself. I found the sequence A2 20 A0 01 on the second block of Carmen.World, which proved to be quite convenient. I located the beginning and the end of this particular nibble counting routine, which told me two things: a) this routine started at offset 0212 from the beginning of the main code segment, and, b) this routine ended with an RTL instruction, indicating that it was JSL'ed from somewhere. Next I searched for the sequence 22 12 02 (JSL xx0212) and was rewarded with one occurrence only. Again I located the beginning and the end (again an RTL) of this particular routine. It was then a simple matter of planting an RTL at its beginning, effectively bypassing the whole thing. Step by step procedure follows: 1) Make a copy of Disk 2 /Carmen.World2 2) Make the following change on the copy: Block Byte From To -------------------------------- $67 $22 0B 6B Note that Block $67 is the relative Block 96 (decimal) of the file Carmen.World (in case you use Block Warden). You can search the following hex string: 6B 0B 3B 38 E9 F9 00 5B 69 E4 00 and change the second byte from 0B to 6B. 3) Write the block back to the disk.