Hi, New just now to this site and have a question... I am very interested in the seed/key algorithm. I began to write a program to do an automatic decode. The line "• 0x2A = Complement – if HH>LL use 2’s complement, else use 1’s complement" agrees with what I have done, but later in the document the line "Thus, given the seed 0x1234: a) ~0x1234 = 0xEDCB b) 0xEDCB ROR 3 = 0x7DB9 c) 0x7DB9 " shows him using a 1s complement. I believe the calculation is off. Hope this thread is still active.
Also wonder if a '97 Camaro 5.7 would be covered by one of the algorithms. If yes which of the 256. I have worked out where the seed and key is stored in the internal HC11 EEPROM. Just need to find a way to access it.

Hope there is still interest in a key gen...

Tom