Originally posted by code65536
[B]Just change 60 02 C3 to D3 D3 D3. Hey Nic, out of curiosity, do you even know what that does? :rolleyes:
So before people get so excited about this ingenious finding of Nic...
1) The above simply disabled a subroutine in the firmware that checks to make sure that the EEPROM is the right EEPROM (i.e., a 832S EEPROM instead of a 812S EEPROM).
2) Saying that this is the only change--just tweaking the firmware and leaving the EEPROM alone--means that the 812S and 832S EEPROMs are the same except in the way they identify themselves.
3) In fact, this is hardly original. The 451@851, 812@851, etc., "mods" all work by just disabling the EEPROM check. Just what LDW851FP does. Just that terminal's and c0deking's hacked firmwares do.
4) Oh, incidentally, this is what happened with the Polish mod for the 411. They killed the EEPROM check, didn't bother to change anything else, and their mod failed miserably.
5) Finally, if you really knew what you're talking about, you'd KNOW that your method won't work. It has already been said that EEPROM changes need to be made. And given the current prevalence of not tweaking the EEPROM unless necessary (like the 451@851 mods--if we can just disable, then go with it), why would it have been said that it's necessary?
So folks, before you get too excited about Nic's contribution, here's a bit of him unmasked. Trying to steal the thunder by coming out with the Nic-inspired mod. Well, congratulations; you've just demonstrated that you really don't know what you're talking about. [/B]
To answer your question yes I know what it does, and I argue that it does not work, the failures afaik were caused by wrong eeproms being used, or vastly different eeprom values between models, in this case the eeproms values look to be the same, only checksums differnt. I have also just finished working out the checksum values and have it completed for the 812s and 832s drives. I updated the checksummer and tested it on a 812s -> 832s and it works fine. (DL burns excepted of course)
for those in the know, apply a standard 811s checksum algorithm calculation, then xor the final values from 100h, 105h, 10ah and 10fh with 0xF4, apply those changes to the eeprom.
To recalculate for a 812s, do the same but skip the xor as the checksum for 812s is identical to the 811s