Necro bump!

Don't you hate it when someone asks a question and then posts something like "fixed" or "solved" without describing the actual fix? I surely do!  

Anyway, I wanted to play with EEPROM in my ME7.1.1 ECU. Since I already have the R-box disassembled and defined, I went to take a look at it (thanks, sweegie!). I then cheated and did a very "ghetto" thing (not proud): simply found the similar pattern in my BIN (well, looking in approx the same memory region). Then I went and read it with ME7L in my car and it indeed was spot on! With one minor exception: EEPROM is mapped not in a direct or raw way. What I mean by that is: RAM image starts from the second EEPROM page (first one is skipped), there are no "backup" pages either.

Here's the pic of the "reference" structure from IDA (for ME7.1.1 anyway):

I have since found out that it's quite easy to find the reference to start of ME7 EEPROM memory mirror by looking around "VARCODE" functions. They are quite easy to backtrack by looking where "vkASRantrieb" (picked up by me7info) is written to. Then you go couple of function X-REFs back, scroll to the bottom and find:


That reference is usually picked up by IDA as just a hex offset, you have to press "o" to get it to display like a memory var.

RE: the checksum - didn't really play with it, but there already should be a function to correct it. So it's much easier to find and call it, than write your own routine.

_{We're also a bit offtopic here, since the thread title says "MED9".}

I agree, but great info! Nyet, can you split this to a new me7 eeprom thread?

I have found out that it is not possible to write the eeprom by altering the ram mirror. It seems to be a slave of the eeprom, after power off it copies those values again. I am currently trying to disassemble lemmiwinks to find out how they get their program to find the adaption blocks. I have never used that program before, but it works okay for quick placing of odd values in the eeprom

Have you tried to fix the checksum after modify a position of the mirror? Work of similar way than MED9 ??