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kinda a lurker in here, but i've been watching alot of what you have to say. this question is mostly for calum but if anyone elses understands be sure to chime in.
well ive been reading up alot on the sr20 ecu, i found a bunch of old posts refering to the motorola clone mirco controller used in these ecus and am wondering if anyone has found the operational code data sheets or anything similar. I do alot of hobbyist PIC programming as well as having an EE and CE university degree. i know a ton is involved in reworking the old ecus, and i plan on changing that which will require an even greater amount of research and planning as well as work.
what i plan to do is reverse the hex data inside a stock rom into a bastardized version of the original source, this would be done using a piece of software which i plan on writing that will parse through a rom file and pair the source data that matches with hex information where the software sees a possible match. now this software will be 'smart' so to say as it will recognize common areas of the program memory and associate the most likely variable names with ones that will be set up to provide the user a somewhat clear representation of the original source data. this is very challanging to do as not all data in program memory is operational, some of coarse is used for addressing which will add the constraint that the software must recognize te difference between either.
the reason for my request of the op code referecnce is that without this it will complicate the task even farther as i will have to use additional programming to stub the micro controller itself. and if this proves to be impossible i will need to build an entire ecu from scratch, which is not much more daunghting than what i already have planned
once this is done i hope to produce boards that will be complete swap-outs for original equipment and use newer and more powerful controllers that will will not only be fully customizable as far as the current needs of the automotive hobbyist, but allow for new innovation that will not be limited by the inabilitly to alter the ecu in its entirety.
any input on the subject is greatly appreciated, and if anyone wants to mash brains on this lemmie know
I'm pretty sure I saw some floating around. I remember something about the microprocessor used was more of a private version based off a public version (if that makes any sense). Let me see what I can dig up.
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I think your barking up the wrong tree, but I'll supply the manual. If you want to change the hardware I think your better off ditching everything and starting from scratch, ala megasquirt or whatever. If you just want to make software changes I think thats a better idea. One big problem though, but I think I'll let you run into it on your own.
Edit: I can't post the manual here, its too big. Boy I wish we had more posting space *hint hint*.
Give me your e-mail addya and I'll mail it to you.
__________________
All posts by Calum in this thread are copyrighted by Calum, and cannot be edited, deleted, or copied without his express permission. calum@calumsult.com
Ah, I'll add one thing. Here's the dissassembled code from a B13 rom. I think this is correct. Breaks between the different code sections are apperently noted by '02'. I've walked through some of the routines very breifly looking for some specific stuff, but really had much time to do much with it. The addressing is very wierd, if you get that figured out please post.
This is starting at rom addy 1090H (program addy 9090H), below that is all data. This is from the bin file 91nx2000.bin, hunt through the libraries I posted for it.
Edit: Fixed the starting point so the indexed addys actually come out correctly. Rom starts at 8000H, duh Calum. If you DL the text file last night grab the new one. I also made a word doc for it with page numbers, just a bit easier if you like to print stuff out like I do.
