admittedly an esoteric one but are there search terms for how the computer does all its calculations and commands and such? i mean i think i know there are various sensors and i guess there is some kind of computer code on the hard drive that tells everything what to do?
for late 80's is this "OBD II" or is there other script languages that are used in the - well is there software? or i guess it's basically a computer language loaded onto a hard drive and all the sensors send data via the wiring loom?
is there a good article or technician document on this?(!)
@Kernal
Thanks, this awesome information. I did’t know it existed, I don’t know that I would ever use it, and I didn’t know that I could search for it.
thanks man. so someone wrote code on a computer in C, compiled it (whatever that means), then loaded onto a chip in the ECU using Assembly?
and - well do you know what OBD II is or does? is it interpreting - well it's interpreting input from the sensors to the ECU?
and like how does that work? i guess all the sensors convert some kind of physical information to an electronic - or like an electrical - or how does that work exactly?
thanks man. so someone wrote code on a computer in C, compiled it (whatever that means), then loaded onto a chip in the ECU using Assembly?
and - well do you know what OBD II is or does? is it interpreting - well it's interpreting input from the sensors to the ECU?
and like how does that work? i guess all the sensors convert some kind of physical information to an electronic - or like an electrical - or how does that work exactly?
That was probably too much but IMHO it shows it's not an easy task to modify an older ECU (if possible at all). You'd probably have to hire
a software engineer who's familiar with these older ECMs/systems to have chance at it.
I think Grok is misleading you badly about the FZJ80 ECU. It's providing general background knowledge about ECU's and trying to say that it applies specifically to the FZJ80 when it doesn't have any direct information about that ECU. Why do I say this? Because the FJZ80 is completely proprietary.
The FZJ80 ECU was designed and manufactured by Fujitsu Ten Limited. It uses custom silicon for which no datasheets are available. The heart of the FZJ80 are four Fujitsu Ten integrated circuits. The part numbers of those ICs are 211923-2040, 211923-5300, 211923-6340, 211923-6690. You can search all day for information on those ICs and you won't find anything. They obviously make up some kind of CPU, but the architecture and instruction set are unknown and so are whatever algorithms Fujitsu Ten used in the implementation. I've attached a photo of the processor board from a 89661-60652 ECU, which is the updated 1997 OBD-II automatic transmission version manufactured from 03/1997 - 12/1997, so you can get an idea of the technology used in that era. As @jonheld said, it's 1990's or earlier technology. Common home computers of that time frame were things like the Commodore 64 or the Amiga, and they typically used Intel 80286 or 80386 CPUs that were implemented on a single IC. So if Fujitsu Ten was using four custom IC's instead of one, then they could have easily been using 1980's tech. At any rate, without access to internal Fujitsu Ten documentation you're never going to be able to decode the details of what's going on inside this ECU.
Common home computers of that time frame were things like the Commodore 64 or the Amiga, and they typically used Intel 80286 or 80386 CPUs that were implemented on a single IC.
"This is why AI is still bullshǐt and why human knowledge and experience is still indispensable in certain fields of technical knowledge."
Agree 100% about AI. Often when I ask Grok a complicated question it gets it wrong so have to ask it again and again, then it may get confused and stop responding. You can see by closely reading some of Grok's responses he was making a lot of assumptions and guesses.
The main purpose of posting what Grok said for anyone thinking about messing with the ECM/ECU was to give them a general idea (from what Grok dreamt) of how difficult it might be to try to reverse engineer anything that old. IME currently Grok works best as an advanced search tool that can review information from dozens of websites in seconds, but it's not yet a human brain replacement or thinking tool.
As OGBeno said, it doesn't have human experience so IME it seems to work best when the person asking the question is already
a subject matter expert (@TrickyT ) in the area of the question and can call BS and catch errors, which in this case I'm absolutely not that guy.
I do find it interesting however to watch how Grok thinks through a problem particularly if you give it a complicated math or physics question, it seems
fairly good at those.
