My 98 GST 5psd ECU just arrived
it's a MD346675
and the board says JE331B156C
Then yes, it is flashable
In that case it seems there is zero difference between AWD and FWD ECUs. The board numbers match, the difference must be in software. Can you post FWD ROM so that we can compare it with AWD ROM.
I think Ceddy has the same board, but in AWD ECU.
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That's the MD number, but the plastic circuit board (PCB) numbers are the same, so I guess MD number changes only because there is different ROM image inside ECU, not because of different hardware.
If this is true that would mean we can buy whichever ECU we want (AWD/FWD) and just flash it to needed ROM.
The only question is if JE331B156D ROM can be written to JE331B156C board. That would be very interesting, because we already have a latest ROM of JE331B156D board posted in one thread.
What's going to be different between fwd and awd ROMs though? Speed limiter on fwd ROMs, but that should be scaleable, no? I don't know if this is applicable to the 98/99 boards, but I came across this: Warning!!! This Mod Is Extremely Dangerous!!!
First I tried Quad Speed Logging 62500 vs 15625 baud. I only noticed a 15% increase in speed, not the 400% you would expect.
The OP 2.0 doesn't log super fast because of its pass-thru design. I'm going to try my cheapo ebay cable at 62500 baud to see if I get better results, I think the OP 2.0 cable is the bottleneck.
I tried the set 5 degrees, for base timing, works perfect.
Trying to pull DTCs failed. Got OpenPort not responding error.
Run Open Loop Always, is very nice, makes scaling your MAF and Injectors very easy.
Tomorrow, I'll try to some Logging Speed Comparisons between the OP 2.0 and the ebay VAG 409.1 cable.
Open loop will hurt your gas mileage and your emissions (if you care). It is useful for tuning purposes and if your car is extremely consistent and you can tune you could increase your fuel efficiency by moving from a 14.7 target to 15.3 using the fuel map but much nicer would be if someone could write a patch that allowed the closed loop system to be controlled by a wideband and then set to a user selectable (or just 15.3) crossover point.
For advancd stuff we need the [ECU pin <-> CPU pin] diagram. Does anyone have a fried ECU for sale?!!!
Quote:
Originally Posted by Ceddy
First I tried Quad Speed Logging 62500 vs 15625 baud. I only noticed a 15% increase in speed, not the 400% you would expect.
IIRC, h8/539F spec mentioned something about speed synchronization. That is, if flash speed was faster or slower than something CPU would adjust to needed speed anyways.
I need to re-read the spec again, but there was some sync stuff inside.
First I tried Quad Speed Logging 62500 vs 15625 baud. I only noticed a 15% increase in speed, not the 400% you would expect.
Are you doing this with plain old MUT (with an increased bitrate), or did you rework the protocol a bit to accommodate? Over on the Evo side of the house, we discovered pretty quickly that increasing the bitrate only served to get us to the maximum rate that the serial interrupts and MUT requests could be processed, which ended up being a pretty disappointing speed (an improvement, but nothing to write home about).
Going off on a tangent: IMHO, better would be a different protocol than MUT altogether; jcsbanks went down that road with his DMA implementation on the SH ECUs. While I don't believe H8 supports DMA, the idea is basically sound: instead of a request->reply cycle for each value you're interested in like MUT does, transfer blocks of memory either directly (ie. give me 0xFF bytes starting from 0xEE80) or via a table of indirect references (like the MUT table). Using DMA was nice, since you could force the ECU to disable interrupt handling while a block was transferring, but surely you could cook up something on this processor.
Part of that was live RAM updating as well, which is fantastic if you have the memory (which, sadly, H8s seem to be pretty weak on), since you could just move fuel, timing, and other "interesting" maps to RAM. Even the MUT table, which turned out to be a pretty cool side-effect.
If you're at all curious, check the EcuFlash forum on EvoM; there's a thread by jcsbanks titled "How the DMA code works" or something to that effect. I replied in there with a rudimentary "spec" for it's behavior, and the custom MUT commands that it uses as triggers. (It's actually rather nice in that respect: you can test for the existence of the mod, and use it if it's there, or go back to MUT if it isn't.)
Good job on getting it to work.
I have to agree with the earlier statement of about time though.
I've been doing this with GM ECM's for over a decade.
Really there's no reason the 96-97 ECU's can't do the same thing.
any obII computer in any car from any manufacturer is capable of doing this if someone actually makes the program to do it.
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92 AWD 2.3L 6/5/4 353AWHP@25psi on a mustang dyno
Really there's no reason the 96-97 ECU's can't do the same thing.
any obII computer in any car from any manufacturer is capable of doing this if someone actually makes the program to do it.
Sorry, the earlier 2G ECUs hardware doesn't support Electrically Erasable ROM for changing the software. Only the 95's with EPROM support and the 98/99 ECUs with Flash ROM in the CPU.
the obdI ECM in my camaro didn't either and no one thought it could be done 10 years ago and at the time the only thing to do was take the prom out and flash it.
Then moates and other people came along and plugged in flash chips you can read/write on the fly while driving.
It's 10x harder to bring an obd1 ECM up to this kind of tech, then it is an OBDII.
Again with the 97-98 I say hasn't been done yet but it's not impossible...
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92 AWD 2.3L 6/5/4 353AWHP@25psi on a mustang dyno
You don't need the full adapter set, if you look on the site you can see that two of the adapters are for Subarus. Pick up the cable and the Mitsu adapter, though I'm not sure if the Mitsu adapter is really needed or not.
As to the other question, have you looked through ECUFlash's site and the forum section on Evolutionm?
And how is the procedure of reading/flashing the ECU ???
all you should need is the openport 2.0 adapter and the Mitsubishi flash adapter, unless you feel the need to flash a subaru or two. just be careful you could go to jail for indecent exposure ..
flashing with ecu flash is easy plug in the op2.0 and turn the ignition on. click on the icon with the blue arrow first to read the ecu. after your done you can turn the ignition off. always save a copy of your stock rom just in case... close that rom in ecu flash and open your modified rom. plug in the flash connector from the op2.0 adapter to the flash plug next to your OBD2 port, turn the ignition on and click on the icon with the red arrow, that will write the new rom to the ecu..... turn ignition off.... easy stuff. takes anywhere from 45 seconds to 2 minutes on an evo ecu depending on how much is modified..
OK, I have a question. The flash adapter, how many wires are in it, and where do they go. I know since I have a 95 I need to pin a wire to the ECU, I foget the pin location but have it in my notes. Is that all that's in the flash adapter? Is the openport cable able to flash without the adapter, by that I mean; is there already a flash lead in the openport connector and the reason we need to use the adapter is because the DSM has a seperate connector for flashing?
I'm asking because I'd rather just pin the wire into the OBDII port instead of trying to track down a flashport. I hope that sounded coherant, I'm really tired right now.
OK, I have a question. The flash adapter, how many wires are in it, and where do they go. I know since I have a 95 I need to pin a wire to the ECU, I foget the pin location but have it in my notes. Is that all that's in the flash adapter? Is the openport cable able to flash without the adapter, by that I mean; is there already a flash lead in the openport connector and the reason we need to use the adapter is because the DSM has a seperate connector for flashing?
I'm asking because I'd rather just pin the wire into the OBDII port instead of trying to track down a flashport. I hope that sounded coherant, I'm really tired right now.
Yes FlashPort is just one wire. You will need to add a pin to your ecu harness at pin 79.
I added a wire with a 2.5mm audio plug. It plugs right in to the OP 2.0.
Thanks, that's what I thought. Should be getting my stuff next week, so I'm trying to plan things out a bit.
So, on the Tactrix adapter is the 2.5mm port the only flash output, or is there also a pin in the OBDII part? I'd like to wire the flashport into the OBDII connector on the car is what I'm getting at.
AFAIK 98-99 turbo cars and all 2g NT cars (4g64 spyders not included I have no idea what they have). The NT cars are only useful for stealing the harness. At this point I'm just stuffing a wire from that pin into the connector on my cable.
The 98-99 NT 4g64 spyder ecu has a black case just like the 98-99 GST/GSX ecu. I don't know what chip or processor it has though, I do have my original NT 4g64 99' ecu that i used before I switched to the 99 GSX ecu before I switched to a 95' eprom .
I'll take the case off the 99 NT spyder ecu and compare it to my 99 GSX ecu next time I'm home. I do recall that the md number is a digit off of the GSX ecu MD359405 i believe.
I know the NT spyder ecu does not have a resistor for the knock sensor circuit (from what I remember of the case off) so most likely it wouldn't be a good swap option. Probably still flashable though...
Quote:
Originally Posted by the_mork
AFAIK 98-99 turbo cars and all 2g NT cars (4g64 spyders not included I have no idea what they have). The NT cars are only useful for stealing the harness. At this point I'm just stuffing a wire from that pin into the connector on my cable.
