how does this work?

[AllanL]

i got this ecu from a friend's early evo (evoI).
there's a switch wired to three pins on the rom.
one foot of the pin is lifted from the socket and is the common wire on the switch.
i believe this is a 2-map rom, but i couldn't read the japanese instruction on the ecu housing, so i couldn't tell as yet.
hoping for anyone's advice on how to read the contents of the rom. can i just pop the rom and read using tunerpro?
thank you.

http://i269.photobucket.com/albums/jj70/allanlavarias/n65-0129.jpg

http://i269.photobucket.com/albums/jj70/allanlavarias/n65-0130.jpg

http://i269.photobucket.com/albums/jj70/allanlavarias/n65-0131.jpg

http://i269.photobucket.com/albums/jj70/allanlavarias/n65-0133.jpg

[AndyF]

Looks identical to a chip that I had fitted to mine originally Allan. The switch is actually for switchable ROM images not just switchable maps.

The only way to read it AFAIK is to use an Eprom reader. That's how I read mine

Andy

[bes]

I also have similar device take out from my friend ecu lancer gsr. Its also used three wires but its was connected to the eprom base come with IC 74HCxxxxx. I also believed it has 2 rom inside that eprom. The way I read the bin is by using eprom reader and use offset address 0000-7fff for first bin and 8000-ffff for the second bin. So you then will get 2 separate 32k bin rom images. Unfortunately I cannot access to read the rom image using evo xdf....maybe it use totally rewriten code.

[AllanL]

EPROM reader like Burn2 with Tunerpro?
Thanks.

[bes]

Yes....Im using burn2 and tunerpro

[AllanL]

I see. So if I read this, I'd see the entire hex file filled with 'strange' alphanumeric values?
Thanks.

[AndyF]

Allan,
Yes you will get the read image in hex.

I used a Willem Eprom programmer that I got from ebay for about £20 IIRC.

Mine also was completely re-written specifically for the chip and so didn't contain much of the standard code I seem to recall although I might have a look back through it now I know about the disassembly a lot more than I did a few years ago.

Andy

[AllanL]

Thanks Andy.

By any chance would you have the .xdf for this two image ROM, or did you completely scrap it out for your own images?

With a single image ROM and no switches, would I still be able to use the ECU?

[bes]

Allan...
If you use 512kb chip the ecu will read the upper bin image without switches,
For single image rom I have no idea as I never try it before.

[AndyF]

Allan,
I just scrapped the image for my Ostrich and so didn't even bother looking at the code.

The code is written differently to the std ECU rom as well so I didn't even get as far as doing any disassembly on it.

Sorry

Andy

[merlin]

I loved (not) how a screened pair wire was used, and the address line connected to the screen, not the ground/0V line. Silly.

[AllanL]

Allan,
I just scrapped the image for my Ostrich and so didn't even bother looking at the code.

The code is written differently to the std ECU rom as well so I didn't even get as far as doing any disassembly on it.

Sorry

Andy

I see, but can I still use the ECU as it is, and just the replace the ROM with a single image one? I'm afraid I might mess up something if if use it as it is, without the switched ROM. :confused1:

[AndyF]

I would have thought you would be OK to just pop the ROM out, install the Ostrich and go as normal.

The actual working of the switch etc. is done internal to the ECU coding and nothing else is changed on the actual ECU board.

The ECU in mine is the same one that had the twin map setup as that one originally and runs perfectly well.

Andy

[AllanL]

I understand. I was just afraid of what was soldered underneath the ROM, and covered with all of the glue.
Thanks Andy.