barks944

Looks like thats a bit out of my League. You must be pretty good at this kind of thing to make sense of it.

phil823

i was good...and as the go a lose alittle insight every time!....

rouge does the computer stuff lol......i just give GREAT moral support!

Rogue_Ant

It has been a bit of a learning curve, as my assembly experience was pretty limited before I started on the 951...

barks944

Maybe I will keep at it then. Do you have a proper IDA pro license? I've been opening it as a binary file in the free non commercial version. Keeps asking for the entry point, does it start at the first byte?

Rogue_Ant

First byte, yes. There are also the interrupt vectors as well.
IE0 = 0x0003h
TF0 = 0x000Bh
IE1 = 0x0013h
TF1 = 0x001Bh
Serial = 0x0023h


-Rogue

peanut

I read an article somewhere recently showing the method for converting the early 8 valve ECU chip holder to 28 pins to take a late type EPROM ? presumably this would allow early cars to modded ?
http://www.the944.com/

Rogue_Ant

Ok, you guys are talking about this:

BMW board conversion

Although this does convert to an EPROM model, it is still an older version of the Motronic, and will not work with this current bundle.
If there is enough interest, I'll put together something for the early guys, who have done the BMW board conversion. I do wonder if there are many out there, and if it is worth the time...?

barks944

So in 1988 the DME was changed a little. It seems a 28-pin socket was installed on the mainboard and the 4Kx8 EPROM was changed for an 8Kx8 EPROM. Is the EPROM on the 8051 chip or is it a separate chip?

peanut

actually I was referring to the 86 to 88 DME conversion on this site
http://www.the944.com/

is it the same thing?

barks944

They achive the same thing. Rogue_Ant's link descirbes a method using part of a 28pin BMW DME whereas your link involves modification of the 944's DME to make it 28 pin. Either way you end up with a 28pin EPROM socket in your DME .

Edit: Saying that there may be other differences in the boards function. I.e a BMW 28-pin board may be slightly different in function to the modified 24-pin 944 board.

barks944

Ant, I don't quite understand the difference between the 28 adn 24 pin chips. Is the total code size for the DME 4KB or 8KB. It seems like the file you listed here is 4KB which means it would fit in the EPROM of both the 24 and 28pin chips.

phil823

if im correct it would be MUCH easier to swap a an 85-87 8v NA DME and AFM. this would give you better drivability and the upgraded DME Board

peanut

as I understand it there is no difference between the boards in terms of performance.

The 88 ECU had a 28 pin socket fitted to allow for a later 28 pin EPROM to be used which has built in memory. A link wire was also added to the 88 board to instruct the board to ignore the on-board memory and use the chip memory.

other than that nada

Looks like you can use a pre88 ECU EPROM on a post 88 car and a post 88 ECU EPROM on a pre 88 car simply by switching chips and adding/removing the on board memory link

markl951

I'm interested

I've done a number of early DME (fixed ROM to socketed EPROM) conversions using FR Wilk's adapter boards as well as the BMW board swap. I've run across a few early DMEs that have a socketed 2732 EPROM instead of fixed ROMs but they are not as common. They all have the same DME part number so you have to open them up to find out.

phil823

i was told awhile ago it has no performance gains, but something about how the coding was ran and the newer AFM gave a better drivability