944 DME Project

[barks944]

The original processor ran at 8MHZ I think but architechturally microprocessors have moved on a lot so this may not indicate the true performance benefit of this processor over the original.

In terms of memory, the chip itself has 128KB self-programming Flash Program Memory, and a 4KB EEPROM. This is supplimented by an external 1024KB EEPROM. This may change to an SD slot for hours and hours of datalogging joy . The original system has 64K of EPROM.

 

[GPF]

Hi Tom,

Sounding great!

Where will all the maps be held and how will the user access them for tuning? I presume the existing 24/28pin chips will not feature??

 

[barks944]

The Maps will be stored in EEPROM on the new board, this is re-writeable by the microprocessor and can be re-written a huge number of times. The tuning program will probably be for windows based laptops inititally. The laptop can connect to the DME via usb or bluetooth or pretty much any form of modern communication bus. I could even do something like connect a 3G phone to the DME via bluetooth and use the internet connection on the phone to transmit the data to and from any internet connected laptop in the world. In short the options for communications are great. Once the laptop is connected to the DME the maps can be updated by sending data to the microprocessor which will update the maps in the EEPROM. This can probably be done seemlessly while the engine is running.

I hope to write some interesting tuning software, I want to make it a little differently to the common approach of having an excel type spreadsheet. I want to make it a 3D moveable draggable map. So rather than plugging numbers into a cell on a spreadsheet you are just clicking on a point on a 3D map and pulling it up or down or maybe holding left mouse will raise it slowly and right mouse will lower it so you can sort of paint over the map. I also want to make it show the currentl load point in real time with a trail to show where on the map the engine has been operating and indicate any points where knock is detected. Obviously you might want to adust AFR and ignition for any specific load site so I think I will make it so you have a button to quickly toggle between ignition and AFR. I hope it will be the sort of thing you can use from the passenger seat very effectively.

 

[GPF]

Presumably you will be able to extract the maps for quiet analysis "offline" and then rewrite them with adjustments made, or replace them with maps obtained/shared from someone - just like plugging an aftermarket/own custom chip in?

Re the tuning software, I'm using TunerProRT at the moment to make my own .bin files and burn to chips. It already has the 3d map functionality that you are thinking of and, with an interface to the ecu, can datalog, show data in real time, allows you to make dashboard guages etc. I presume you want to write some tuning software for your own interest, but if not TunerProRT is well worth a look.

 

[barks944]

Yes you will be able to extract the maps, I was thinking of making a website to share maps with other users. Sort of a collaborative tuning effort where you could group cars by engine spec and the people in the groups could share tuning experiences.

There is the possibility to use some pre-made tuning software like tunerproRT, not sure I would be able to interface it with my ECU very easily though. A guy who makes tuning software for Saabs has offered to help with making the software.

I take it you need the emulator device for the connection to the DME and all the datalogging features?

 

[GPF]

ORIGINAL: barks944
I take it you need the emulator device for the connection to the DME and all the datalogging features?

I just use a chip burner at present - so no real time tuning. I just datalog, review, alter the relavant map, burn new chip, repeat....

I may get one just to speed the process up but I don't think that the datalogging and dashboard work with it (something peculiar to our DME I think?) - which is why I've not bothered so far.

 

[barks944]

There are two injection outputs on the 944's DME but for some reason they are paired up onto a single driver on the 944. Would there be any benefit to driving injectors in pairs? You are still stuck injecting half your fuel into a closed port.

Edit: Well I suppose its better than 3/4...

 

[944 man]

Hello. I havent commented on this thread so far; although I have been watching with interest. Will limited OBD2 functionality be a possibility?

 

[barks944]

From what I have read ODB is just a common protocol for identifying faults on an engine. I was planning to implement my own system which would simply tell the end user in plain text what faults have occurred. Are you interested from the perspective of being able to diagnose faults or would you like the OBD2 protocol to be implemented for other reasons?

 

[944 man]

Other reasons. There are a number of commercial products available which offer a graphical interpretation of the OBD2 values. I use 'Centrafuse' on a car PC and this is one of its features.

 

[barks944]

Interesting, I have seen a few products that use OBD2 like this. There are other benefits I guess, like the average garage can interrogate the DME when fault finding. What kind of values can you get over OBD2, RPM, AFR etc?? I'll be looking into this as it sounds like a good idea. I hope I can write something that supports OBD2 but with extra features (if necessary)...

 

[barks944]

ORIGINAL: GPF

ORIGINAL: barks944
I take it you need the emulator device for the connection to the DME and all the datalogging features?

I just use a chip burner at present - so no real time tuning. I just datalog, review, alter the relavant map, burn new chip, repeat....

I may get one just to speed the process up but I don't think that the datalogging and dashboard work with it (something peculiar to our DME I think?) - which is why I've not bothered so far.

Just made the association with rogue tuning. Ant is a top bloke and I have been chatting with him on reutterwerk about this project.

 

[GPF]

ORIGINAL: barks944
Just made the association with rogue tuning. Ant is a top bloke and I have been chatting with him on reutterwerk about this project.

Yes he's great, I've been exchanging emails and files with him for a while. He's been very helpful with regard to adding extra items to create a custom .xdf file (defines the tables in the .bin) so I can easily change things that are not in his standard definition, and explaining how some of these other tables are used.

 

[barks944]

I have FRWILK's DME editor, this has access to all the maps in the Motronic DME. I will be using this to make the base maps and all the cold start values etc. for this system. What Chips/Burner do you use btw?

 

[barks944]

Having done some more reading I think implementing OBD2 is an excellent Idea. I can support many standard codes to allow anyone with an OBD2 reader to get diagnostics and sensor information from the car and then with my software additional tuning features will be available. This will also allow custom dataloggers and displays that work on the OBD2 port to work on the 944 which is great. Thanks for the suggestion 944 man!

 

[GPF]

ORIGINAL: barks944

I have FRWILK's DME editor, this has access to all the maps in the Motronic DME. I will be using this to make the base maps and all the cold start values etc. for this system. What Chips/Burner do you use btw?

I have a TOP853 burner and use AT28C64B's.

So do you have a full directory of the .bin file? []

 

[barks944]

I've got binaries for a number of cars, 944 lux, turbo, S2 and 968 I think.

 

[GPF]

ORIGINAL: barks944

I've got binaries for a number of cars, 944 lux, turbo, S2 and 968 I think.

But do you have a full listing of the maps, their purpose and their locations? (I'd quite like to fill in the gaps in my definition file for TunerPro and identify any free space to add some tables.....)

 

[colin944]

You should go onto rennlist and find a guy called "rouge ant" he has done alot of work on tunning 944's and bosch motronic systems.He put a bundle onto the site that lets you change maps.

 

[barks944]

Thanks, I've already had some dealings with Ant though! He's a great chap and has done some really good work on the 944's.