it is MUCH deeper then you know. The ECU that he is pluging in to is not factory. Nobody makes anything that allows you to change the values in the ECU on the fly. They do offere dataloggers and so on but they only log they can not change anything.

Other then a stand alone engin managment system I can not think of what it is.

PS how would you know what Values that needed to be set and what they effect if you don't know the program
?? I think your a bit a head of your self look in to the inner workings of the ECU and how it makes the correct changes for a given input. Start out with http://www.dsm.org
BM-

 

you'd need a eprom eraser & programmer and even with one of those you would not be able to change values on the fly. how do you think todd does his mods

 

hey I am not that stupid that I dont know that its a lot to learn..You say nothing can be changed in the ECU..well I dont agree...Cause if you use a laptop on the ECU and meassure all the readings,using the right correction programs.....then you can set another value to match the criteria you want at a certain RPM for instance.....trust me..seen it done with my own eyes*S*
Hooooooooooooooooooooooowever..*lol*...you might be right about the changed ECU though...it might not be original...

I never said this was easy guys....but I also have friends who deals with this on a daily basis and know alot more than I do..so I am just looking to see if there is any stuff made/used on DSM especially and that works fine.They will help me with all this and I thought I would help them on the way by asking if there is anything already done to these cars that I could read and take advantage of....so dont put me down like this....

Rdy2Race:

I know that he is not using anything really original and that was not the question here....was it?
And to answer your q about the value to be set...as with anoy other program...doesnt matter witch program you use...you can never know the values in advance right?? You always have to drive and log...drive and log..drive and log to be able to find out the best values for your particular car..aren't I right?

Listen guys..I am not out for a fight here..I was just asking stuff I am thinking of and trying to get some stuff in my head before starting anything on the car..I am not doing it myself as I said and I have ppl who work with this alot so..I am not worried that it will be anything wrong...
Or do you wanna argue with te guys that are helpin me...a 10.56sec Supra for instance..who does his on seetings..*hehehe*..na seriously..I know I dont know alot about this..but as I said..I am learning...ok?

)
Take care and keep boostin!!

 

not CHANGING the ECU

maybe it was worded wrong. I will tell you from a programming standpoint. You C A N N O T *modify* the program for the ECU on the fly, you simply cannot because if it is a non eprom ecu then you for sure can't ever because the program is etched in the chip and that's that. for good... no changes. If it is an eprom chip, then you have the option to place the rom into an eraser/programmer, copy the rom to a computer, modify it, delete the rom chip, then copy the modified one back to the chip, place it in the ecu and then there ya go.. that's the way todd day does it... that's the ONLY way to MODIFY the PROGRAMMING on THE CHIP ITSELF.

all those programs you're talking about... what they do is modify the signals coming INTO the ecu, not the ecu programming itself. they work much like an AFC, where you can tell it to change this signal to fool the computer. There are some things built into the ecu which will allow it to purge some solenoids or open this and open that and shut off the fuel pump and what not, but those instructions you must understand, are already built into the ecu programming, to give YOU control over it you must *invoke* those commands, which IS NOT A PIECE OF CAKE! more like a pain in the ass it involves connecting to the ecu... then finding a way to interrupt the ecu programs in order for you to make things happen, and at the same time, allow the ecu to complete it's own functions almost as if it ignores the fact you're even connected. Not an easy task

[Edited by dsm93talon on 08-13-2001 at 06:23 PM]

 

hey I bowe my head to better knowledge of course...since I said I dont know too much about this stuff..but I am learning*hehehe*..and will read all I can about this..and anyone who knows something is more than welcome to help me out to find the best way to mod my car... mail me at roger@zatzy.com

I am not a worse person than I can admit me not knowing all so...peace brothers*S*

 

I think that this will help you a lot, Read this page fwd and back and then again. your head will hurt some but it will help in understanding what is needed to be done. ( or really what is being done. for years now. )

http://www.tmo.com

give it a look you will be impressed. this is the ONLY place that I know of that REALLY does any work to the CODE it self. The JET ECU has been proven to be fake. And to be honest if you have a bunch of cash JET just has a law suit waiting on there hands as they charge and do NO work ( code from JET Vs. Code form factory, 100% same!!!! now that is a rip off!! )

Best of luck
BM

 

thats a good explanation as to why the jet doesn't work

 

Jet is a joke.So is Gforce.I've heard of something a while back called Interlink.This was a reprogrammable ECU for our cars.Can't remember the specifics on that though.
Don't you wish you had a Nissan now?
JWT rocks.

 

I have a TMO stage II EPROM. I copied the program off of the chip before I installed it(Back-up). Even having the raw data doesn't really help. Unless you know what every 3C or F2 stands for, the (assembly) code is meaningless. I suspect Todd and any one elese writing ECU code is using some type of compiler to generate the assembly code. I could be totaly wrong, since the assembly code could be modified if the programer had some type of guide or really knows their sh^t.

Where would one find information on ECU code structure?

Todd??????

 

It's really not _that_ big of a deal, at least for a good embedded systems programmer. A disassembler is all that is needed to get the asm instructions for the code (I believe that our cars use a Z80-like processor). Then it's a matter of organizing the functions (by stepping through a debugger) and breaking out the functions according to what they do. For example, some functions may look like:

fire_injector(x, y)

where x is the cylinder, y is the time duration.

So for the coders out there, the main() function would most likely look something like:

main() {

if(cold_start)
do() {
for(i = 0; i < 4; i++)
batch_fire(fire_injector(i, c))
} while(coolant_temp < 195)

...
}

etc., after which the main function would go into an infinite loop, reading sensors and performing functions, and switching from different fuel modes (open or closed), and things like that.

Of course in reality, no one needs to understand or reverse engineer ALL of the ECU code, only the small portions of practical interest (such as getting rid of fuel cut, which it turns out would be a pretty simple thing), such as TMO has done.

 

You C A N N O T *modify* the program for the ECU on the fly... ...you have the option to place the rom into an eraser/programmer, copy the rom to a computer, modify it, delete the rom chip, then copy the modified one back to the chip, place it in the ecu and then there ya go..

This is not true. I have modified the maps on a Honda ECU in real time using a laptop and some other equipment. It wasn't pretty, but it worked. I was able to change the fuel tables enough so that the car actually idled with huge cams. (Speed density systems dont like cams because it changed manifold vacuum at idle making the ECU think there is a load on the engine.)


You are correct about not being able to do anything with the mask rom chips unless you have a daughterboard to convert it to use an external rom.

-Mike

[Edited by Mike M on 08-20-2001 at 04:29 PM]

 

If you guys are talking about EPROM, it's OTP (one time programmable). Period.
You cannot erase it unless it is a EEPROM. The blank state of those devices are FFh (all ones). To program it is to blow the fuse out from 1->0 and not the other way round.

If it's a EEPROM, then the situation is different since the fuses are not blowed.

Flash memories are also reprogrammable but it's out of the topic here.

I work for a company where I write algorithms to program those chips. EPROMs, EEPROMs, uControllers, PLDs, Flashes, you name it. Our programmers support over 15,000 devices.

 

there's no reason why someone couldn't read in the EPROM binary, modify the code, then burn another EPROM. Desolder the stock EPROM/PROM from the ECU, put in a ZIF socket, crack open a 6 pack and call it a day.

 

Uhh, PROMs are one time programmable ( Programmable Read Only Memeory). EPROM *are* erasable (Erasable Programmable Read Only Memory), only erasing is done by exposing the chip to UV light for like 20 minutes. EEPROMs are Electronicaly Erasable Read Only memeory, which can be erased and reprogrammed electronicly in microseconds, without the use of UV light.

GSTSpyder, you are correct, was anyone saying otherwise?

Thats the easy part, I think theres no denying that the hard part is knowing *what* to edit in the code.

When I did that Honda, I sat im my driveway for a week straight with the car idling (my neighbors loved that..), changeing values in all the maps that I could find until I found one that affected the idle. Not very scientific, but it worked..

-Mike

 

Uhh, PROMs are one time programmable ( Programmable Read Only Memeory). EPROM *are* erasable (Erasable Programmable Read Only Memory), ....

uhhh this is not 100% correct....there are OTP-EPROMs available....these are simply normal EPROMs without the nifty little window in the chip-package to let the UV-light through....so these are only OTP (one time programmable) coz there is no way to get the UV to the die to erase the memory!

btw many embedded CPU have OTP-EPROMS...and there are also windowed versions available for developers. So you can develop on the windowed version (program, test, erase, debug, program, test, erase....) and switch to the non-windowed version for mass-production when the software is ready. This way you can cut production costs (price difference between the windowed and non-windowed version is approx. 500-1000%). The OTP-EPROMs have the advantage, that they cannot be erased by accident / over time because some dumbass removed the sticker from the window!

just my 0.02DM

 

If it doesnt have a window, and therefore not eraseable, and its not an EEPROM (electronically ereaseable), then its concidered a PROM, not an EPROM.

From dictionary.com:

EPROM (prm)
n. Computer Science
A programmable read-only memory that can be erased by exposure to ultraviolet light and then reprogrammed.
-------------------------------------------------
[e(rasable) p(rogrammable) r(ead-)o(nly) m(emory).]

PROM (prm)
n. Computer Science
Memory hardware that can be programmed only once.
-----------------------------------------
[p(rogrammable) r(ead-)o(nly) m(emory).]

The whole point of the prefix "E" is to point out that the device is eraseable. If its not eraseable, then its just a PROM.


If you look in the Digikey catalog for PIC Microcontrollers, they come as you said, in two versions, an erasable for development and a cheaper OTP for production. They are labeled EPROM and OTP. There's no such thing as a EPROM-OTP. Thats an oxymoron.

-Mike

 

If you are reffering to the actual dies inside the device, then thats a different story. But for all intents and purposes, the device is called by whats on the outside, not whats on the inside.

-Mike

 

If it doesnt have a window, and therefore not eraseable, and its not an EEPROM (electronically ereaseable), then its concidered a PROM, not an EPROM.

From dictionary.com:

EPROM (prm)
n. Computer Science
A programmable read-only memory that can be erased by exposure to ultraviolet light and then reprogrammed.
-------------------------------------------------
[e(rasable) p(rogrammable) r(ead-)o(nly) m(emory).]

PROM (prm)
n. Computer Science
Memory hardware that can be programmed only once.
-----------------------------------------
[p(rogrammable) r(ead-)o(nly) m(emory).]

The whole point of the prefix "E" is to point out that the device is eraseable. If its not eraseable, then its just a PROM.


If you look in the Digikey catalog for PIC Microcontrollers, they come as you said, in two versions, an erasable for development and a cheaper OTP for production. They are labeled EPROM and OTP. There's no such thing as a EPROM-OTP. Thats an oxymoron.

-Mike

I think there is a big misconception for what EPROM, PROM and OTP means....OK another try

there is one big difference between a PROM (a real PROM) and an EPROM, its the way the data is stored physically!
1.) The PROM-type blows fuses/small diodes in an array (to store data), thus it is irreversable!!
2.) The data storage in an EPROM-type is reversable (don't have the details right now but I can ask a co-worker if you're interested)!!!
If you have an EPROM-type memory without a window it still remains an EPROM-type memory (the die doesn't change when its in a sealed package ), but it is called OTP...because there is no way to get the UV to the die!(Except you drill the package)

 

PROM
prom
n. high school
- a dance at the end of the year, usually held by the junior class

EPROM
electronic prom
n. high school
- a program you load on your computer where you can pretend you are at your high school prom, where you can dance and get it on with any girl in your class with the click of your mouse

 

All this info is great. For development I prefer flash memory. It's really an EEPROM that can be programmed onboard via a small flash program. I would love it if the DSM had this option. This would truly make it programmable on the fly.

I would have to say that even though the EPROM die structure is the same with or with out the window, it really should be called a PROM if the chip can't be erased. It just makes more sense that way. I sure there are companies that call their non-windowed EPROMS, EPROM-OTPs. That probably made sense to someone also.

My DSM used a 27c256AK. This chip is erasable via UV light. Either way a would still grab a fresh chip. I have experienced problems with EPROMS that have been erased several times. So I don't use them for the final burn.

To burn, or not to burn that is the question.

Lets burn.....................

 

man.. you guys are so funny
Ok.. i got it mixed up.
EPROM - Eraseable Programmable READ ONLY MEM. It is either OTP or UV eraseable depending on the package type. If it does not have a window, it's OTP (although you can still cut a window by force )
E2PROM - Electrical Eraseable PROM
On the other hand PROM is just where fuses get blown.
Technically, OTP is not *really* One time programmable because you can still program from 1->0 but not the other way round.
If you have program AEh (1010 1110) to an address, it still can be program to 8Ah (1000 1010) and not A9h (1010 1001).
so going from 1->0 is ok but not the other way round.
However, this does not apply to all PLDs since there is a lot of complexity.

It terms of applications, flash is cheaper. However, they cannot be reprogrammed unless it's erased. They can either be chip erased or block erased. That's where it is slower (depending on the mem size) if you have to erase before programming.

EEPROM on the other hand does not need to be erased before program (the erase is done in the chip internally and the user is not aware of it).


[Edited by jw on 08-28-2001 at 04:18 PM]

 

This device is supported with our programmers . I dont even know it since I dont have the EPROM version of ECU for my DSM.

My DSM used a 27c256AK. This chip is erasable via UV light. Either way a would still grab a fresh chip. I have experienced problems with EPROMS that have been erased several times. So I don't use them for the final burn.

To burn, or not to burn that is the question.

Lets burn.....................

 

Yes JW. You are correct. I use flash ROM so often I forgot that I erase each block before it's written to. I've also don't some Atmel PLD/PLA programing. It used a totaly different burner & program. I kinda figured it was special. Same with TI 320TMS chips. Isn't electronic fun.....

No EPROM ECU?????
Poor guy.....