The Subaru SVX World Network   SVX Network Forums
Live Chat!
SVX or Subaru Links
Old Lockers
Photo Post
How-To Documents
Message Archive
SVX Shop Search
IRC users:

Go Back   The Subaru SVX World Network > SVX Main Forums > Technical Q & A

Reply
 
Thread Tools Display Modes
  #1021  
Old 02-20-2010, 09:41 AM
b3lha's Avatar
b3lha b3lha is offline
Phil & Belha
 
Join Date: Aug 2001
Location: Alcyone Limited, Buckinghamshire UK
Posts: 2,671
Re: Memory dump of ECU

Here's something interesting: An open source SSM software with versiosn for windows and linux. It seems to be for early OBD2 Subarus. They say Legacy/Liberty, Outback, Baja, Impreza, Forester and Tribeca (not before MY1999). But it must be worth trying it with a 97 SVX.

The screenshots show it can read an OBD1 TCU. So we might even be able to do something with it on the OBD1 cars.

http://developer.berlios.de/projects/freessm/
__________________
Subaru ECU and TCU Website
1992 Alcyone SVX Version L
1992 Alcyone SVX Version L
1994 Alcyone SVX S40-II
2004 Subaru Legacy 2.5 SE Sports Tourer
1996 Subaru Legacy 2.2 GX Wagon
1988 Subaru Justy J12 SL-II
Reply With Quote
  #1022  
Old 04-04-2010, 05:35 AM
b3lha's Avatar
b3lha b3lha is offline
Phil & Belha
 
Join Date: Aug 2001
Location: Alcyone Limited, Buckinghamshire UK
Posts: 2,671
Re: Memory dump of ECU

I've been talking to Frank, the FreeSSM developer, and he told me about an older version of the SSM protocol. He calls it SSM version 0 (because ours is version 1). The difference is that SSM0 is clocked/synchronous while SSM1 is asynchronous. SSM0 was used on the 3rd Gen Subaru L-Series.

In an asynchronous system, the Select Monitor and the ECU each have a clock. The two clocks run at the same speed (baud rate). Every tick of the clocks, the SSM writes 1 bit of data onto the wire and the ECU reads it.

But on a clocked/synchronous system, there is only one clock, in the Select Monitor. The clock signal is shared between the Select Monitor and the ECU via an extra wire. The Select Monitor writes a bit of data onto the wire and then sends a pulse down the clock wire to tell the ECU to read it.

Anyway, from looking at the 92 select monitor ROM that LAN sent me, I think our Cruise Control Unit uses SSM0 at 250 baud. That's why I haven't been able to talk to it, and why there is an extra wire in pin 4 of the diagnostic plug. When you select "Cruise Control Unit" on the SSM, it switches to synchronous mode, when you exit, it reverts back to asynchronous mode.

With our current interface design and software, there is no way to support SSM0. So there is no way to talk to the cruise control unit. Unless maybe later SVXes had SSM1 cruise control. Anybody know if the cruise control part number changed at any point during production? Maybe the OBD2 cars had an SSM1 CCU?

While it's possible to redesign the interface and software, I'm not sure it's worth the effort. The CCU is probably even dumber than the A/C unit. So I'm going to admit defeat on talking to it for the time being.
__________________
Subaru ECU and TCU Website
1992 Alcyone SVX Version L
1992 Alcyone SVX Version L
1994 Alcyone SVX S40-II
2004 Subaru Legacy 2.5 SE Sports Tourer
1996 Subaru Legacy 2.2 GX Wagon
1988 Subaru Justy J12 SL-II

Last edited by b3lha; 04-04-2010 at 05:07 PM.
Reply With Quote
  #1023  
Old 04-04-2010, 05:41 AM
b3lha's Avatar
b3lha b3lha is offline
Phil & Belha
 
Join Date: Aug 2001
Location: Alcyone Limited, Buckinghamshire UK
Posts: 2,671
Re: Memory dump of ECU

While I'm on the subject, here's a screenshot of a special prototype version of FreeSSM with OBD1 SVX support. There is still a lot of work to do, but the basics are there. I've offered to help Frank with getting the OBD1 stuff finished and working. It will support not just the ECU, but also the TCU and maybe A/C and 4WS units. OBD2 should work already.

Attached Images
File Type: png Screenshot1.png (118.0 KB, 1781 views)
__________________
Subaru ECU and TCU Website
1992 Alcyone SVX Version L
1992 Alcyone SVX Version L
1994 Alcyone SVX S40-II
2004 Subaru Legacy 2.5 SE Sports Tourer
1996 Subaru Legacy 2.2 GX Wagon
1988 Subaru Justy J12 SL-II

Last edited by b3lha; 04-04-2010 at 05:44 AM.
Reply With Quote
  #1024  
Old 04-04-2010, 01:21 PM
NeedForSpeed NeedForSpeed is offline
Registered User
 
Join Date: Apr 2004
Location: SoCal / Texas
Posts: 1,738
Registered SVX
Re: Memory dump of ECU

Hi Phil,
The FreeSSM looks fascinating, good luck on continued refinement. It would be fascinating to watch the systems in motion .

Question,
Is there a pracitical purpose in wanting to talk to the cruise control unit, other than the challenge and the fact that this system remains a mystery?
__________________
Special Thanks to Our Friends and Sponsors:
*
http://www.alcyone.org.uk/ssm http://www.PhenixWheels.com http://www.dba.com.au/
http://www.ClassicSoftTrim.com http://ToyoTires.com/tire/pattern/versado-lx Gillman Subaru of Houston
"QuickChange" http://www.TransGo.com/ http://www.PlanetSVX.com Bontrager Works,

'92 Subaru SVX LS-L Claret ORIGINAL OWNER
'92 LS-L Pearl~ '92 LS Pearl~ '92 LS-L Teal~ '92 LS-L Silver~ '95 LSi Polo~
'92 JDM Alcyone SVX Version-L 4WS Pearl~ http://www.subaru-svx.net/forum/showthread.php?t=54143
'92 JDM Alcyone SVX Version-L 4WS Ebony~ http://www.subaru-svx.net/forum/showthread.php?t=54117
Reply With Quote
  #1025  
Old 04-04-2010, 01:44 PM
b3lha's Avatar
b3lha b3lha is offline
Phil & Belha
 
Join Date: Aug 2001
Location: Alcyone Limited, Buckinghamshire UK
Posts: 2,671
Re: Memory dump of ECU

Quote:
Originally Posted by NeedForSpeed View Post
Question,
Is there a pracitical purpose in wanting to talk to the cruise control unit, other than the challenge and the fact that this system remains a mystery?
Mainly just curiousity.

I had an idea in the back of my mind that maybe I could make the car speed up and slow down from the laptop by writing to the cruise control speed memory location. If it was possible, that could open the door to some interesting mods.

Including the "turn your SVX into a Toyota" mod.
__________________
Subaru ECU and TCU Website
1992 Alcyone SVX Version L
1992 Alcyone SVX Version L
1994 Alcyone SVX S40-II
2004 Subaru Legacy 2.5 SE Sports Tourer
1996 Subaru Legacy 2.2 GX Wagon
1988 Subaru Justy J12 SL-II
Reply With Quote
  #1026  
Old 04-12-2010, 04:35 PM
b3lha's Avatar
b3lha b3lha is offline
Phil & Belha
 
Join Date: Aug 2001
Location: Alcyone Limited, Buckinghamshire UK
Posts: 2,671
Re: Memory dump of ECU

I've just put an updated version of my linux software on my website.

There was a weird issue with recent versions of linux where the software would just hang. I found a few other bugs while searching for it.

So grab the latest version if you want to download your ECU or TCU. Sorry I still don't have a windows version available.
__________________
Subaru ECU and TCU Website
1992 Alcyone SVX Version L
1992 Alcyone SVX Version L
1994 Alcyone SVX S40-II
2004 Subaru Legacy 2.5 SE Sports Tourer
1996 Subaru Legacy 2.2 GX Wagon
1988 Subaru Justy J12 SL-II
Reply With Quote
  #1027  
Old 05-10-2010, 04:55 AM
Dessertrunner's Avatar
Dessertrunner Dessertrunner is offline
Registered User
 
Join Date: Jul 2005
Location: Griffith NSW
Posts: 2,156
Re: Memory dump of ECU

I have complied a numer of sample select montor reads of the screen into a excel sheet. Here it is.
Tony
Attached Images
File Type: jpg Summary report on select monitor copy.jpg (256.5 KB, 564 views)
__________________
1995 - SVX 700,000 K Mine, DMS Struts to lift car 2in. Tyres Wrangler Silent Armor 235/70R16, PBR Radiator. 6 speed with DCCD and R180 rer diff, Heavy duty top strut mounts front and rear. Speedo correction box fitted. New stero (gave up on the old one). Back seat removed and 2 spare tyres fitted for desert driving. ECUTune SC sitting in the box for the next SVX.
1992 - SVX 255 K Wife (Want to stay Married so not allowed to fit SC)
1992 - SVX Pearl with black roof race car roll cauge etc ready to race. Ex Tasman Targa car.
1995 - SVX Green low k mint condiation.
1995 - SVX Rally car, ex Matts car. Now to be used on track.
1992 - SVX red & Black being converted to Mid Engine.
1995 - SVX Red 143,000 bit rough.
Owned 5 others Subaru back to a 1974 1400 GSR.
Reply With Quote
  #1028  
Old 05-10-2010, 03:29 PM
NeedForSpeed NeedForSpeed is offline
Registered User
 
Join Date: Apr 2004
Location: SoCal / Texas
Posts: 1,738
Registered SVX
Re: Memory dump of ECU

Quote:
Originally Posted by Dessertrunner View Post
I have complied a numer of sample select montor reads of the screen into a excel sheet. Here it is.
Tony
Tony, nice work, Phil will have fun with that.
I know this is way down on the priority list, with all the projects you have going on, but Phil also needs a TCU download of the TCU in your S3 front clip for his data base. Is that possible?
Ron
__________________
Special Thanks to Our Friends and Sponsors:
*
http://www.alcyone.org.uk/ssm http://www.PhenixWheels.com http://www.dba.com.au/
http://www.ClassicSoftTrim.com http://ToyoTires.com/tire/pattern/versado-lx Gillman Subaru of Houston
"QuickChange" http://www.TransGo.com/ http://www.PlanetSVX.com Bontrager Works,

'92 Subaru SVX LS-L Claret ORIGINAL OWNER
'92 LS-L Pearl~ '92 LS Pearl~ '92 LS-L Teal~ '92 LS-L Silver~ '95 LSi Polo~
'92 JDM Alcyone SVX Version-L 4WS Pearl~ http://www.subaru-svx.net/forum/showthread.php?t=54143
'92 JDM Alcyone SVX Version-L 4WS Ebony~ http://www.subaru-svx.net/forum/showthread.php?t=54117
Reply With Quote
  #1029  
Old 05-10-2010, 03:43 PM
Dessertrunner's Avatar
Dessertrunner Dessertrunner is offline
Registered User
 
Join Date: Jul 2005
Location: Griffith NSW
Posts: 2,156
Re: Memory dump of ECU

Hi Ron,
Yes, Do you know if he also needs the Oz ECU. I might have one of them to send.
This morning I did a cold start readings as well.
Tony
__________________
1995 - SVX 700,000 K Mine, DMS Struts to lift car 2in. Tyres Wrangler Silent Armor 235/70R16, PBR Radiator. 6 speed with DCCD and R180 rer diff, Heavy duty top strut mounts front and rear. Speedo correction box fitted. New stero (gave up on the old one). Back seat removed and 2 spare tyres fitted for desert driving. ECUTune SC sitting in the box for the next SVX.
1992 - SVX 255 K Wife (Want to stay Married so not allowed to fit SC)
1992 - SVX Pearl with black roof race car roll cauge etc ready to race. Ex Tasman Targa car.
1995 - SVX Green low k mint condiation.
1995 - SVX Rally car, ex Matts car. Now to be used on track.
1992 - SVX red & Black being converted to Mid Engine.
1995 - SVX Red 143,000 bit rough.
Owned 5 others Subaru back to a 1974 1400 GSR.
Reply With Quote
  #1030  
Old 05-10-2010, 03:49 PM
NeedForSpeed NeedForSpeed is offline
Registered User
 
Join Date: Apr 2004
Location: SoCal / Texas
Posts: 1,738
Registered SVX
Re: Memory dump of ECU

Quote:
Originally Posted by Dessertrunner View Post
Hi Ron,
Yes, Do you know if he also needs the Oz ECU. I might have one of them to send.
This morning I did a cold start readings as well.
Tony
Hi Tony,
I don't know if he needs that, I'm sure he will post here and let you know,
__________________
Special Thanks to Our Friends and Sponsors:
*
http://www.alcyone.org.uk/ssm http://www.PhenixWheels.com http://www.dba.com.au/
http://www.ClassicSoftTrim.com http://ToyoTires.com/tire/pattern/versado-lx Gillman Subaru of Houston
"QuickChange" http://www.TransGo.com/ http://www.PlanetSVX.com Bontrager Works,

'92 Subaru SVX LS-L Claret ORIGINAL OWNER
'92 LS-L Pearl~ '92 LS Pearl~ '92 LS-L Teal~ '92 LS-L Silver~ '95 LSi Polo~
'92 JDM Alcyone SVX Version-L 4WS Pearl~ http://www.subaru-svx.net/forum/showthread.php?t=54143
'92 JDM Alcyone SVX Version-L 4WS Ebony~ http://www.subaru-svx.net/forum/showthread.php?t=54117
Reply With Quote
  #1031  
Old 05-10-2010, 04:36 PM
b3lha's Avatar
b3lha b3lha is offline
Phil & Belha
 
Join Date: Aug 2001
Location: Alcyone Limited, Buckinghamshire UK
Posts: 2,671
Re: Memory dump of ECU

Harvey sent me an Aussie TCU a while back. It was FF, same as UK 92 model.

I currently have the following SVX roms.

ECU: D2, J6, M7, 9A,
TCU: FA, FB, FC, FF, MS
__________________
Subaru ECU and TCU Website
1992 Alcyone SVX Version L
1992 Alcyone SVX Version L
1994 Alcyone SVX S40-II
2004 Subaru Legacy 2.5 SE Sports Tourer
1996 Subaru Legacy 2.2 GX Wagon
1988 Subaru Justy J12 SL-II
Reply With Quote
  #1032  
Old 05-10-2010, 05:31 PM
NeedForSpeed NeedForSpeed is offline
Registered User
 
Join Date: Apr 2004
Location: SoCal / Texas
Posts: 1,738
Registered SVX
Re: Memory dump of ECU

Quote:
Originally Posted by b3lha View Post
Harvey sent me an Aussie TCU a while back. It was FF, same as UK 92 model.

I currently have the following SVX roms.

ECU: D2, J6, M7, 9A,
TCU: FA, FB, FC, FF, MS
MadMaxSVX has MT with power mode in his Paraguay car, don't know yet if that is 4ACT like the German, etc. SVX, or 4VTD.

Tony, what are the TCU letters and ECU letters on the S3 JDM?
The S3 TCU uses the N/C solonoid, should be the JDM equivalent to MS, M?.

Phil, the S3 ECU might be different than your S40II ECU, an update.
__________________
Special Thanks to Our Friends and Sponsors:
*
http://www.alcyone.org.uk/ssm http://www.PhenixWheels.com http://www.dba.com.au/
http://www.ClassicSoftTrim.com http://ToyoTires.com/tire/pattern/versado-lx Gillman Subaru of Houston
"QuickChange" http://www.TransGo.com/ http://www.PlanetSVX.com Bontrager Works,

'92 Subaru SVX LS-L Claret ORIGINAL OWNER
'92 LS-L Pearl~ '92 LS Pearl~ '92 LS-L Teal~ '92 LS-L Silver~ '95 LSi Polo~
'92 JDM Alcyone SVX Version-L 4WS Pearl~ http://www.subaru-svx.net/forum/showthread.php?t=54143
'92 JDM Alcyone SVX Version-L 4WS Ebony~ http://www.subaru-svx.net/forum/showthread.php?t=54117
Reply With Quote
  #1033  
Old 05-10-2010, 06:35 PM
Trevor's Avatar
Trevor Trevor is offline
Registered User
 
Join Date: Feb 2002
Location: Auckland, New Zealand
Posts: 5,223
Registered SVX
Re: Memory dump of ECU

Kia ora Phil,

The figures recorded by Tony are valuable and I find them very interesting, particular those covering engine load.

I have a permanently installed pressure gauge registering transmission line pressure. It is clear that pressure becomes adjusted in line with torque, as is being delivered to the transmission by the engine. This observation therefore directly aligns with the engine load figures.

Has your research covered this aspect of things? If so, are you able to advise which sensors provide the signals which are computed, in order to arrive at the figure covering engine load?

Thanks in anticipation, Trevor.
__________________
Trevor, New Zealand.

As a child, on cold mornings I gladly stood in cowpats to warm my bare feet, but I detest bull$hit!

Last edited by Trevor; 05-10-2010 at 06:47 PM. Reason: grand daughter fingered key board.LOL
Reply With Quote
  #1034  
Old 05-11-2010, 06:48 PM
b3lha's Avatar
b3lha b3lha is offline
Phil & Belha
 
Join Date: Aug 2001
Location: Alcyone Limited, Buckinghamshire UK
Posts: 2,671
Re: Memory dump of ECU

Quote:
Originally Posted by Trevor View Post
Kia ora Phil,

The figures recorded by Tony are valuable and I find them very interesting, particular those covering engine load.

I have a permanently installed pressure gauge registering transmission line pressure. It is clear that pressure becomes adjusted in line with torque, as is being delivered to the transmission by the engine. This observation therefore directly aligns with the engine load figures.

Has your research covered this aspect of things? If so, are you able to advise which sensors provide the signals which are computed, in order to arrive at the figure covering engine load?

Thanks in anticipation, Trevor.
Hi Trev. I am not sure exactly what you're asking.

This is my understanding of how it works on new Subaru's. Ours is probably the same but our older ECU technology cannot cope with floating point maths. Therefore there will be some constants multiplied in so that the values can be represented as integers to a certain precision.

M = Mass Airflow is measured in grams of air per second.
R = Engine Speed is measures in Revolutions per minute.

Engine Load is (M * 60) / R = grams of air ingested per revolution of the engine.

As you said, there is some kind of relationship between engine load and torque output.

With regard to the correlation you have observed between torque and transmission line pressure: Obviously engine load and torque are controlled by the throttle plate. It restricts the amount of air that the engine can ingest. Throttle position is also the most important factor that the TCU considers when deciding on the line pressure.

http://www.subaru-svx.net/forum/show...&postcount=247

If my graphs are accurate, the Sol A duty cycle levels off at 87.5% above 20% throttle.

The line pressure is not decided by the engine load. But the engine load and the transmission line pressure are both ultimately dictated by the throttle. Correlation, not Causation. But it certainly makes sense that the TCU would be designed to increase line pressure in line with the torque produced by the engine.

Does that help at all?
__________________
Subaru ECU and TCU Website
1992 Alcyone SVX Version L
1992 Alcyone SVX Version L
1994 Alcyone SVX S40-II
2004 Subaru Legacy 2.5 SE Sports Tourer
1996 Subaru Legacy 2.2 GX Wagon
1988 Subaru Justy J12 SL-II
Reply With Quote
  #1035  
Old 05-11-2010, 07:18 PM
oab_au oab_au is offline
Registered User
Subaru Gold Contributor
 
Join Date: Mar 2001
Location: Coffs Harb, Australia.
Posts: 5,032
Significant Technical Input Registered SVX
Re: Memory dump of ECU

I agree that is the way it uses to work out engine load on our model.
In the later Phase 11 box they use the extra speed sensor on the Turbine shaft to calculate the engine load, by comparing the engine speed, to the turbine speed, to tell how much load the converter is under, the higher the difference, the higher the load. This is a direct relationship to the engine load.

Harvey.
__________________
One Arm Bloke.
Tell it like it is!

95 Lsi. Bordeaux Pearl, Aust. RHD.149,000Kls Subaru BBS wheels.
97 Liberty GX Auto sedan. 320,000Kls.
04 Liberty 30R Auto Premium. 92.000kls.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -6. The time now is 05:29 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
© 2001-2015 SVX World Network
(208)-906-1122