Jeep SBEC PCM tuning (91-95)

@convx4 You'll be better off with MPTune that can be found on TM. Mine is geared at the 3d table based Jeep computers.. the SMEC uses all 2d tables. Wowzer over on TM is who you should talk to.. it may take him a minute but he can certainly map out the tables and import it into MPTune to where it can be edited (fuel/spark, injector latency, etc). I have to make time to work on the Jeep stuff, so as much as I'd like to take on another code set, MPTune is geared toward SMEC whereas mine is geared at the SBEC-II/III flash ecu's. It's not terribly hard to map an ecu in MPTune, just time consuming and involves going through and basically identifying fuel/spark/sensor routines & memory locations (in assembler language, with no comments to help guide). It should be similar to an existing code base which will make it easier for wowzer to work with since he's more familiar with that than I am.
 
A-Kelley Thanks for your reply. I understand not taking on to many projects. I will see if Wowzer can help me along. I'm just an analog kinda guy.
 
If you were to disassemble it and compare it to the other code that is similar you'd fairly easily figure it out I believe. I'm going from square 0. SMEC has been dissected to death.. a "relocatable disassembler" would be the trick for smec assuming they shared routines but they may not have.
 
A-Kelly
I had the same thought of comparing like cals. One reason I bought up Thanks for the lead on the relocatable disassembler.
 
Well, sorry but I got tired of waiting for any word on this project.

Andrew you should realize that you need to get out a device that someone can actually use to change *any* small setting on their ECU at all. Writing a whole all-bells-and-whistles piece of software is not required as a first step. The first step is that people should be able to buy something from you to, say, turn off the security system.

Once anyone can do a small change on their ECU in their own garage, then they can give you feedback on what other features they would like. But hoarding something for years which is quite useful just as is, for the reason that it is missing features, is not the best approach.

I am still willing to pay good money just to turn off the security. So please contact me when you have this available for purchase.

As a different solution, I made my fuel pressure regulator adjustable.

Here is my the video for making your own adjustable fuel pressure regulator out of a stock one. You will need a small lathe:

 
Hello, does anyone know on 781 bin file where can i find the adress for TCC lockup, to lock it up sooner or later?Thanks
 
thanks for reply.Mine is from 95 and has a black sbec with one plug.I saw in electrical diagram that pin 54 from ecm goes to TCC solenoid.is this correct?
 
Hi, I know I'm probably a little late to the party as I've been looking for a tuning solution for my 1992 Dakota and I happened to come across this thread via Google.
I'm currently using a 94-95 socketed SBEC with an ST 64k EEPROM. I was able to get a custom tune from a Chrysler engineer that worked with my dad after I built my 360 for the truck. Later I built a 408 and was able to get a tune through B&G Performance in Warren Michigan from Dave Kasper prior to him joining another outfit. I'm in the process of doing a cam swap and I would like to be able to do some tuning following the swap. I had some communication with Wowzer from the turbo Mopar world. He was able to do a sort-of disassembly for a template but it's not functional. I contacted him a couple years later and he stated he was kind of embarrassed that he had forgotten what we were in the process of doing. I made a reply back and I haven't heard anything since. Long story short - that's what brings me here. Would the subject utility work on the 94-95 truck calibrations as well?
 
Yes it will . But like with MPTune, the fuel and spark maps will need located. I was looking at pcb layout software so I can get the interface boards made.
 
a_kelley said:
Yes it will . But like with MPTune, the fuel and spark maps will need located. I was looking at pcb layout software so I can get the interface boards made.
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Correct me if I’m wrong but the fuel and spark 3D maps are typically 9x17 in size in the .bin....I think. I’m specifically looking for the rev limiter. As I understand it, RPM is hex to decimal * 32. Probably preaching to the choir but it’s just what I remember from initially diving into this stuff. For PCB layout software I typically use KiCad or Fritzing. Both free and powerful.
 
That's correct. I'm not sure on rpm or any other "real" values. I located the limiter in the i6 stuff, the v8 may be similar but not certain. If it's got 3d tables it might be.
 
a_kelley said:
That's correct. I'm not sure on rpm or any other "real" values. I located the limiter in the i6 stuff, the v8 may be similar but not certain. If it's got 3d tables it might be.
Click to expand...

Can you modify the calibration and save it to a .bin or do you have to bootstrap the SBEC and download?
 
Right now, it directly edits the .bin. the interface is set up to automatically boot the ecu when you hit program, just turn the key on. It will program ST chips and atmel chips directly in the ecu, no removal required. St takes about two minutes to flash. Atmel takes about ten seconds. I could modify the board some to allow the bin to be saved to the board and then directly flash the ecu without the computer.. if they're enough interest in that feature. Same for data logging
 
a_kelley said:
Right now, it directly edits the .bin. the interface is set up to automatically boot the ecu when you hit program, just turn the key on. It will program ST chips and atmel chips directly in the ecu, no removal required. St takes about two minutes to flash. Atmel takes about ten seconds. I could modify the board some to allow the bin to be saved to the board and then directly flash the ecu without the computer.. if they're enough interest in that feature. Same for data logging
Click to expand...

Which ST chips are you referring too? I was under the impression that they weren't flashable through the SBEC. If in fact they are I'd like to switch.
 
They aren't flash able with MPTune. My hardware and software can in vehicle and that's what makes it different. I'll look and see what they are when I get back home.. wanna say they are st27c356. This interface and soft can flash most of the stock 95 ecus.
 
a_kelley said:
They aren't flash able with MPTune. My hardware and software can in vehicle and that's what makes it different. I'll look and see what they are when I get back home.. wanna say they are st27c356. This interface and soft can flash most of the stock 95 ecus.
Click to expand...

Sorry for the barrage of questions, but I get my hopes up a little when I see that someone has been working on an application of this type. Is this something that is accessible executable or is it still in coding/development stages?
 
It's still in development but the programming works 100% just need to make some interfaces. Software will be free, possibly open source except the comms but that will be in a DLL or stand alone. The editor needs work on it as does the logging feature. It works but needs a couple bugs worked out, but nothing that would need the hardware to change.

Is the standalone feature to program something that people would be interested in or is it good enough having to use a laptop?
 
a_kelley said:
It's still in development but the programming works 100% just need to make some interfaces. Software will be free, possibly open source except the comms but that will be in a DLL or stand alone. The editor needs work on it as does the logging feature. It works but needs a couple bugs worked out, but nothing that would need the hardware to change.

Is the standalone feature to program something that people would be interested in or is it good enough having to use a laptop?
Click to expand...

Personally I have no issue using a desktop/laptop application, probably since I’m in front of a laptop most of my day at work. For me, I’d just need a way to make adjustments to fuel, timing, and as I mentioned earlier, the rev limiter. From there export the .bin out to my chip burner or emulator. I suppose there’s people that would like standalone as well, but I’m sure it’s about capability and preference.
 
Certainly... I was contemplating changing over the interface used on USB<->board from emulating a COM port to HID, but that doesn't affect the board's design, as it can be updated over USB. Presently it does flash both Atmel chips and ST or ST compatible chips that require HV to program. The Atmel chip is an AT28C256 which requires some modifications to the SBEC board (or thge boostButton adapter) The ST compatible chip is a 28F256A-200 (mine are Intel chips, but they are electrically and pinout compatible to the ST 28F256) The flash chips do not require UV erasure as they are flash memory. The Atmel chips are EEPROM, which is why they program so quickly. I didnt actually ever time the ST programming, but its roughly two minutes and can be done in vehicle, by connection to the DRB plug under hood, or do like I did and bring the connector inside the vehicle and run wires to the plug. The interface requires 12v, RX,TX, & Ground connections to the vehicle, a 9v battery(unless I design a boost converter to generate the needed voltage, but I think it taking a 9v battery is acceptable considering it should leak before it gets discharged). Proghramming is verified as it happens, so its guaranteed to be correct when successfully completed. The logging routine presently has a quirk where sometimes it does not communicate unless the car is reset, and I'm still debugging that. Logging also presently only records the data (tied to the HID/COM port decision).. Intentions are for the logging to be able to be recorded, as well as viewd in real time, just like on a modern scan tool on a modern car. I think that adding a memory chip and moving the programming/logging routines to the interface would be nice to allow the logging to occur without having to have the laptop in the car and hooked up. Also would like to add a button to the interface if I do that so that way a "flag" can be added if there is a fluke event that occurs to aid in the diagnosis instead of needing to locate it manually. Also I heard that the v8 code was developed by a different team than the i6 code, and it was before OOP and reusing code was real popular, so there may be large differences present. Are you mainly interested in the editor or the programming/logging interface or both? If you want to send me a copy of the .bin you have, I can have a look at it and see if I can't locate the rev limiter (I assume you already have a way of dumping/programming based on info in your previous post.

Future intents of :
  • adding a knock sensor for performance tunes in the interest of piston/ring longevity (naturally, without a KS, the stock tune is rather mild, and could be brought to the bleeding edge if it had a KS.. I know the TM/TD SBEC had KS; that being said, I havent delved into it to see if there would need to be an analog front end to buffer the signal coming in for the ECM to use it or if the electronics were already present and just unused.. For example, your v8 pcm can be used to run a i6 by reflashing it and installing, but not a i6->v8 because the i6 lacks the two extra injector drivers)
  • 2 bar capability for boost (the reason i started this project, to allow supercharging a SBEC 4.0)
  • deleting security (@GarageBuild)
  • modifying rev limiter/cruise control min/max
  • Native wideband support, to allow logging of WB AFR, while letting the PCM use that as the o2 feedback
  • moates emulator support (seems like thats the ticket to rapid devel/logging.. i bought a logic analyzer to see whats going on with some things [mainly my SBEC stimulator] but the logging of execution flow would be nice. I've toyed with the idea of creating an emulator capable of simulating all inputs/outputs, like a glorified 68hc11 sim, but dedicated to SBEC for the purposes of being able to trace/simulate modifications)
Another option I contemplated was bluetooth interface to my board, eliminating the need for physically connecting to it. However, I think the USB interface is pretty well the ticket. In addition, switching the interface over to HID/BT may allow use of a tablet/cell phone to be used for logging/editing/flashes though I don't know the first things about writing an android app. I'm developing all the PC software in VC6 and the micro stuff in MPLAB 7.3 / MCC18 3.02. I'm old school. My laptop runs win7. I prefer w2k pro.
 
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  • Based on my experience the 92-93 V8 trucks used a 32k M87C257 address latched UV flash EPROM. The Boost Button flashable chip basically replaced this and will work in the 92-93 truck SBECs.
  • After finding out that Shelgame actually lived right around the corner from my work, I drove over there and purchased one directly from him. I was a little new to the SBEC stuff and I was totally unaware that it wouldn't work in my 94-95 SBEC. I ended up selling it with a 92-93 SBEC later on since it wasn't capable of using my existing flash.
  • I'm currently using a 94-95 SBEC with an SST 27SF512 28pin EEPROM. Since it's not address latched I can use the .bin on a Moates Ostrich. I rarely run it on the Ostrich as I originally bought it as more of a hacking tool to see if could see what addresses or 3D maps of the .bin were accessed by the 68HC11. I used TunerPro to do this as it has Ostrich support as well and an address watch function. I played around with it for a while but didn't get very far.
  • I'm more so interested in the editing/programming feature of the software right now. I have a wideband O2 with a serial connection and an analog output if I want to datalog AFR.
  • I can certainly send you the .bin. How would you prefer that I get it to you?
 
91-93/94 boards with the 87c257 rely on the 8 bit address latch on the chip. Rob used to have a "latch board" which was an adapter to add a latch to allow use of atmel chips. There's actually 3 variants I've seen:
  • Early boards used the 87c257
  • Later with latches in the sbec but not flash memory
  • Latest with latches & flash (early used Toshiba chip which I cannot find the programming spec on, I had two Toshiba sbecs but could not get either to program)(later used the St 28f256, which this interface will program installed)
This interface/software supports atmel chips, ST chips and compatible chips. The flash chips require high voltage to program which is why the boost button cable cannot program them. It can only program the atmel eeprom, as it does not require hv and also, the BB cable requires you to manually enter program mode. with my interface/software, you simply turn the key on and it automagically recognizes the type of chip and will program and verify at the same time. BB/MPTune requires verification as a separate step, adding to the time required to program, although the atmel is much faster than the flash memory, due to actual internal chip programming time. If you look back in this thread you can find pictures of my modified board that uses an atmel chip, although I wouldn't run it in a vehicle because I removed the majority of the potting to help me figure out the processor, wiring, outputs, etc.
 
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