CSL '0401' Program Binary Disassembly Notes

[ac427]

Not a lot of losses at part throttle, which is where this would be most useful I think. Then tune WOT without the HFM by AFR and open the flap, redo AFR for the flap open case. All the acronyms, sorry!

No worries. It would certainly be an interesting experiment.

Speaking of calibration, it would be interesting to know how the CSL IAT is coded for the heat soak issue. I mean, BMW could have placed it anywhere but they put it in a place where its output is bound to be skewed by the heat from the engine. Obviously they accounted for this in coding but i wonder if there is a point the output from the IAT just becomes useless?

[karter16]

What year did the E46 M3 GTR come out?

It was a V8. I'm not sure which ECU it used though.

Also, which DME did the E39 M5 have, probably a previous generation MSS5x ECU.

GTR was 2001 I think, so before the CSL. The DME in the race version was entirely separate, not sure what they did in the strassenversion but suspect it would have been a derivative of that.

The E39 M5 was the MSS52.


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[Bry5on]

True, I guess you could mount a MAF anywhere near the actual air intake path and then calibrate for loses?

Not a lot of losses at part throttle, which is where this would be most useful I think. Then tune WOT without the HFM by AFR and open the flap, redo AFR for the flap open case. All the acronyms, sorry!

[ac427]

Easy enough to make an adapter for the non-CSL MAF to the lower snorkel, then just leave the flap closed.

True, I guess you could mount a MAF anywhere near the actual air intake path and then calibrate for loses?

[Bry5on]

Are MAF's available in the CSL snorkel diameter?

It would interesting to implement an MAF for part throttle quality research.

Apologies, i could have put these these as one post but i was using the phone on the train home.

Easy enough to make an adapter for the non-CSL MAF to the lower snorkel, then just leave the flap closed.

[ac427]

Are MAF's available in the CSL snorkel diameter?

It would interesting to implement an MAF for part throttle quality research.

Apologies, i could have put these these as one post but i was using the phone on the train home.

[ac427]

What year did the E46 M3 GTR come out?

It was a V8. I'm not sure which ECU it used though.

Also, which DME did the E39 M5 have, probably a previous generation MSS5x ECU.

[karter16]

karter16

Is there anything that would suggest BMW used some of the code to develop the one-off E46 M3 CSL V8? I think that Terra said that the MSS54/HP has spots on the circuit board to drive two extra cylinders. Also, the S62 did run on MAFs.

I can't say for sure but all the code I've seen is capable of handling 8 cylinders (eg all the TZ and TI arrays are for 8 cyl etc), plus has 2x HFM A/D converters. Standard M3 just uses HFM1 (pin 1 on X60003), HFM2 is pin 18 and 0401 uses this for the MAP sensor and HFM1 for flap pot. As it stands 0401 as is wouldn't run it because HFM2 is assumed to be MAP sensor, but certainly could have been a derivative I would imagine.

Pretty sure a lot of the code is fairly common across MSS54 and MSS52, plus funktionsrahmen suggests at least some fmodules are ported to/from MSS60 project.


Edit: to be clear, MSS54 software in general has provision for 8 cylinders, which I presume is due to similarity with MSS52 software.

[0-60motorsports]

karter16

Is there anything that would suggest BMW used some of the code to develop the one-off E46 M3 CSL V8? I think that Terra said that the MSS54/HP has spots on the circuit board to drive two extra cylinders.

Dream E46 M3 right there and it was SMG too. LOVE IT!

[Slideways]

karter16

Is there anything that would suggest BMW used some of the code to develop the one-off E46 M3 CSL V8? I think that Terra said that the MSS54/HP has spots on the circuit board to drive two extra cylinders. Also, the S62 did run on MAFs.

[karter16]

I'll bet they tuned the car with an HFM in the loop at some point to get the cam baselines

Good call - that makes a lot of sense.


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[Bry5on]

I'll bet they tuned the car with an HFM in the loop at some point to get the cam baselines

[karter16]

Fun fact (which other people may already know, I just didn't) - the final RF calculation function in 0401 actually has provision for use of an HFM (MAF) sensor. The HFM sensor is assumed to to be plugged in to HFM1 (which in 0401 default config is the potentiometer for the CSL flap), but there are a number of parameters which can be set which configures the HFM1 A/D converter and ring buffer for a MAF sensor and derives the final RF from the ML value from HFM1. This is interesting as the final RF function in 0401 is not a copy/paste job from the standard MSS54HP code (e.g. it's an intentional inclusion, not a failure to omit). What I haven't looked into yet is whether any of the HFM tables differ from MSS54HP. I'm presuming that it would be calibrated for the standard M3 HFM sensor and cross-sectional area.

Here's the relevant line from the final RF calc function which I've posted before:



And here's the function which reads the A/D converter ring buffer:

[karter16]

Have identified the curve at 0xD002 - it describes the maximum torque to be applied by the Moment Manager in the event of a CAN SMG error state being stored in CAN_ED_SMG. The x axis is V (in km/h) and the y axis is torque (in Nm).

I've named the curve kl_md_can_ed_smg_max.



The curve is referenced in the function at 0x0001b0c2 which I have named md_can_ed_smg_max_calc()



This function in turn is run in one of the timed tasks (pretty sure it's the 20ms task but not 100% sure yet) if the gearbox type is SMGII.



and md_can_ed_smg_max itself is used in the Torque Limitation function of the Moment Manager.

[karter16]

Have published the XDF - figured it was worth it's own post so you can find that, along with the download link, here: https://nam3forum.com/forums/forum/s...p-csl-0401-xdf