Launch control

Discuss possible software enhancements/changes here.

Moderator: Matt

Matt
Site Admin
Posts: 8191
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Launch control

Post by Matt » Thu Jan 22, 2015 11:41 am

Confirmed we have a spare input on this ECU

There is a feedback flag (B8F8#20 = Bit 5) for using the calibration screw for the non-cat models to use this. It adds an offset after the MAF VQ lookup is done to adjust overall enrichment (primarily for idle) which is used before K constant

Other models dont use the feedback flag but still look at the value (which is not connected). I've removed this completely so we can use for a spare auxiliary input :)

Matt
Site Admin
Posts: 8191
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Launch control

Post by Matt » Thu Jan 22, 2015 6:46 pm

Many many hours later and its all done and tested on the bench! Fortunately (in some ways) January can be rather quiet so gives me time to catch up on development

I'll run a patch harness in my car tomorrow and try the ECU in the vehicle, but its passed all the tests in my test suite now

Code is half written for VL RB30/Z31 VG30 but I need to port 6303 backwards to 6802 processor so that will take some extra time

Tengis
Posts: 37
Joined: Thu Oct 23, 2014 2:21 am

Re: Launch control

Post by Tengis » Fri Jan 23, 2015 7:56 pm

Very nice. I haven't messed with launch control yet but I would have killed for something like this on my other car.

Do you work on Nistune full time or do you have a day job? Just curious.

Matt
Site Admin
Posts: 8191
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Launch control

Post by Matt » Fri Jan 23, 2015 10:51 pm

Looks okay so far but I messed up some code today when doing porting from 6303 CPU to 6802 CPU (for the Z31/VLT models) so need to fix that up (conditional compilation got messed up). The switching for the launch control works but its a bit slow. I'll have to move where the routines are called

I used to do Nistune part time (after my normal working hours upto end of 2010) and then got made redundant from my full time job. Nistune has been busy enough to support us so I've been working full time basically from 2011 onwards so I now have more time to catch up and do firmware updates

The feature pack writing started about March last year so its almost been 10 months to do the coding and testing so far whilst also providing support, packing orders, maintaining software etc. The hardest part is disassembling the existing code, and trying to slot in new code without breaking anything (many variables etc are used by the existing ECU so it is easy to cause problems with a simple coding error)

I expect CA18 should be fully tested by end of next week and the VLT not long after this

Tengis
Posts: 37
Joined: Thu Oct 23, 2014 2:21 am

Re: Launch control

Post by Tengis » Sat Jan 24, 2015 2:04 am

Nice. Do you have any future additions you will be attempting to implement?

Matt
Site Admin
Posts: 8191
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Launch control

Post by Matt » Sat Jan 24, 2015 7:23 am

Given I have most of the disassembly and patching structures written it is now easier to add more code. I did consider recompiling entire code bases but with so many variants it does not seem to be worthwhile. I have several main new features I would like to add but it will be restricted to certain core models where it would be financially viable. Each model of vehicle has different code so I can only spread the updates so far

Feature list:

- MAP sensing (the next most requested option). Including using spare AUX inputs for IAT compensation. This would be a fairly large job
- Adding programmable output control (ECUs with spare inputs such as Z32 AIT output) for triggering nitrous control etc
- Boost control added to R34/WC34 and also BNR32. Simplifying boost control on S14/S15 also
- Boost by ethanol content scaling
- Injector latency table by voltage (replacing the single @ 14V). Low priority

Spending time on adding new features is only going to be worthwhile if people actually use them (as opposed to wanting them) and if it generates additional sales to justify the time, effort and cost in developing those features. It is only just myself working on the software and firmware.

However firstly I have requests weekly to support newer models such as the Nissan Patrol and M35 Stagea. So I'm going to start looking into these once the Feature Pack 1 work is completed.

Russ84NA
Posts: 66
Joined: Fri Mar 31, 2006 11:36 am
Location: Ohio, USA

Re: Launch control

Post by Russ84NA » Sat Jan 24, 2015 7:34 am

Thanks Matt

Matt
Site Admin
Posts: 8191
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Launch control

Post by Matt » Sat Jan 24, 2015 8:48 am

Back to the launch control...

36Fxx (JDM) rev1 limiter is the normal soft limiter, rev2 is the hard limiter (when not on knock maps... that is what the rev3/rev4 were for)

39Fxx/44Fxx does not seem to use the soft limiter? Anyone noticed this?

Russ84NA
Posts: 66
Joined: Fri Mar 31, 2006 11:36 am
Location: Ohio, USA

Re: Launch control

Post by Russ84NA » Sat Jan 24, 2015 8:55 am

Can you explain what you mean by soft and hard limiter.
I used to have a rev limiter that would "bounce" when I hit it and keep going. Now when it hits the limiter the car stalls for lack of a better term until the revs drop then it kicks back in.
I much prefer the bounce rev limiter. What could I have changed to not have that anymore?

Matt
Site Admin
Posts: 8191
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Launch control

Post by Matt » Sun Jan 25, 2015 1:03 pm

One limiter is the 'soft' limiter which cuts temporarily and then recovers. The hard limiter cuts all fuel until an RPM recovery point (say 2000rpm) which is more noticable

I'm not sure what parameters you have changed to do this. Check both limiters if you have them listed

Russ84NA
Posts: 66
Joined: Fri Mar 31, 2006 11:36 am
Location: Ohio, USA

Re: Launch control

Post by Russ84NA » Mon Jan 26, 2015 5:04 am

OK now I think I understand the problem. I thought that REv Limt 1 was the cut and Rev limt 2 was where it kicked back in.
So I had #1 set to 6500 and #2 at 6450.
I guess if I reset #1 at a point lower than #2 it should be OK.

The Safety limiter is set to the max of 12750...What is this for and is there any reason to have it lower?
The fuel cut and Recovery... Temp vs RPM
The cut starts at 2100 and decreases as the temp increases to 1500
Recovery is about 200 rpms below the cut.

Do these effect the point at which the fuel starts after either limit cut?

Topdog781
Posts: 51
Joined: Wed Sep 15, 2010 1:14 am

Re: Launch control

Post by Topdog781 » Mon Jan 26, 2015 10:18 am

So .... is launch control avalible yet? If it is which vehicles is it avaliable for?

Vetal
Posts: 128
Joined: Tue Jun 26, 2007 10:39 pm

Re: Launch control

Post by Vetal » Mon Jan 26, 2015 7:09 pm

Can't advise on cat vs non-cat ECU's, since all CA18's I've seen are CAT models, non-adjustable AFM

Matt
Site Admin
Posts: 8191
Joined: Sun Jan 29, 2006 1:45 am
Location: Adelaide, Australia
Contact:

Re: Launch control

Post by Matt » Tue Jan 27, 2015 8:56 am

Launch control is availble for vehicles listed here:
viewtopic.php?f=12&t=2874

Going to start doing more in vehicle testing today for the CA18. I'm having trouble getting the HPX (which works fine with S13-S15 ECUs) running on the CA18 ECU. Might try swapping to an R35 so I can at least drive the car

Vetal
Posts: 128
Joined: Tue Jun 26, 2007 10:39 pm

Re: Launch control

Post by Vetal » Wed Jan 28, 2015 9:16 pm

Wow good bit of development going on here :) :)
Once again, what are all 4 rev limiters for? I just move them all at once if I need to change rev limit...

BTW just had a thought... Would this (launch-control) work as a flat-shift feature? :?:

Post Reply