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Re: Challenge: add Audi "trigger wheel" to code

Posted: Wed Aug 03, 2011 7:47 am
by jsmcortina
As currently coded the I/O is as follows:

PT4 used for hi-speed flywheel teeth
"crank" tach-in used for single flywheel pin
"cam" tach-in used for hall cam

The choice of PT4 and "crank" for the two flywheel signals allows for code sharing with the Nissan CAS and Optispark modes. Presently the cam input is fixed on the "cam" input, but JS10 could be allowed if desired.

The high frequencies on the two flywheel sensors do present an issue and the VR conditions need to be up to the job as phase drift will likely lose sync.

I've been testing on the bench with the 135 tooth + 1 pin flywheel signals only (not re-written the JimStim for the tertiary cam tach) and so far it _appears_ to work up to the max speed I've generated on the stim = 5900rpm.

James

Re: Challenge: add Audi "trigger wheel" to code

Posted: Wed Aug 03, 2011 8:55 am
by elaw
jsmcortina wrote:As currently coded the I/O is as follows:

PT4 used for hi-speed flywheel teeth
"crank" tach-in used for single flywheel pin
"cam" tach-in used for hall cam
I can probably test that way because I have Jean's board with the two VR conditioners on it. But as I'm sure you know, for this to work with minimal added circuitry, the two MS VR conditioners (on the V3 board and on the MS3X) would have to be used for the flywheel signals.
jsmcortina wrote:The choice of PT4 and "crank" for the two flywheel signals allows for code sharing with the Nissan CAS and Optispark modes. Presently the cam input is fixed on the "cam" input, but JS10 could be allowed if desired.
JS10 would be good for me since my MS is currently set up that way, but I can switch it if necessary.

jsmcortina wrote: I've been testing on the bench with the 135 tooth + 1 pin flywheel signals only (not re-written the JimStim for the tertiary cam tach) and so far it _appears_ to work up to the max speed I've generated on the stim = 5900rpm.

James
Great! FWIW, factory redline on the Audi 20-valve engines is 7200.

Re: Challenge: add Audi "trigger wheel" to code

Posted: Wed Aug 03, 2011 9:48 am
by jsmcortina
Making the cam input JS10 instead is a trivial code change.

The trouble with using the existing cam tach input on the MS3X and likely the mainboard crank too is that the standard component values aren't designed for this many teeth and will need changing. That's all part of this alpha testing and development though.

James

Re: Challenge: add Audi "trigger wheel" to code

Posted: Wed Aug 03, 2011 10:30 am
by elaw
Fair enough!

By the way, I think I probably overestimated the difficulty of making the changes to my system needed to test this. So whenever you have some code you think is usable, feel free to send it to me and I'll give it a try.

PS: if that code was based on alpha 13 it would be great, since that's what I'm currently running.

Re: Challenge: add Audi "trigger wheel" to code

Posted: Wed Aug 03, 2011 10:34 am
by racingmini_mtl
Eric,

Let me know if you want to try a MAX9926-based solution for the VR signals.

Jean

Re: Challenge: add Audi "trigger wheel" to code

Posted: Wed Aug 03, 2011 10:44 am
by elaw
Jean,

Thanks for the offer but for now I'm going to stick with what I have because it works! I haven't had anything that even remotely resembles a triggering problem in this car for months. :yeah!:

For testing the new code, I can easily grab the signals coming out of the LM1815s and route them to the appropriate places - I think I can do it in a way that will allow me to revert easily if the new code has any issues.

Re: Challenge: add Audi "trigger wheel" to code

Posted: Wed Aug 03, 2011 10:46 am
by jsmcortina
Looking forward to seeing a workable "recipe" for using these wheels. If it works better with the inputs swapped around (e.g. a VR board inside the case) then the code can be changed.

James

Re: Challenge: add Audi "trigger wheel" to code

Posted: Sat Aug 06, 2011 1:46 pm
by julian944
Sorry for the question which is off topic, but I'm just thinking about my configuration.

Is it right that the amount of teeth on the flywheel divided by the number of cylinders must be an integer?

So I get a problem with my 130 teeth flywheel on a 4 cylinder engine right? (Porsche 944).

Thanks for your help

Julian

Re: Challenge: add Audi "trigger wheel" to code

Posted: Sat Aug 06, 2011 5:58 pm
by jsmcortina
Assuming we can get it working, because the code is custom then strange numbers can be supported too.

James

Re: Challenge: add Audi "trigger wheel" to code

Posted: Mon Oct 10, 2011 12:06 pm
by jsmcortina
Anyone tried out alpha 14 ?

James

Re: Challenge: add Audi "trigger wheel" to code

Posted: Mon Oct 17, 2011 6:57 am
by julian944
Hello,
well I don't have tried it yet, I just got my ms3, but I'am thinking about my configuration and I need some help.

Porsche 944 with 130teeth wheel for crank speed and one single pin on crank for the position, and absolutely stock ms3 with ms3xboard from diyautotune.com

I've loaded alpha14, and I have seen flywheel tri-tach, I guess this is the right one?

PT4 used for hi-speed flywheel teeth
"crank" tach-in used for single flywheel pin
"cam" tach-in used for hall cam
ok so far?

PT4 is normally used for logic output, so do I have to make some internal hardware changes in my ms3, or is everything changed in the code?
Normally I thought I need a VR-conditioner ? Do I need to build this on the pt4 input?


So if I dont use any cam in, I just can choose "use cam signal if availible" OFF, and code is still working?
tertiary tach input belogs to the cam signal right?

@James, you said you tested it on the bench with the stim, ist the stim simulating VR or hall -sensors? you have been able to rev up to 5900, did you made any hardware changes on the tach-inputs?

Thank you very much for your help.
Julian

Re: Challenge: add Audi "trigger wheel" to code

Posted: Mon Oct 17, 2011 7:07 am
by jsmcortina
You need to make an external VR conditioner circuit and connect to the PT4 pin on the MS3X. This is actually an input or an output. No change is needed on the MS3X.

Hopefully Eric will chime in with anything else that he has learned.

The processor itself does not know the difference between VR and hall inputs - they both look like a square wave one they arrive at the processor.

James

Re: Challenge: add Audi "trigger wheel" to code

Posted: Mon Oct 17, 2011 7:22 am
by julian944
Ok, and when I have a hall-sensor which already delivers a square wave then I don't need such a condition right?

For my application I just need two vr-conditioners, is it possible to use the standard ms3x-board conditioner and connect this curcuit to the pt4 pin?

Regards Julian

Re: Challenge: add Audi "trigger wheel" to code

Posted: Mon Oct 17, 2011 7:50 am
by dontz125
You always want to use a conditioner of some sort. Directly connecting the processor to a sensor "In the great outdoors' is a good way to buy a new processor - shorts, surges, loose wires, small animals, you name it, all of a sudden you've got 12+ volts coming down a wire into a pin that doesn't like anything over 5. Oops ...

Re: Challenge: add Audi "trigger wheel" to code

Posted: Tue Oct 25, 2011 1:54 pm
by elaw
jsmcortina wrote:Anyone tried out alpha 14 ?

James
James,

Well... finally... yes! Sadly, the addition of the noise filter doesn't seem to have changed the behavior on my car. The engine will only start on about 50% of attempts, but once it starts it always runs perfectly. I took a bunch of logs, I'll email them to you with the associated .msq.

Re: Challenge: add Audi "trigger wheel" to code

Posted: Tue Nov 01, 2011 2:53 pm
by jsmcortina
Spent some hours working on this today. I wrote a tri-tach mode on the JimStim and eventually found a couple of tiny but important bugs in the code.
a. MS3X cam wasn't working as the cam input and was screwing up the spark outputs in this mode.
b. The cam input wasn't actually being checked due to a code error. Hence 50% of the time it would start on the wrong phase.

So, as of now it appears to work ok on the bench, which it didn't earlier.
(In my previous testing I only had two tach inputs, so was unable to test it fully.)

James

Re: Challenge: add Audi "trigger wheel" to code

Posted: Sun Nov 06, 2011 12:39 pm
by elaw
James,

Just tested this out on Alpha 15, and it appears we have success! :yeah!:

I'll email you with the details, but I just wanted to thank you here for the effort you've put into this.

Re: Challenge: add Audi "trigger wheel" to code

Posted: Wed Nov 23, 2011 3:25 pm
by savagerocco
Have you run this long enough to get a feel for it?

Re: Challenge: add Audi "trigger wheel" to code

Posted: Wed Nov 23, 2011 4:56 pm
by elaw
It's still not 100%. It's working well enough that I actually drove the car for a few days using it. But every now and then (maybe 5 times in a 20-minute trip) the engine would "hiccup", as if it missed one injection pulse or ignition event, and the log would sometimes show a single point with zero RPM. So I switched back to using the divider board.

I'm a little reluctant to keep modding the hardware to switch back-and-forth between triple trigger and the divider board, so I've got a request in to James to be able to change one of the triple-trigger inputs so I can make a permanent wiring change that will support both modes. That way I can test just by changing settings in the software.

Re: Challenge: add Audi "trigger wheel" to code

Posted: Wed Nov 23, 2011 5:12 pm
by jsmcortina
This mode certainly proved and still proves to be hard work. I've been too busy of late to get to Eric's request.

James