Cam-aware siamese code, now with full sequential staged injection
Turbo Mini Forums

I look forward to see pictures of your finished setup. And to hear of another engine running the siamese code.

In any case, you want to take it step by step especially since this is still experimental in that we don't know yet how everything need to be set. Once there are one or two running engines then things should be easier since there will be a baseline.

Oh, as for going mad, that I can't tell one way or another...

Jean

http://www.jbperf.com/

Schrödinger's cat - so which one am I ???

I have now added the 4-driver capability and associated full sequential with staged injection. I have attached the s19 file and the MT ini file. This version also has the corrected injector numbering: injector driver 1 to intake 1/2 and injector driver 2 to intake 3/4. The injector driver #3 is for staged injection in intake 1/2 and injector driver #4 is for staged injection in intake 3/4.

I will be making a web page to show the needed modifications (as per pic in my previous post + where to connect the 4 new drivers on the board) and how to setup the different parameters in Megatune (only for the ones specific to siamese code).

It is possible that there are still bugs but the behaviour on the bench seems quite good.

Jean

Attachments:

104.63kb

http://www.jbperf.com/

Sturgeo has just finished building the JimStim and is now nagging me to get the Megasquirt out of the car!

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Jean,

I have PM'd you re. the P&H board as I will be sticking with low z injectors.

Rod.

Schrödinger's cat - so which one am I ???

We have now got the MS setup with the latest code and running fine on the JimStim.

Sturgeo is just manually filling in the VE table as we could not import the previous table.

Hopefully we will give it a try on the engine in the morning.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

That's great! Let me know if you find anything's amiss with the code.

Do you have the cam sensor in place? And if so, where did you position it with respect to the crank missing tooth?

Jean

http://www.jbperf.com/

The cam sensor is fitted but not timed.

Where would it be best set?

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Schrödinger's cat - so which one am I ???

As I mentioned previously, between 30 and 90 degrees before the crank missing tooth on the ignition rev for cylinder 1. Exact timing is not critical but you don't want the cam signal to arrive at the missing tooth and you want it close to speed up sync.

Jean

http://www.jbperf.com/

Apologies, but still suffering from an overload of good food, wine, art and culture

Jean, Thanks.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Jean,

Must say that your JimStim is brilliant.

I don't know exactly how he has done it but Sturgeo has got it all set up so that at low rpm, you can see each injector firing twice and the sparks in the right place - all nicely synchronised.

Just hope it works for real tomorrow.

For the injection timing, I used the same sort of timing values that we developed previously. We will need to do some road tests to fine tune the table.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Paul,
Thank you. I must say it's an invaluable tool for me.

Are you using the additional injector drivers with the peak&hold board or the standard injector drivers? If you use the additional drivers you will have to be careful when uploading new code in the car because it is possible that one or more injector stays on for the upload duration which would easily flood the engine.

This is not due to the drivers themselves but to the monitor code which does not initialize all pins. It's fine with the standard drivers because they NAND 2 pins but with the additional drivers each pin controls an injector. So you should remove the injector fuse before loading new code. The same needs to be done for the coils anyway (not siamese code specific but MS2/extra "feature").

Jean

http://www.jbperf.com/

I'm just using two injectors for now on the NA 998.

If we can get the code to give us close AFRs across the range, then I will add the turbo/intercooler etc.

I'll see if it will idle OK with four injectors wired to the two drivers to start with. If not then I'll modify the board for four injector drivers.

I'm sticking with high impedance injectors, so may not need the P&H board.

I'm hoping to have it running on the 200+hp 1293 turbo by the summer.

Thanks for the heads up on the injector fuse.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Jean,

Possibly a silly question but here goes...

Is it OK to load/use the new version on an MS that doesn't yet have the four drivers as the CPU pin output functions will be different ???

I assume the answer is "yes, its OK" because the pins are currently NAND'd (so the new code won't know its only driving two outputs instead of four) but I'm also concious that you said earlier that the clock circuitry on the mainboard would also need removing.

Or does the clock circuitry not get in the way until the two link wires are installed from the NAND chip ???

Sorry, I've worded that very badly but hopefully you will see what I mean.

EDIT - I've just re-read you post of Jan 12th,
"The modifications to the MS2 card are intended to be as non-intrusive as possible. The schematic for the MS2 card can be found here. The intent is to run in parallel to the current driver to minimize the needed changes. So it would require soldering small wires to connect pins 1 and 4 of the 74HC00 to pins 4 and 5 of the card. These last 2 pins are connected to the crystal which is only required for MS1 so they can be used for another purpose (as long as the crystal and the associated components are left out).

Then 2 of the 4 drivers of the p&h board would be connected to these pins. The other 2 drivers would be connected to pins 39 and 40 of the MS2 card or to R32 and R36 on the MS V3 board. These resistors could be removed or left in and the MS injector drivers could also be left as is but they would not be functional while using the siamese code in the 4-driver mode. However, they would still be functional (if the resistors are left in) with the normal code and the siamese code in 2-driver modes (no staging or semi-sequential mode). In that case, the p&h board drivers would not be functional (actually 2 will and 2 won't be)."


It says the existing injector drivers "would not be functional in the four driver mode" and I assume from the last sentence about the P&H board ("2 will and 2 wont") that you must be inverting two of the new outputs because of not using the NAND chip for its original function, but does "four driver mode" mean all of the latest version, or only when you set it up for staged ???

Sorry, it's worded even worse now......

Rod.

Edited by Rod S on 22nd Feb, 2009.

Schrödinger's cat - so which one am I ???

It runs !!!!!

Usual problems with ignition setup and the IACV is playing silly buggers.

Idles as smooth as anything.

Just need to move two other minis and get it in the open air so that we can play with the settings without dieing from Carbon monoxide poisionning.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Sorted the IACV. They have changed the logic of the settings so that zero is always fully closed.

We have got the AFRs equal at idle by adjusting the timing values.

Now in for lunch and let the engine cool down before we go for a test drive.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

whos going to be the one that sticks a fork in their cheek hurrying to get out there lol?

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

No hurry.

Engine temp was 95 degrees when we switched off ! Need to find out why the fan is not working.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Sounds like my concerns were unfounded then.....

Let's see some logs !!!

Schrödinger's cat - so which one am I ???

Rod,

As you've seen, the code can work with either the 2 original injector drivers or with 4 additional drivers. And there is no need to invert anything in the code (or in hardware) due to taking the signal before the NAND gate because the signal is inverted again by the MS injector driver.

To have the code use 4 drivers, you simply tell it that you're using additional drivers when you configure things. This is in the sequential menu and is highlighted in red (because you have to power cycle the MS after choosing the option).

I have started making a web page which explains all that but I only have the picture I posted before and added a few modified schematics. There still no text. You can have a look at http://jbperf.com/sequential/index.html.

Jean

http://www.jbperf.com/

Paul,

It's great to see that you have this running already and with corrected AFR at idle. That's great!

Looking forward to more reports. :)

Jean

Edited by jbelanger on 22nd Feb, 2009.

http://www.jbperf.com/

Thanks Jean,

The schematic says what I was expecting, that the two new drivers are taken before the NAND gate and down two socket pins that become free once the old clock chip circuitry is removed, but the original two drivers presumably still go through the NAND gate, even they are not being NAND'd with a PWM signal.

Aknowledging the signal is inverted again by the injector chips, I assumed the first two (that go through the NAND gate) were coming out of the CPU as "1"s and the extra two that don't go through the NAND gate, as "0"s.

I haven't actually seen the new sequential menu highlighted in red because I held off from loading your very new version because of my unfounded worry over the missing hardware.......

I'm afraid I'm just being over-cautious at the moment but you and Paul have both proved me wrong.......

Rod.

Schrödinger's cat - so which one am I ???

Rod,

If you look at the second schematic on the web page, you'll see that the signals going to pins 2 and 5 of the NAND gate are also going to pins 39 and 40 of the MS2 card. This is the signal used for the injectors 1 and 2 when in 4-driver mode. As you can see these don't go through the gate and are therefore not inverted.

In the standard MS injector drivers, pins 39 and 40 control the flyback circuit. However, in 4-driver mode these pins control the new injector drivers 1 and 2. Pins 21 and 22 which are the output of the NAND gate and control the standard driver have an output that correspond to the overlap of injector 1 and 3, and injectors 2 and 4.

Hopefully this will clarify things up and answer your concerns. Moreover, I currently have on my test bench setup 6 LEDs on my JimStim that show the behaviour of the 2 standard drivers and the 4 additional drivers and they all do what they're should do (and not some ligthing up when they should turn off).

Jean

http://www.jbperf.com/

Mixed results so far.

Started by trying to get the AFRs equal purely by timing of the pulses, using the same VE table for both inner and outer cylinders.

Limited results using this method, still inners running richer than the outers particularly at full throttle. This would suggest that there is a significant VE difference as predicted.

Then brought in the dual VE tables to give the inner cylinders less fuel. Not very successful as leaning out the inner cylinder VE table seemed to increase the AFRs for both inner and outer cylinders.

Good at part throttle but we are not sure about full throttle. We found a rogue value in the timing table that would have thrown everything out.

Anyway part throttle log:

Edited by Paul S on 22nd Feb, 2009.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."