[dan.elliott]

HI.

I have built my board and Tuner Studio works well with, say a simple 60-2 crank and cam with Ardustim, but I cannot figure out how to get the trigger code to work here https://gitlab.com/libreems-suite/ardu-stim/issues/1 . I tried modifying an existing file, but my RPM is all over the place. I think I need to write a new pattern with /* Pointer to friendly name string(ok), pointer to edge array(ok), RPM Scaler(??), Number of edges in the array (144??)*/ in the main but thats where I get stuck

Is there an ardustim updated with the MX5 pattern?

thanks for all your hard work.

NB Do you recommend an Opto Isolator input for my triggers from the car? Was going to build one on proto board and plug into IC3 (will copy the ms schematic)

[dan.elliott]

Ok I have settled on 2.4, 144 for the scaler/ Number of edges and used Josh's updated code in the GIT. Seems to work with STIM matching Tuner studio so I am happy.

Can start adding pots now!

[DanSankey]

my engine uses a 36-2, will i be able to just code this in through tunerstudio?

[noisymime]

my engine uses a 36-2, will i be able to just code this in through tunerstudio?

Provided the 2 missing teeth are beside each other (ie you have 34 teeth, then a 2 tooth gap) then it will work fine with the missing tooth decoder.

If they're in a different configuration though I'll need to know the details of where the missing teeth are.

[DanSankey]

Awesome, thanks. They are together.

[mmonsterski]

I'm using 2cyl engine from Fiat 126p with nanoplex ignition. It using unusual wheel (GMP means TDC):

https://postimg.org/image/3xkinbnel/
I will be very pleased If i could use it as trigger source for speeduino.

[RichCreations]

I'm using 2cyl engine from Fiat 126p with nanoplex ignition. It using unusual wheel (GMP means TDC):

https://postimg.org/image/3xkinbnel/
I will be very pleased If i could use it as trigger source for speeduino.

With such few teeth, it won't give very good resolution.

[mmonsterski]

With such few teeth, it won't give very good resolution.

In my opinion It should be enough. If we measure time between first and second tooth we can estimate angle between second and third tooth.
Using this type of trigger is best for my application, because stock ignition system use it:

[RichCreations]

With such few teeth, it won't give very good resolution.

In my opinion It should be enough. If we measure time between first and second tooth we can estimate angle between second and third tooth.
Using this type of trigger is best for my application, because stock ignition system use it:

I will let Josh (noisymime) answer, but from that I understand, due to the differences in the way stock ignitions work (fire when we see a tooth +/- dwell) vs calculated crank angle that speeduino uses, and the non-constant rotational velocity of the crank, that such few teeth would not provide very good resolution, or accurate timing. Now, if you were keeping the stock ignition, and only using speeduino for fuel, this would not be a problem, but for ignition, you would likely want at least a 12-1 wheel.

[mmonsterski]

I will let Josh (noisymime) answer, but from that I understand, due to the differences in the way stock ignitions work (fire when we see a tooth +/- dwell) vs calculated crank angle that speeduino uses, and the non-constant rotational velocity of the crank, that such few teeth would not provide very good resolution, or accurate timing. Now, if you were keeping the stock ignition, and only using speeduino for fuel, this would not be a problem, but for ignition, you would likely want at least a 12-1 wheel.

In my opinion this should be enough for 2 cyl engine. There is only one ignition for crank rotation and it should be placed between 2 and 3 tooth (there is 80 degree between them).
If we measure time between 1 and 2 tooth we can pretty precise estimate ignition angle where it's necessary.