FreeEMS firmware feature wishlist! (out of date)

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Fred
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Re: FreeEMS firmware feature wishlist (your suggestions here!)

Post by Fred »

WTDeuce wrote:I wish mine were noise related.... Im not sure they are though as im not using VR sensors :p
I wouldn't be too sure about that being significant. Noise can affect any type of signal, not just VR. Additionally, unless you have "done a dave" then your ms is highly susceptable to noise :-)

Start a thread in non free if you like, but it should be resolvable. My setup with a 36-1 turns 7500rpm just fine on pre-alpha ms2 2.0 code from ages ago. Perhaps scope it.

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Re: FreeEMS firmware feature wishlist (your suggestions here!)

Post by AbeFM »

I second scoping it - as well, I have to agree that a "digital" signal can have noise. Hence the "development" (spelled b-o-r-r-o-w-i-n-g) of the op-amp based circuit for inputs, and it cleared up all my issues.

As to cruise... It doesn't matter, and I would certainly say that if you used EGT based limits, you're going to find at TOP SPEED your 'lean burn' is going to lead to a condition where the car slows down. It is outside the scope of a
performance vehicle" that it's top speed limited by running too lean.

I reiterate that high RPM, high MAT, high TPS conditions are NOT cruise. If I cannot accelerate due SOLELY to the state of tune, the ECU is *failing* in it's job to respond to user input. At 40% throttle, be it 50 mph or 240, I'm ok with the car holding it's speed - but when I mash that throttle (or hold it on the floor) I expect the car to move.
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Re: FreeEMS firmware feature wishlist (your suggestions here!)

Post by WTDeuce »

It took draining my DieHard and a lot of scoping... But I think I finally caught the cause of it. At least I hope its the cause... It seems that my hall sensor is randomly missing a gap, making it a 59-2 wheel. It only happens once in a while so it was a bitch to catch on the scope. Reading the hall spec sheet, it requires a tooth wheel thats 6mm thick. My Electromotive 60-2 wheel is 3mm thick :roll: Im going to buy a second wheel and stack them, as I really want to avoid a VR sensor on the small 60-2 wheel.

Oddly changing to 4 squirts alternating stopped a lot of the idle sync losses, no idea why though.

Once this is sorted, I can finally start tuning hopefully! Thanks for the offers of help thought ;)

THIS is why I think a tooth logger/trigger logger should be an early feature, scopes suck for trying to catch random events like this even at only idle crank speeds.
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Re: FreeEMS firmware feature wishlist (your suggestions here!)

Post by jharvey »

Looks like your hall may be working fairly hard. You've got a fair bit of rounding on the rising edge, but nearly no rounding on the falling edge. That could indicate the wire to the hall is a pinch small for the current it's running, however I'd be willing to bet you already have an over-sized wire. What current do you expect your hall to use when saturated?

If you had resonant, inductive or capacitive issues, I'd expect the falling edge to have similar rounding or ringing, so I don't think you have a problem there. My guess is that the source resistance is running close to the halls current rating, causing a slower on time. Based on the noise shown in your snap shot, I'd say you can safely increase the source resistance backing down the current going through the hall. That would increase the accuracy of the raising edge, as well as make it more sensitive to the those little spikes that seem to get lost from time to time.

Not saturating or not coming close to saturating the hall, may allow you the 3mm sensitivity you are looking for. I'd bet the data sheet's noted 6mm is a maximum limit, and I'd bet you can make it work reliability on 3mm.
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Re: FreeEMS firmware feature wishlist (your suggestions here!)

Post by Fred »

Guys, although this discussion is positive, it's off topic. I suggest starting a new thread in non-free to discuss it. I didn't move the last post because it referred to the tooth logger, and I can't move Jareds as it refers to the one before, and I can't delete them because they are good stuff, but for more stuff on this subject, eg, replying to jareds comment, post a new thread and quote his post in the first post. Other posts have already been removed from this thread for off topic posting, I don't wanna remove more :-)

I'll start thinking about tooth logging now.

Cheers!

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Re: FreeEMS firmware feature wishlist (your suggestions here!)

Post by mrnubs »

Hi,

Is it possible to implement a 3 dimensional mapping feature for the Honda lovers (map vs. rpm vs. cam angle, as opposed to just map vs. rpm). K2xxx series honda engine ECU's contain various maps (in 5 degree increments over, I believe, a 50 ish degree spectrum) to account for variable cam timing. I'm not sure what other manufacturers currently use 3d mapping, but it looks as though other engines/manufacturers might go this way in the future - as the technology is adapted.
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Re: FreeEMS firmware feature wishlist (your suggestions here!)

Post by Fred »

Not without drastically reducing table size, no. There are more ways to skin that cat though, the obvious one is just to not vary the VVT so randomly such that the behaviour is better defined and a single map is enough.

It's just a memory limitation.

I guess you *could* do this, but you would only be able to live tune one layer at a time. There is stacks of flash to store table data in, just not that much RAM.

I hope that helps.

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Re: FreeEMS firmware feature wishlist (your suggestions here!)

Post by AbeFM »

What are you trying to tune? Do you have any well tuned maps (i.e. someone spent the 50 hours of dyno time it would take to fill out a 3D map)? If we could see a 3-D map, I'd like to look at it, and see if it's a capability, or a feature - i.e. you could store what's essentially a 3rd independant variable (i.e. 10% more fuel per 2 degrees of cam timing) in a 3rd dimension, but it's not doing anything.

I could even envision a 1 dimensional table (or two, for MAP vs ANGLE) to give you a timing or fuel modifier, which would store nicely, and that multiplied by the main table gives you your output. This would not be so bad, memory or speed wise.

I have some interest, too, as I'm putting VVT on my engine this week.
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Re: FreeEMS firmware feature wishlist (your suggestions here

Post by jonr »

Is "watchdog timer" in there somewhere?
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Re: FreeEMS firmware feature wishlist (your suggestions here

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