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-   MEGAsquirt (https://www.miataturbo.net/megasquirt-18/)
-   -   MS2 AC Idle Up Code (https://www.miataturbo.net/megasquirt-18/ms2-ac-idle-up-code-60882/)

Greg G 10-24-2011 08:39 AM

If it doesn't use sequential, then V3 is fine :)

Braineack 10-24-2011 08:48 AM

it does. I was going to have him load the new firmware once it came out. I set the rev limiter to 5900. :)



positive spin: I loaded it for someone else over the weekend and he's really happy with the function.

Greg G 10-24-2011 08:57 AM

Best function ever :)

Braineack 10-24-2011 09:11 AM

I've been enjoying it for over a year now :)

Greg G 10-24-2011 09:22 AM

Booo :fawk:

Anyway better late than never (wow has there ever been a more appropriate time to use that?) :)

self 10-28-2011 09:19 PM


Originally Posted by Braineack (Post 787183)
it does. I was going to have him load the new firmware once it came out. I set the rev limiter to 5900. :)



positive spin: I loaded it for someone else over the weekend and he's really happy with the function.

I think that would be me. It's kind of weird to hear the compressor engaging and cold air coming out of the vents with absolutely no change in RPM. Really, really nice.

Since the idle droop with the AC, i started paying attention to other (stock) cars and some are better, some are worse but I still yet have to drive a stock car (not necessarily a miata) where the idle is not upset at least a little bit by the ac kicking in.

thanks, brain.

gslender 10-28-2011 09:39 PM

Glad that MegaSquirtSanta's presents are liked by all ;)

The elves and I have been busy working on some new presents and it should be Xmas time again soon.

Cheers
MegaSquirtSanta (aka G)

Greg G 10-29-2011 03:51 AM

Now I'm an elf????



Almost nailed it. Hard to tell when the AC compressor engages (listen for the click of the switch), the fans are more noticeable because the RPMs go *up* a little when they engage! The slight surge on AC disengagement is due to my high D reacting to the idle duty dropping. Will tune that out.

Greg G 10-31-2011 11:42 PM

1 Attachment(s)
Done. Stick a fork in it :)

Version 6c adds the "graceful exit" function, as follows: When AC signal turns off, idle adders turn off immediately, while status 4 jumps to a preset value and counts DOWN at a preset rate. Thus turning off accessories in reverse order (unless you play with hysteresis). Timed right, you will get an RPM drop and turn the AC compressor off just when it drops, so they cancel each other out. Brilliant! :yeah!:

Attachment 186642



Sorry for the quality, I only had my GoPro on hand.

bearda 11-01-2011 01:49 PM

Awesome. How do I get my hands on 6c?

gslender 11-01-2011 05:25 PM

I'm going to release 6c under the MegaSquirtSanta name very shortly (in like a few days)... in fact I'm just putting the gift wrapping on it right now ;-)

sparkstack 11-02-2011 09:58 PM

Seems it's not fully cooked yet. Just loaded it - video showing what happens here:

http://vimeo.com/31523057

gslender 11-02-2011 11:37 PM


Originally Posted by sparkstack (Post 791332)
Seems it's not fully cooked yet. Just loaded it - video showing what happens here:

http://vimeo.com/31523057

Can you elaborate? The video didn't outline what specifically is not working.

Also, what are your Output settings?

G

Greg G 11-03-2011 12:56 AM

AC idle up of 19 is way high! I have mine at 10-11. Plus your idle valve is going way higher than that! What are your settings for min/max duty, and min/max rpm? And your pid settings?

The high AC idle up migh be driving the pid code nuts trying to bring it down to target. I don't know why it opens up even further though.

I think the ve table needs work too. Suggest creating another thread for your issues...with a log and msq. Hard to really see what the issues are from a video.

sparkstack 11-03-2011 07:23 AM

19 works for me and gives me a nice 1980rpm idle while the AC Is on. You can see that midway through the video.

It's plain to see what is happening. Your code adds the initial requested duty, but then inexplicably adds it again. And again. And again. Until status 4 reaches target, by which time my idle valve is at 100%. Once status 4 reaches 120 it drops the idle back down to the initial requested value and it idles at 1980+- 10.

I'll admit I'm still ironing out parts of my tune, but the idle valve settings are set as a result of running the valve test, and my VE table while still needing a little work is not the issue here.

The issue is that your code (or some internal code) keeps adding the AC idle duty setting while ramping up status 4.

Version 5 of your code worked fine. My Pid is not freaking out. It only freaks out when your code tells it to.

bearda 11-03-2011 09:29 AM


Originally Posted by sparkstack (Post 791430)
19 works for me and gives me a nice 1980rpm idle while the AC Is on. You can see that midway through the video.

Why do you want a 1980 RPM idle? Isn't that WAY over your idle rpm target? Maybe the PID is freaking out because you're so far off from where it's trying to be and it hasn't been tuned for those exremes?

Braineack 11-03-2011 09:59 AM

I think he meant 1180 -- so far as I can tell in the video, that's where it rest when he's at 40% DC. But still, that's higher than you really want. 12% adder is the perfect number for a 90-93.


and yes it probably is confusing the code since you're driving the valve up so much and not adding to your target. what are your PID values?

But I've seen this behavior on my MS3 before when I introduced a short into my a/c input. The MS would just keep applying the adder until the idle valve was stuck open.

Greg G 11-03-2011 10:01 AM

I think he may be getting in and out of closed loop and eventually locked out?

I was also thinking of some sort of hardware issue, but wouldn't that reset the status4 count?

It's be much easier to figure out with actual msq and msl files. Otherwise we're just guessing.

sparkstack 11-03-2011 12:45 PM

2 Attachment(s)
MSQ attached.
Also attached is a log from yesterday. Same settings just AC-Idle v5. I'll generate a new log tonight when i get out the office.

Now, to answer the various questions.

1: I'm not going out of closed loop and my PID is not going "crazy" during normal operation. It goes crazy when the AC is engaged with this version of the Mod.

2: Previous version (with the exact same tune and setting of 19.1%) and my car idles perfect with the AC on or off and in closed loop.

3: Watch the video again. Right a the beginning ( i didn't show enough) i'm at 28-29% PWM with an 850+-20 idle. Then the AC kicks in and the PWM goes up to 40% (3 seconds in on the video) which is what i'm calling for.

4: Inexplicably, the code keeps adding 19% every few seconds until status 4 reaches 120. Then after a pause while it tries to get my idle valve to go past 100% it finally allows it to drop down to the initial 40%PWM again - and my car idles at 40% PWM and 1200 rpm. Right where i want it, until the AC kicks in again. Rinse repeat.


Incidentally, why could we not have a version of this mod that removes all the superfluous PID% gains and battery volt droop code and just have a simple system that changes the Idle RPM to a value specified.

For example. If i want a 800rpm idle without ac and the car warmed up vs a 1200rpm idle with the AC on, have it so it just changes between the two in the closed loop idle target table. Sounds like a simpler way of doing it. But i don't program.

bearda 11-03-2011 01:08 PM


Originally Posted by sparkstack (Post 791545)
For example. If i want a 800rpm idle without ac and the car warmed up vs a 1200rpm idle with the AC on, have it so it just changes between the two in the closed loop idle target table. Sounds like a simpler way of doing it. But i don't program.

Because most of us don't want a 1200 rpm idle. We want an 850 RPM idle all the time, if the AC is on or off. The response wouldn't be quite as fast, either. By changing the idle duty you get a pretty quick response, changing the RPM target still means you have to go through the PID control loop, which can't do anything to speed things up by comparison but can dampen the response.


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