Mapping on the Fly

General Megajolt Questions and Answers

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PioneerX
Posts: 1
Joined: Tue Nov 16, 2004 3:16 pm

Mapping on the Fly

Post by PioneerX »

All,

After an unplanned engine change, my car is finally ready to have it's map tweaked. It is possible to change the advance number in a bin with the eninge still running? Will the MJLJ use the new advance?

Thanks

Simon

MartinM
Posts: 433
Joined: Sat Aug 27, 2005 12:08 pm

In general yes - and it's

Post by MartinM »

In general yes - and it's well cool to do so when on a rolling road as you can see the power change straight away ;-)

The only problem I've found is that at higher rpm's (say above 4000rpm), the MJLJ doesn't *always* see the changed map coming across the serial link - when you update the config the whole map goes across, not just the change you've made. I think at the higher rpms, the MJLJ is a bit too busy being an ignition controller to process 150 bytes or so coming across a relatively slow RS232 link.

The solution I found is to just back off the rpm to less than say 2000rpm, update the config, wait 2 seconds then re-increase the rpm

Oliver Sedlacek
Posts: 68
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Location: The Chalfonts
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I certainly do it without

Post by Oliver Sedlacek »

I certainly do it without problems. I haven't noticed any problems above 4000 rpm, and I don't believe the megajolt ever gets really busy even at high rpm. I have found that the megajolt comms are sensitive to spikes, which seems to be more problematic at some rpm.

brentp
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.

Post by brentp »

Yes. The processor and firmware does a good job of load balancing serial i/o and processing of the PIP/SAW pulse.

Brent
Brent Picasso
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PioneerX
Posts: 1
Joined: Tue Nov 16, 2004 3:16 pm

Perfect

Post by PioneerX »

Thanks for all the info guys. Glad to here I can map on the fly. I guess the only improvement I could think of would be to allow the site to be modifed and uploaded from the realtime display. But I guess that would have to wait for a new version of MegaJolt Tune.

I am unfortunatly not a Java programmer so cant make this chnage myself. :o(

Thanks again for the info, it will make my mapping job a lot quicker.

Oliver Sedlacek
Posts: 68
Joined: Mon Sep 13, 2004 8:45 am
Location: The Chalfonts
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I've got a modded version

Post by Oliver Sedlacek »

I've got a modded version which does that but it's a bit experimental and not packaged up. If you're keen to try it I'll try and find some time to sort it out.

Sadly my car is off the road, awaiting new seat belts and an MOT :(

MartinM
Posts: 433
Joined: Sat Aug 27, 2005 12:08 pm

That's strange, I have an

Post by MartinM »

That's strange, I have an alternative (XP only - it's a VB.NET application) configurator in production as well!

It's good enough for me to use on my own MJLJ, but not quite packaged enough to release it - I tried to set it up on a 'clean' PC and it didn't work :-( ... but I'm working on that. Hopefully, the install won't be anything as complex as the Java version.

It is only one window and no tabs - the map, programmable outputs and no. cylinders are all (and always) on the window at the same time and the run time button just highlights the current bin on the map within the same window - so you can do on the fly mapping from the runtime display.

If anyone wants to help me with the install problems, I can send the .exe and the comms .dll (the only two files I think/hope that will be needed) for them to have a go....

brentp
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.

Post by brentp »

Might as well <a href="http://picasso.org/mjlj/?q=node/609">join the party</a>...
Brent Picasso
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