Software questions

74_351c · Post by **74_351c** » Sat Mar 06, 2004 1:26 am

I was just wondering how mjlj calculates the advance above the max rpm in the lookup table, as well as below the min value in the lookup table? Does it just continue using the min/max table value?

Also, what is the best way to set inital (idle) timing?

Post by **brentp** » Sat Mar 06, 2004 3:57 pm

With the MJLJ it just continues using the max/min value.

For idle timing, you would probably set using the traditional process of setting timing with a mechanical distributor, but just using the software to adjust the idle. I presume that one would "box in" the idle region with the specific idle advance they chose.

Luca Lagonigro · Post by **Luca Lagonigro** » Mon Mar 08, 2004 10:34 pm

I found that if the RPM value drops below 450, the advance used will be the maximum at courrent MAP pressure.

Below 450 RPM the runtime display jumps to 2147483647 RPM, software uses the highest RPM advance possible. I can see from the Oscope that the SAW pulse is "advanced" (shorter pulsewith).

If true this can cause some problem when cranking up the engine.

Brent when you'll fix that 2147483647RPM bug?

Luca Lagonigro · Post by **Luca Lagonigro** » Mon Mar 08, 2004 11:00 pm

Further testing: outputs are affected as well...

Post by **brentp** » Wed Mar 10, 2004 1:12 am

I never noticed a problem with cranking. However, this is a problem that needs to be fixed.

Expect to see a new firmware version in the near future.

Luca,

Could you try programming the KX8 bootloader and using that to program the MJLJ firmware? I had no problems programming 50+ processors with the bootloader, I would just like to see your feedback on how it works.

Thanks,
Brent

Luca Lagonigro · Post by **Luca Lagonigro** » Thu Mar 11, 2004 12:02 am

I've tried right now the bootloader procedure a couple of time back and forth between different mjlj.s19 it works flawlessly. I tought it was more difficoult than remove and program the KX8 on the Willette, I was wrong, in circuit programming is the way to go for firmware updates. Good work Brent (as usual)!!!

Brent did you have something attached to the programmed outputs? I cant seem to get anything out of mine. I've 5V - 0V at the KX8 PGM pins to the 1K resistors everithing looks good but nothing happens after the 2N2222s. How can I've screwed up all the programmable outputs? 2 things come o my mid diodes or transistors, they're all oriented the same way everithig works or nothing works... Voltages are there but I probably messed something as usual.

I'm too tired... now I seriously need some sleep... (1.00 a.m. here)

Cheers

Luca

Luca Lagonigro · Post by **Luca Lagonigro** » Thu Mar 11, 2004 8:21 pm

Yes I was tired: the outputs are fine I was looking for 12V output but finally I looked in to the scheme and I discovered GND...

The HIGH/LOW setting in the mjljt fouled me, I guessed 12V/GND in fact is GND/OpenCircuit.

Luca

vw16vt · Post by **vw16vt** » Fri Mar 19, 2004 2:06 am

Hi Brent,
I can confirm the 2147483647 when I'm just plugged in without any inputs, but the advance stays at 0, even if I play with the map it doesn't move the highlighted value. When it willl be on the car will be able to check real life and not only bench simulation.

Math

Post by **brentp** » Fri Mar 19, 2004 3:53 pm

I don't know how you have your car set up now- if it's already running with a distributor or not...

The best thing to do is to first get the engine running only with the EDIS module- without the MJLJ controlling it. This will run the engine at 10 degrees BTDC.

if you're running the megasquirt you would feed it's tach input with the PIP signal from the EDIS module.

Once you verified everything is running ok, you can wire in the MJLJ.

Connect the power;
Connect the EDIS PIP output to the MJLJ PIP input;
Connect SAW output on the MJLJ to the SAW input on the EDIS module;
Connect the Tach output from the MJLJ to the tach input on the Megasquirt

The engine should fire up, and you should see activity on the runtime screen. Use a timing light to monitor changes in timing- either through RPM changes or by changing the config while the engine is running.

Brent

Luca Lagonigro · Post by **Luca Lagonigro** » Fri Mar 19, 2004 4:16 pm

One question:

why take the TACH_OUT from the MJLJ SAW_OUTPUT?

Wouldnt it be better to generate it from the PIP_OUTPUT from the EDIS in any case?

I'm asking this because in case you have a Mega Squirt and the MJLJ fails... the EDIS module will fire the coils at 10deg BTDC but MS will mot receive the TACH signal from the MJLJ... EDIS Limp Home mode will be useless as MS will not detect TACH activity.

Wadda you think?

....................................

p.s. I was sure EDIS Module had a TACH_OUT itself, after some google search:

http://www.dainst.com/info/edis/edis.html

http://www.bgsoflex.com/mjl/mjl_edis_summary.html

I found that "maybe" EDIS 4 at pin 11 has a TACH_OUT signal (I'll Oscope it tonight), but not on EDIS 6 and 8.

If you look at the EDIS 8 connector in this page
http://picasso.org/mjlj/?q=node/view/2
you'll see that there are 14 wires out of a 12 pin connetor.

Something is not 100% clear, anyone with a EDIS 6 or 8 can confirm it has a 12 pin connector?

Post by **brentp** » Fri Mar 19, 2004 8:50 pm

when I originally designed it I tried tapping the TACH_OUT from the PIP pin, but it seemed like the EDIS module could not sink enough current to handle both. So I added it to the SAW output.

In an emergency, one could connect the EDIS PIP to the to the megasquirt tach input. You'll be certain to know that the MJLJ is working correctly!

if you're talking about the EDIS IDM signal, it's not appropriate for the tach out because it generates a periodic "diagnostic" pulse when the engine is not running. This will cause the injectors to fire, eventually flooding your engine.

Brent

Luca Lagonigro · Post by **Luca Lagonigro** » Fri Mar 19, 2004 11:07 pm

>if you're talking about the EDIS IDM signal

No, IDM signal is at pin 2 of all EDIS modules, look at the picture here: http://picasso.org/mjlj/?q=node/view/2 there is a "TO TACHOMETER" wire... however...

I've just finished my MJLJ+EDIS benchtesting, everything works OK!!!

vw16vt · Post by **vw16vt** » Sat Mar 20, 2004 1:54 am

I can confirm that EDIS 8 module has exact same connector so the pin 14 just doesn't exist! It's the same exact connector as my EDIS 4 module.

Math

Post by **brentp** » Mon Mar 22, 2004 9:14 pm

great- how is your bench test setup? did you run a wheel on a motor like what I did here?

<img src="http://picasso.org/mjlj/images/EDIS_testBench.jpg"/>

Luca Lagonigro · Post by **Luca Lagonigro** » Mon Mar 22, 2004 9:54 pm

No... well I made it different;)

I've just uploaded here my 36-1 how to: http://autos.groups.yahoo.com/group/meg ... al%20.wav/

Have a look at it and try it if you can, that's really easy to make. If you find it useful feel free to turn my bad english in to something more comprensible.

Dont lough ok?

Luca

Autosport Labs

Software questions

Software questions

With the MJLJ it just continu

I found that if the RPM value

Further testing: outputs are

I never noticed a problem wit

Bootloader

Yes I was tired: the outputs

2147483647 rpm

I don't know how you have you

One question:why take the

when I originally designed it

>if you're talking about the

EDIS 8 is 12pins

great- how is your bench test

No... well I made it differen