EDIS SAW Advance Word Simulator

hjhjr · Post by **hjhjr** » Fri Jun 29, 2007 1:23 pm

I want to build the EDIS SAW Advance Word Simulator. how do I program the mc68hc908qt4 ]micro controller. I want to use it to advance the timing on a generator that runs at 3600 rpm , after the generator is started.

Post by **brentp** » Fri Jun 29, 2007 2:34 pm

Hello,

You must be referring to this writeup: http://www.bgsoflex.com/mjl/mjl_edis_summary.html

There are commerial programmers and circuits for building your own programmer for the QT4 processor. Search for: "hc08 mon08" and "hc08 programmer". That should get you started.

Regards,

MartinM · Post by **MartinM** » Fri Jun 29, 2007 4:09 pm

DELETED: I posted completely irrelevant rubbish

....

Post by **brentp** » Fri Jun 29, 2007 4:37 pm

There may be an easier way to generate the signal- see the VRSSIM project under 3rd party contributions..

http://www.autosportlabs.net/MJLJ_3rd_Party_Software

MartinM · Post by **MartinM** » Fri Jun 29, 2007 5:26 pm

Depends why a SAW simulator is being thought about...

- if you want an EDIS tester to just show a 10BTDC limp home mode is working, then VRSSIM would do

- if you want an EDIS tester to just show a variable timing is working, then you would need VRSSIM and a SAW simulator - I don't think an EDIS does anything if you just send it SAW with no VR sensor signal

- if you want to test a MJLJ/EDIS combination, to show variable timing, then VRSSIM would do

- if you want to test some of the basic MJLJ functionality, then a PIP simulator is all you need - see
http://www.autosportlabs.org/viewtopic.php?t=1259

I'm interested why a SAW simulator is being considered.....

Post by **brentp** » Fri Jun 29, 2007 5:46 pm

Ugh, it was too early for me and I wasn't caffeinated.

I was thinking VRS simulator even though it plainly said SAW simulator.

hjhjr, thanks for updating the original post. Looks like the generator runs constantly at 3600 RPM... You must be referring to this:

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

MartinM · Post by **MartinM** » Fri Jun 29, 2007 5:50 pm

...and I didn't see that the original post had been edited

MartinM · Post by **MartinM** » Fri Jun 29, 2007 5:55 pm

...and in the light of the edit, the best EDIS SAW Advance Word Simulator I can think of is a MJLJ (maybe cut down to the bare minimum number of parts)

Not that I can quite get my head round how the OP is going to arrange the 'ignition advancing' capability...presumably an EDIS is being used somehow....

hjhjr · Post by **hjhjr** » Fri Jun 29, 2007 7:53 pm

I am using the edis ignition system . I want to advance the timing as I posted previously after the generator is started using the EDIS SAW Advance Word Simulator . I would use the start relay voltage to retard the timing through the EDIS SAW Advance Word Simulator. I haven't been able to find a cheap way to flash the mc68hc micro controller.

Post by **brentp** » Fri Jun 29, 2007 8:27 pm

... an idea-

As you know - the EDIS fixes timing at 10 degrees BTDC by default. Apparently you want static timing regardless of engine load or RPM.

if you make your sensor bracket adjustable or the trigger wheel rotate-able you can adjust your timing mechanically.

If you're really clever you might be able to put a screw adjustment on the sensor bracket to adjust your timing back and forth- perhaps extend with a knob at the end of a cable- essentially the same as the knob in the QT4 circuit. It would end up being a simpler design in the end, no?