> snips...
> > Well then as I understand it these GM LS1
> one-coil-per-plug
> units do not have a problem with charging time and
> current
> limiting. They fire when they are told  with a
five
> volt
> pulse and thats it. I could be wrong. These are
the
> units most
> of us have and most of us are using now. GM part #
> 12558948
> If it takes some signal conditioning so be it.
> If necessary I can set one up on the bench as I
have
> a
> pulse generator and 12 volt power supply with
> current
> monitoring to verify.
> > Lets keep this simple and deal with only one issue
> at
> a time. Too confusing otherwise. I am not
> considering
> the extra code at this time. Just the basic
>   MEGASQUIRT- 2001- V3.000 code to keep it simple.

That's a good place to start, but you will not be
able
to control ignition with the V3.000 code.  If you
plan
to work out another solution on that front, then
this
code will work for fuel only.  The only other issue
that comes to mind would be injector staging, which
again is offered only in the -extra code.

> For example: I assume the RX8 wheel will be
> incorporated
> in the extra code so that is of no interest right
> now.
> Is that a correct statement?

Yes...certainly will not be ported back to V3.00.

> We can make a cheap steel disk that will work with
> 2nd gen,
> third gen or RX8 keeping it simple.
> > Some of us would also like to use MSD units. As I
> understand
> it these too can be fired with a simple five volt
> pulse.
> > Paul Lamar ...No rotor no motor.

If you want to run LS1 coil packs from -extra code,
then it's pretty straightforward.  Like you say,
these
units have integral ignitors and take a logic-level
signal, so driving them should be simple.

In the msnsextra code settings for rotary, there is
an
option for FC or FD style ignition triggering.  You
want FD.  Here's the difference:

FC uses a single trigger pulse for leading.  The
trailing uses a trigger pulse at the same frequency
as
the leading, but some ecu-determined timing offset.
As the two trailings need to fire separately, there
is
a third signal, the 'select' signal, which
determines
which of the two individual trailing coils to fire.
So...three control signals to the coil packs -
leading
signal, trailing signal, and trailing select signal.

FD uses a single trigger pulse for leading as well.
For trailing, each coilpack has it's own dedicated
timing signal, rather than the 'select' method used
in
FC.

The rotary code is set up to use the three led
circuits as ignition outputs.  Pullup resistors need
to be added  as shown in the pic part way down this
page:

http://megasquirt.sourceforge.net/extra/setup-gmdis.html

The two leading coilpacks would be fired together
via
one led driver circuit, and the remaining two led's
would fire the two trailing coils.

I realize the MS world is hard to follow.  Such is
the
nature of a highly active open source community.
Development happens at lightning speed, so newer
codes
are feature rich, but often documentation-poor!

Roger.

You are back to talking extra code here. I am not
going
to run the extra code. If necessary I can modify the
basic
V3 code. There is a lot of stuff in the extra code
we don't need for an aircraft application.
I don't really care about new developments anyway.
They mostly seem to deal with car issues.
Extra code is four or five times larger. Harder
to maintain, harder to debug and harder to modify.
Keep it small and tight. KISS

Paul,

Why bother modifying the V3 code, when the work is
already done?  The majority of the code bloat that
occurs in -extra results in increased program size,
but not proportional increase in cpu overhead.  Big
blocks of code are jumped over each cycle if that
particular option is not enabled.  If you want to hack
a code base, go to -extra, and pull out the code
blocks you don't need.  You could drop in size
dramatically, but as there's no issue with flash
storage space, trying to reduce program size would
have little tangible benefit.

The extra code as it sits will fire the LS1 coils with
only the addition of pull-up resistors to the board.
The extra code will also decode a variety of different
wheel configurations, so that side is also addressed.
Seems like a logical choice to me, unless you are
looking for another project.

Roger.

I'll take a look at that idea Roger. Thanks.

Paul Lamar ...No rotor no motor.

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