Bench tests needed...

[Ludis Langens]

Shannen Durphey wrote:
> 
> I'd like to add
> about 80 degrees offset to the timing calcs, and it looked like a
> simple matter of adding it in right before the maximum advance check
> is done.
> 
> Ok, is this done in hardware or software?

The problem is in the software.  It computes advance as a 16 bit value,
and then it tosses the upper eight bits when it goes to convert from an
angle to a time interval.

> > Is this something to do with the DIS/dizzy conversion?
> Yes.

Someone ought to look at the differences between real GM DIS and dizzy
applications.  A good choice might be to compare software between the
1227748 and 1228321 ECMs.  The former is DIS, the latter is dizzy I
think.  These ECMs have the same hardware except for the limp home
calibration.  They also use (small) 27128 EPROMs - so the programs can't
be too complex.

-- 
Ludis Langens                               ludis (at) cruzers (dot) com
Mac, Fiero, & engine controller goodies:  http://www.cruzers.com/~ludis/


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