Gary Palmer wrote:

Paul,
        Just a nit, but if you know that the staging flag is one, then do the
division for the user, After all divide by two is shift right one bit if using
integer arithmetic.

Good point Gary. Thanks for mentioning that. PL

        I liked the other suggestion on user prioritization of list items. After
all the goal of programming is to make life easier for the end user, not the
programmer; within reason of course.

The big problem with all devices that have a limited user interface, (I.E. few keys
or
switches and a very small number of display pixels) is; they are very tough to
program. For example; programming VCR's, setting the clock in your car,
high end microwave ovens, dryers and washers with too many options, last but not
least
all GPS's and Loran's. Coming up with an easy and simple to learn and remember
programing user interface is next to impossible. If you have a better scheme
I would like to hear about it. People wind up just not doing it.

The ideal would be a PC in the cockpit getting data from Tracy's EFI CPU and other
sources. That is not pratical for a lot of reasons. First and foremost is cost.
Some can afford it most can't. Yes you can build your own cheaply but that takes
some skill. The other major drawback is what if it fails? The third problem is
what if you have an electrical failure? A PC would suck a lot of current. Airliners 
can have this sort of thing as they have backups on the backups and weight of this
amount is not much of a problem. I plan to use as many mechanical gauges monitoring
my engine in my airplane as possible. That way if one fails I am not in dire
straights. The info from the EFI CPU is a bonus so a small LCD is OK. Navigation 
on the other hand will be mostly done by GPS of course. PL

        Programmable limits on key parameters, coupled with an audible alert output
would be great. I would also keep Descriptive strings very short to fit in multiple
parameters per line, maximizing use of display real estate. Stick to a consistent
tabular format for a neat display layout.

        Why the O2 sensor? I thought Tracy chose not to use them due to Leaded fuel
contamination.

Keep reading Gary :-) PL

        Is there a throttle position input to Tracy's controller? If so it would be
a useful additional parameter.

Regards..........Gary

 
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