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Old 04-10-2008, 07:34 PM   #10 (permalink)
EcoModding Apprentice
Join Date: Dec 2007
Location: Ventura, Ca
Posts: 112

Whoop's Wheels - '89 Honda Civic Wagovan
90 day: 39.09 mpg (US)
Thanks: 1
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Ok, I've got a couple of thought's, for consideration.

In thinking about it, if we are only looking to update the display or send out the serial data, once per second, then the code and hardware don't really need to sample either the speed, injector on time or frequency any more quickly. Consequently, the code could reasonably sample the speed for 10 cycles, average that and store it. The same thing is true for the injector on time and frequency. Statistically this would give us some pretty highly reliable intervals for calculation and display. It should also make the code pretty straight forward.

One request was for RPM to be displayed. In thinking about the above, the RPM can be inferred, largely, from the frequency of the injector pulse. The exception to this would be if the injector is not turned on, as it is not when my rpm is above about 1200 and I have my foot off of the throttle.

Third, one of the things I would like to have is the ability to see if my speed is going up or down and whether my fuel mileage is going up, or down.

On the display, it may turn out that we have to not update the screen, to frequently, as at some rate of change it may become jibberish.

Although I ordered my freeduino a week ago, I still haven't received it.
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