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speed of the ECU aren't dependent on one another. The general rule is that you need to make sure that your sampling rate of a sensor is > twice the required rate of acquiring usable information. For example, the CAS. There is a slit for every degree in the disc. At 7000RPM, that thing is spinning at 3500RPM. 3500 * 360 = 1,260,000 data points per minute. 1,260,000 / 60 = 21,000 data points per second. So, 21,000 * 2 - 42,000Hz (42 KHz)sampling rate minimum to monitor that sensor successfully at 7000RPM. The thing is, the A-D converters in the ECU run several times faster than this. At 3MHz clockspeed, the ECU sees the engine in every degree of rotation and is capable of calculating instantaneous fuel delivery, timing, IACV control, everything, for every angle of engine rotation. Its as if you were to sit there with a calculator and do the math all yourself for every degree. Imagine calculating those control parameters 360 times? That's two full rotations of the crank. You'd be at it for days. :) The ECU does this 42,000 times per second. A 16MHz processor will certainly open up the potential for more elaborate coding. Whether that is necessary or not would probably be a better question.. :-)
[ ashleypowers.com ]
[ agpowers@bellsouth.net ] When pigs dance, you better get it on video... "You never really learn to swear until you learn to drive."
-George Carlin
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