Reason not to use RAW ADC locations? (Dev)
Aug 16, 2010, 08:02 PM
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Reason not to use RAW ADC locations? (Dev)
I'm in the process of trying to find some unused ADC pins on the Evo5/6 ecus.
So I'm logging the 12 ADC memory locations, and I got thinking why not just use these locations instead of the Sub that looks them up and loads one to a memory location.
On the H8s they take 12 uS per channel to process, so 12 x 12 uS = 144 uS.
144 uS vs 1/100 S when looked up in the Main Loop, is a huge improvement for something like Speed Density.
And I think the ADC runs separate from the CPU, so it would use less cycles.
Just thinking out load, I may be missing something obvious?
So I'm logging the 12 ADC memory locations, and I got thinking why not just use these locations instead of the Sub that looks them up and loads one to a memory location.
On the H8s they take 12 uS per channel to process, so 12 x 12 uS = 144 uS.
144 uS vs 1/100 S when looked up in the Main Loop, is a huge improvement for something like Speed Density.
And I think the ADC runs separate from the CPU, so it would use less cycles.
Just thinking out load, I may be missing something obvious?
Aug 17, 2010, 01:37 PM
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if the values change more often than once per main loop, the stuff looked up or calculated, will be based on two ore more different values.
for sd, timing map look up on other load cell than fuel map.
but for logging it might be better to read the adc registers.
for sd, timing map look up on other load cell than fuel map.
but for logging it might be better to read the adc registers.
