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Old 01-22-2009, 03:20 AM   #21
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Based on what Joe said in another thread, I think they're both pullups. I honestly don't know enough about electronics to be able to answer the question decisively though. I can tell you that before I developed this circuit, I ran 1K resistors from 5v to each tps output, and measured 0-5v on 1N, and 5-0v on 2L.

I do hope there is a simpler circuit! I've done some embedded programming in the past, but I've never had to deal with anything more than resistors and voltage regulators. It was fun learning to build that circuit, but I have a long ways to go....

The off/half/full is like you said... to tell when throttle is closed, partial, and WOT. I'm running custom code with MAFdot AE (AE based on the rate of change of MAF). Due to how jumpy the MAF signal is, I have to run a fairly high threshold, and consequently AE doesn't work on small changes of the throttle. So, I modified the code so that AE only turns on when the throttle is pressed (partially).

Additionally, I'd like the option of going into open loop when the partial is fully pressed. I'll also have more flexibility when it comes to some of the other features that use the TPS signal, such as idle control, idle advance, overrun, launch control, etc.
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Old 01-22-2009, 06:14 AM   #22
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Would it be easier to dampen the MAF signal? Or, write some delays into the code to smooth out the peaks.
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Old 01-22-2009, 02:27 PM   #23
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The signal isn't linear. At high air flow the changes in rate are very small, and at low air flow they are large. If I were to dampen the signal enough to smooth out the low air flow area, I'd be afraid that it would damage the signal up high.

That said, I am testing out a different MAF circuit that will help to a degree... but the signal will still be noisy.
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Old 01-22-2009, 03:44 PM   #24
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My $0.02. WHY do you need this? What is MS gonna do with this information? Seriously? You can't run TPS based acceleration enrichments with this, and MS looks at MAP (or MAF in your case) to do it's thing. What is gonna change if MS knows it's at idle, not, or WOT?

And you 100% can't sneak a vac line to MS?
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Old 01-22-2009, 04:11 PM   #25
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I'm not sure what you're asking. I answered your questions in my last 2 posts.

In summary: the code is configured so that AE kicks in upon partial throttle application. Additionally, I want to go into open loop on full throttle application.

And no, cheating is not an option.
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