Mazda RX7 stock CAS decoder

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wheeler_express
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Mazda RX7 stock CAS decoder

Post by wheeler_express »

Has a decoder for the stock 24/2 CAS been developed? If not I would like to request one.

Second- does the FreeEms system look for the rising or falling edge of the CAS sensor signal? I have a circuit that takes the +5/-5v signal and cleans it to a falling peak of -5v, or I can reverse the diodes and make it a rising signal. I prefer to leave it this way as I can fire the coils directly from this signal if need be. I can make it a square wave too if that is required.

Kevin Alderman
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Fred
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Re: Mazda RX7 stock CAS decoder

Post by Fred »

Yes, that decoder is easily configurable and in use on several vehicles/engines. It's more generic than that, too, handling any even + 1 combo on crank, cam or per cylinder (rare toyota engines).

With all due respect, if you use such a circuit with a VR signal and FreeEMS on an air plane, I will personally hunt you down and kick you in the nuts for endangering the lives of others and my reputation.

Get a proper conditioner, preferably best in class, IE, MAX992X eg: http://brickems.com/brickrpm/comparison/

Some reading for you:

http://en.wikipedia.org/wiki/Variable_reluctance_sensor

http://www.linkecu.com/support/document ... h-note.pdf

Fred.
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wheeler_express
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Re: Mazda RX7 stock CAS decoder

Post by wheeler_express »

Thanks Fred-

First, you cant hurt my feelings. After owning a 100 employee business for over half my life I dont have any. At any rate, if I were to cry because you thought I did something wrong, it would still be better than crashing after 3 years of building. The circuit that I have is based on one from the only purpose designed aviation EFI that I am aware of.

Feel free to give me any advice you feel I need.

I will look up the chipsets that you sent info on, and keep making progress toward flying this thing.

KA :D
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Fred
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Re: Mazda RX7 stock CAS decoder

Post by Fred »

I wasn't trying to hurt your feelings, only pointing out that I might try to hurt your nuts :-) You're welcome, all the same, though.

MAX992X == best possible current solution, roll with it ;-)

Fred.
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n00bs, do NOT PM or email tech questions! Use the forum!
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wheeler_express
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Re: Mazda RX7 stock CAS decoder

Post by wheeler_express »

Fred, I bought 2 of Jean Belangers' VR boards, and earlier I bought his low impedance injector driver board. As soon as I get some of these other peoples planes out of the way- (it seems that work always gets in the way of the important things :), I will get back to work on the EFI and my own plane.

With the VR board and the injector board, I think I have the hardware to finish putting it together. I will let you know how it progresses.

If you think of any other important hardware, let me know. It takes a long time to get some of these little parts.
KA
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Re: Mazda RX7 stock CAS decoder

Post by Fred »

Cool, no, just a slew of IO filtering and a decent power supply setup. Take a look at what MrOnion is doing here for likely scope of required components: viewtopic.php?p=33767#p33767
DIYEFI.org - where Open Source means Open Source, and Free means Freedom
FreeEMS.org - the open source engine management system
FreeEMS dev diary and its comments thread and my turbo truck!
n00bs, do NOT PM or email tech questions! Use the forum!
The ever growing list of FreeEMS success stories!
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