Help understanding Optical CAS, NOW WITH COMPOSITE LOG...

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Subaru_EA82_4EAT_AWD
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Re: Help understanding Optical CAS pull-up circuits please..

Post by Subaru_EA82_4EAT_AWD »

jsmcortina wrote:Basic Trigger using the low-res slots only will be fine for a single-coil. However, you can't run sequential fuel that way.

James
Well I am hoping to add coils on plug in the future plus I've heard that the hi-res input ads timing accuracy to the 4 slot wheel even just for basic trigger?
Want a neat way to Check & Set Ignition timing AND CRANK the motor at the same time BY YOURSELF?
A little thing I made up... https://youtu.be/PajlPNF5mmQ
Matt Cramer
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Re: Help understanding Optical CAS pull-up circuits please..

Post by Matt Cramer »

"Basic Trigger" means "Use just one pulse per ignition event", so by definition it could not use the high res slots.

That looks like our 54 mm trigger wheel ought to drop right in.

Image

That could be less effort than making a custom decoder for this engine.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Subaru_EA82_4EAT_AWD
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Re: Help understanding Optical CAS pull-up circuits please..

Post by Subaru_EA82_4EAT_AWD »

Any thoughts jsmcortina?
Want a neat way to Check & Set Ignition timing AND CRANK the motor at the same time BY YOURSELF?
A little thing I made up... https://youtu.be/PajlPNF5mmQ
Subaru_EA82_4EAT_AWD
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Re: Help understanding Optical CAS pull-up circuits please..

Post by Subaru_EA82_4EAT_AWD »

Well I have completed the unit and have done some testing with it piggy-backed to the factory ECU.

I have set the ignition mode to 'log crank and cam' and adjusted the trim pots so the 'teeth' show up in the composite logger and recorded a log.
Image

Here is that .csv log its a .zip because of size but I promise its safe:
ea82T optical cas log.zip
Do you reckon a decoder could be made for this wheel?
Want a neat way to Check & Set Ignition timing AND CRANK the motor at the same time BY YOURSELF?
A little thing I made up... https://youtu.be/PajlPNF5mmQ
billr
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Re: Help understanding Optical CAS, NOW WITH COMPOSITE LOG..

Post by billr »

I didn't open the zip file, but the screen-shot indicates you have the crank and cam signals swapped.
Subaru_EA82_4EAT_AWD
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Re: Help understanding Optical CAS, NOW WITH COMPOSITE LOG..

Post by Subaru_EA82_4EAT_AWD »

Its an optical CAS, low-res on crank (mainboard tach input), hi-res on cam (ms3x cam input).

Isnt that how the Nissan opticals get connected (well cam on pt4 with a decoder)?

Forgive me if not, This is all fairly new to me!
Want a neat way to Check & Set Ignition timing AND CRANK the motor at the same time BY YOURSELF?
A little thing I made up... https://youtu.be/PajlPNF5mmQ
billr
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Re: Help understanding Optical CAS, NOW WITH COMPOSITE LOG..

Post by billr »

Why not swap them anyway, so MS can decode with no need for anything special?
jsmcortina
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Re: Help understanding Optical CAS, NOW WITH COMPOSITE LOG..

Post by jsmcortina »

Unless there's a special decoder, it isn't going to help.

Swapping to the disc that Matt posted is a simple fix.

James
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billr
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Re: Help understanding Optical CAS, NOW WITH COMPOSITE LOG..

Post by billr »

James, just checking to make sure I understand correctly:

The high-res swapped to the crank input would be OK, but the low-res would need to be changed from the that four (unequal?) slot config to something like single-tooth; is that correct?

I think the OP doesn't want to drop-in the DIY wheel because of the desire to still keep the OEM ECU running in parallel.
Subaru_EA82_4EAT_AWD
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Re: Help understanding Optical CAS, NOW WITH COMPOSITE LOG..

Post by Subaru_EA82_4EAT_AWD »

I'm not going to keep the MS3x in parallel permanently, I'm basically doing that at the moment to test it and get some readings.
The reason I dont want to swap the wheels in the dizzy is that my car is my daily driver and I wont be able to complete the MS3x install in one go, so I need to be able to swich them to and fro in the meantime.

I realise I can use 'basic trigger' to run it with basic functionality, but I just thought that it may be an opportunity to add another OE wheel pattern to the library, there are a lot of these subies running around and I bet it would create some hype in the community if there was an 'EA82 optical' option in the firmware.

I most likely cant write the code, but Im willing to perform testing, etc to help.
Want a neat way to Check & Set Ignition timing AND CRANK the motor at the same time BY YOURSELF?
A little thing I made up... https://youtu.be/PajlPNF5mmQ
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