Opti spark

[jsmcortina]

I've written an XGATE based wheel decoder for the Opti-spark that uses the hi-res wheel signal and should allow sequential fuel and COP on an optispark equipped engine.

However, I've come to try out the actual optispark I have and I can't get it to put out any signal at all. My first stumbling block is whether I've got it wired the right way around. All the diagrams on the 'net helpfully refers to pins A,B,C,D or the wire colours. That doesn't really help me as I have a bare opti and no pigtail.

Which pin is A ?

If this code works it should be fairly easy to adapt to the other 360 tooth CASes and also possibly the flywheel tooth triggering installs.

James

[turbo355]

Looks like the red/black wire is pin A. This diagram is for a 96 Chevy Camaro 5.7.

[muythaibxr]

He doesn't have any wiring.... so he can't tell which wire is the red/black one. And he doesn't know which end is pin a...

Ken

[turbo355]

Does this help?

[muythaibxr]

We'll have to ask him, but that'll probably work.

Ken

[jsmcortina]

Looks like mine is broken then. I had pins ABCD the right way around but can't get any output on A or B even with a 12V pullup. A is stuck at 0.5V and B at 3.3V.

James

[Joe]

If I recall correctly pins B & C need a 5v pullup-

Joe

[jsmcortina]

I had used the pullup in the tests.

James

[elaw]

This is probably silly to ask, but have you grounded the housing of the unit?

Looking at the schematic you'd intuitively think pin D is connected to power supply negative, but they went to a lot of trouble to label it "reference low"... mabye the actual negative connection is the housing?

[jsmcortina]

The optical module appears to be insulated from the housing.

James

[Joe]

A correction of my above post.

Pin A 5v pullup
Pin b 5v pullup
Pin C 12v Ignition(Straight battery)
Pin D Ground


Joe

[Joe]

James,

If you end up having a bad opti module and cant find one local PM me your address. I think I have one at work I'd be willing to send you.
(I'll check Monday)

Joe-