Suggested 1st Priority

Fri May 6 16:36:32 GMT 1994

Personally I'm not  set on any processor and I am flexible - once I 
understand how all the sensors and actuators work I can always to the 
hardware myself.... so...

Taking someone else requirements list
>So far I've seen:
>1)	The system would have to work at:
>	1.1)	Startup
>	1.2)	Idle
>	1.3)	Part throttle cruise
>	1.4)	WOT
>	1.5)	Deceleration
>2)	It had better be cheap (< $???)
>3)	Ability to talk to the ECM with the engine running.
>4)	Inputs:
>	4.1)	O2 Sensor
>	4.2)	Throttle Position sensor 
>	4.3)	Temperature sensor (temp. of what?)

Water temperature! - to tell when the engine has warmed up enough to lean 
out the mixture a little - perhaps a limp mode to richen the mixture when 
the water temp gets too high.

>	4.4)	Intake air temp. sensor.
>	4.5)	Exhaust temp. sensor.
>	4.6)	RPM sensor (maybe an engine position sensor - so you know
>		exactly which cylinder needs fuel / spark next (distributor
>		mounted of course).
>	4.7)	Either a MAP or MAF sensor.
>	4.8)	Humidity sensor? - or altimeter?

	4.9)	MAT or Manifold Air Temperature
	4.10)   Additional inputs - knock sensors etc.
>I suggest that we add:

should be 5)

>4)	It had better be reliable (> ??? MTBF)

should be 6)...

>5)	The ECM must be small (< 4" X 8" X 2" ??)
>6)	Standardized RS-232c communications interface.
>7)	Outputs:
>	7.1)	Fuel Injector drivers.
>	7.2)	Alarms?
>	7.3)	Timing control?

	8.4)    Additional solenoid and d/a outputs... (Electronically 
		controller waste gate???)

I like it.

Perhaps we could discuss this list?

The come up with a consensus.  Keep the requirements flexible.

A system that can accomodate all the above - and let the end user delete 
things he doesn't want or need.

Next step would be to do research on the sensors and actuators - to see 
what kind of drivers and a/d would be needed.  Those with algorithm 
experience could give input on what kind of accuracy / sample rates are 

Then you can decide what CPU to use - maybe one with built-in drivers maybe 

We may find some people interested in a simple system and some in a more 
complex system.  This might be a good place to split... just keep the info 
on sensors and actuators going.


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