Suggested 1st Priority
OADDAB at STDVAX.GSFC.NASA.GOV
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.
> 4.1) 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.
> 7.1) 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.
More information about the Diy_efi