Bench racing ecms Even if ya hate 101 please read

[garfield at pilgrimhouse.com]

On Tue, 16 Jun 1998 00:25:14 -0400, "Bruce Plecan" <nacelp at bright.net>
wrote:

>Well how about a aquarium pump (diapharm type), and a variable
>bleed orifice?..  This connected to the MAP....  Sound better, and then
>OK a real TPS.

Yeah, you're right, I got carried away. You CAN use pots for all the
variables, I s'pose. Except for the frequency modulated sensors.

>The following is a short summary of planned items;
>Initial stuff is comparing how the various ecms think.  ie 32/128/256
>prom series of ecm and how they handle temp corrections.  Then
>MAF to MAP comparisions for a similiar series of engine conditions.
>How much actual difference there is.  Then figuring out what AFR
>in a MAF ecm compare to VE of MAP.  Then being able to have two
>similiar systems to run in back to back tests.  Then be able to verify
>switch/table locations without having to run a car.

OK, OK, slow down, you're runnin circles round me. All I understand is
you wanna "simulate" an engine environment. Sounds right to me.

>my thinking was to eliminate any voltage corrections from the
>list of variables, so the 14.2 was a "must have",  or is this an error.

Geez, I dunno, is there really an adjustment to make if the ALT's not
charging, and the +BAT's only at +12V? NAH, all them sensors are
operating off regulated +5V, so you CAN use something other than an
actual battery. Besides, without the ALT chargin the BAT, the battery
voltage is close to 12V anyway. As long as a power supply can provide
the current you need, might as well use one, instead of that battery.
Lot easier, lighter, safer, less smelly; hey, and if you short most of
the PC supplies out, they drop regulation, fold up their legs, and play
dead till you cycle the power. Much nicer than a real tractor/auto
battery, which normally loves to create fires and explosions if you
short it real good.

>This will go one of two ways,

OK, I gotta coin here somwhere. Hmm.

Nah, this sounds like a good idea. You could get REAL fancy and actually
build a micro that pretends it's an engine to the ECM, just to test the
ECM. Hey, it's a great idea. In the electronics industry, they use
simulators all the time to make sure they've got things right before
they actually build the thing for real. Much better to test ECM
programming mods on the bench first, than on some poor unsuspecting road
rat. B)

Your idea of an engine simulator, at whatever level, is right smack in
the stateOdeArt of electronics. Is that SCARY, or what?

Gar