DIYEFI.org Forum

Ben, take it away! :-)

There is a listing of current stuff here:

viewtopic.php?p=18346#p18346

What is incomprehensible???

Fred.

"Advance" is a bad name for Ignition Timing. It is way too ambiguous. "Ignition Timing" would be better, assuming it is the actual, final value used to fire the spark plugs.

Maybe something else is appropriate like "Ignition Timing BTDC" or "Ignition Advance" is at least descriptive...
Letting people know in the name that positive is before TDC and negative is after TDC (if we still have negatives?) is important, but so is letting them know that it is the ignition event, and that it is the timing of the ignition event.

I think I like them in this order:
Ignition Timing BTDC
Ign Timing BTDC
Ignition Advance
Ign Advance
Ign Adv


You should even get the units in there...

Ignition Timing (°BTDC)
Ign Timing (°BTDC)
Degrees of Ignition Advance
Ign Advance (Degrees)
Ign Adv (°)

"RPM" should really be "Engine Speed (RPM)"

Good descriptor plus the units in parenthesis or offset somehow maybe with a hyphen.

And in that vane, I guess you could keep going and have:

AAP (kPa)
BasePW (ms)
CHT (°C)
Engine Acceleration (D·RPM)
Engine ???????????? (D²·RPM)
MAP (kPa)
MAP Acceleration (D·kPa)
TPS (%)
TPS Acceleration (D·%)
Dwell (ms)
EffectivePW (ms)
IAT (°C)
MAT (°C)


Some are going to be unit-less.

I agree with most of that.

• IgnitionTiming with a unit of (Degrees BTDC) is good.
• Engine Acceleration is OK, but...
• MAP Acceleration is not, that should be MAP Rate Of Change, or simply Delta MAP
• Engine Acceleration Rate Of Change AKA Delta RPM

Acronyms should be described too.... hmmm.....

Good point re commanded ignition timing vs final. When we have a distinction between those values I'll make sure that it's clear :-)

Any other renaming suggestions that should go into the firmware?

What we can see from above is that we have:

• Field name, used in code, used in textual datalog files, etc, an identifier that is unique and fairly descriptive.
• Display name, for most of the acronyms this could either match the acronym, or be the expanded acronym. I think the acronym should always be part of the display name, though.
• Unit °C, Degrees BTDC, kPa, etc
• Description - what it means or how it's used etc.

How about:

Intake Air Temperature (°C) [IAT]

Thoughts?

Fred.

BenFenner wrote:Some are going to be unit-less.

Then they should have "dimensionless" in the unit display area to be explicit and clear.

OLV and FreeEMS in general isn't something that we should artificially soften excessively, just something to keep in mind.

When you had "D" I thought you were meaning "Derivative". Delta is one way to communicate that, and is probably better. So we can use ΔMAP (ΔkPa) or something like that? Units get the derivative treatment too right?

Fred wrote:How about:

Intake Air Temperature (°C) [IAT]

Thoughts?

If all that can fit where we need it, that is lovely.

I like your delta symbol idea! :-) And yes, units are also delta! :-)

BTW, those vars are not currently in use, but we kind of have that present in the inputTimeTolerance variable... I'll tidy it all up soon enough...