millisecond info

[Beerman]

Hi, I'm trying once again to set up a file for the LT1's
I need to know the fmt, op, factor, and offset for milliseconds.
In the sae_generic file it looks like it would fall under UNM-16-41 because seconds are listed there twice.
thanks

[Blacky]

The only reason that you would ever need to have multiple units in the same SLOT is when you want a PID to be able to be displayed in those different units. For example miles/hour and km/hour.
Sometimes I did not follow that advice in the sae_generic.txt file and I placed multiple unrelated units into the same SLOT - it does not really matter. So long as multiple units that you want to have for a single PID are all in the same SLOT.

Usually you would just create a new slot with a sequence number >1000 (EFILive reserves sequence numbers: 1..999 for use in the sae_generic.txt file).

For example, if the millisecond value was a raw 16-bit value (0..65535) divided by 65.535 (a common scaling for ms) then use a slot like this:



*UNM-16-1001
ms 0.0 1.0 .0 / 65.353 0.0


Say you also wanted to offer an "imperial" equivalent, for example "ticks" (if there was such units), and there were 20 ticks per ms, then you would add another unit to that SLOT like this:



*UNM-16-1001
ms 0.0 1.0 .0 / 65.353 0.0
ticks 0.0 20.0 .0 / 3.27675 0.0


Then you can create a PID (say injector base pulse width) that can be displayed in either ms or ticks (depending on the user's selection of Metric or Imperial units) like this:



GM.IBPW FFFF UNM-16-1001 "ms,ticks" Fuel "Injector Pulse Width"

The FFFF would need to be the PID's correct reference number.

Also you would need to have specified which units are metric and which are imperial like this:



*UNITS
#Code System Abbr Description
#----- -------- ----- --------------
ms Metric ms Milliseconds
ticks Imperial ticks Ticks


Make sure if/when you definine new units that they are not already defined in sae_generic.txt. EFILive does not like units being defined multiple times.
Note: The ms units are already defined in sae_gerneric.txt, as None (i.e. not Metric and not Imperial).

Regards
Paul

[Blacky]

And before anyone says "Way too complicated!!!!" I agree. It could have been much simpler.

It was designed in a crazy fit of "let's follow the SAE standard" and define SLOTs as per the SAE specification. And it was extended for other duties as required over the past few years.

The whole PID definition thing (including calcualted PIDs) will probably get redesigned in Version 8.

Regards
Paul