Difference between "Ok-SimC" and "Ok-SimE"?

[Hans Billiet]

I'm again having some "beginners question". Although I succeeded with my first attempt to control the Parking Brake in FSX via FSUIPC, MobiFlight and an Arduino Mega. So making progress!😎

I now start realizing the difference between Offsets and Events (yes, this is step by step...). I was also guided to the document "FSUIPC4 Offsets Status.pdf", which lists all the available offsets. There I found the Parking Brake (offset 0BC8). So start linking MobiFlight info with FSUIPC info.

In my first attempt, I used the FSUIPC offset to connect with both output (LED) and input (button). It worked, but via the MobiFlight forum I learned that I should use an EVENT instead of an Offset to connect to my input (button). I did, and it also worked. Perfect!

If I look at the above mentioned document, I see for the Parking Brake:

• FSRead: Ok-SimC
• FSWrite: Ok-SimE

The explanation of "Ok-SimE" reads "for write only, works okay, but resorting to Sim Events via SimC, not SimVar reads or writes". Hmmmm... being a beginner, I have searched the forum, checked the user manuals and Googled... but didn't find a real good explanation of what that phrase really means.

I always like to make a guess first. Please correct me if I'm wrong.

"Ok-SimE" means that you can write at this offset, but FSUIPC intercepts this and uses an Event instead of controlling that value? Meaning that it "resorts to Sim Events". But still... the complete phrase doesn't make much sense to me.

[John Dowson]

The distinction is technical and is related to the SimConnect API - and not really relevant to users of FSUIPC, so I wouldn't worry about this too much.
SimConnect provides both simulator variables that you can read and sometimes write to (not all variables are writable), as well as 'events' (or controls) that perform specific actions. FSUIPC uses both methods. 

[Hans Billiet]

@John Dowson Ok, maybe I am too "hungry for knowledge"🤓

But can you then just advice me. If I want to use an input (example: button), is it adviced to always use events rather than offsets? I know that in some cases you can use offset as well, but is that info (choice) derivable from your table? Because that is info that I do need to successfuly control the sim.

[John Dowson]

If you want to assign an action to a button, you would use the drop-down 'control' menu to assign the action there. Whether this action is then implemented via an event/control or via updating a simvar is not particularly important. Usually there are various methods of implementing a function. If you had the choice of using an offset or sending a control, then the control method would be preferred - the offset method may use the same control/event in the background, so using the control directly would be (slightly) more efficient.

Note I will be removing those 'Ok-SimC', etc status from the document at some point as I think they are confusing and unnecessary for most users. It would be better to just say if read/write wee working or not (or unknown).