SimConnect_AddToDataDefinition - using RPN to set LVar - SOLVED see last post

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1

The documentation states:

It is possible to get and/or set an RPN “L” variable through SimConnect using the SimConnect_AddToDataDefinition function, for example:

SimConnect_AddToDataDefinition(hSimConnect, DataDefinitionID, “L:VARIABLE_NAME”, “number”, SIMCONNECT_DATATYPE_FLOAT64);

Yet their example just presents what appears to be a default statement. If there’s RPN notation in there, I don’t see it.

I’m trying to set L:XMLVAR_ADF_Mode to a value:
SimConnect_AddToDataDefinition(hSimConnect, DEFINITION_1, “L:XMLVAR_ADF_Mode”, “number”, SIMCONNECT_DATATYPE_FLOAT64);

And I can’t figure it out by reading the “explanations” on the RPN page.

Robert

C++
VS2022

2

The example is just showing the syntax so yours just needs SIMCONNECT_DATATYPE_FLOAT64 replacing with the number you want to set. So it’s LVAR name, data type, value.

3

It seems so simple, and yet.

I tried with 0, “0”.
I tried a int with value 0, a pointer to the int.
Same with float, nothing works.

float NewValue = 3;
SimConnect_AddToDataDefinition(hSimConnect, DEFINITION_1, L:XMLVAR_ADF_Mode, number, &NewValue);

Note this is C++ in VS2022. Running out of ideas…

So I looked at the detailed structure in the SDK and tried a bunch of stuff with all the fields populated:
HRESULT SimConnect_AddToDataDefinition(
HANDLE hSimConnect,
SIMCONNECT_DATA_DEFINITION_ID DefineID,
const char* DatumName,
const char* UnitsName,
SIMCONNECT_DATATYPE DatumType = SIMCONNECT_DATATYPE_FLOAT64,
float fEpsilon = 0,
DWORD DatumID = SIMCONNECT_UNUSED
);

Tried:
hardcode 0, “0”,
int NewValue = 0
dword, and float

SimConnect_AddToDataDefinition(hSimConnect, DEFINITION_1, L:XMLVAR_ADF_Mode, number, SIMCONNECT_DATATYPE_FLOAT64, 0, NewValue);
Also tried passing pointers, still nothing,

AM I MISSING A SUBSEQUENT COMMAND THAT MUST BE USED TO ACTIVATE THE CHANGE?
D’uh, hadn’t thought of that…

I’m using FSUIPC7 in parallel to see if the value changes, nada every time.

Robert
:smiley:

4

I don’t program in raw simconnect so I can’t really help with that but I did notice that your original example had the LVAR inside “” quotes. The later ones you said you tried did not.

5

[quote="Sling380, I don’t program in raw simconnect so I can’t really help with that but I did notice that your original example had the LVAR inside “” quotes. The later ones you said you tried did not.
[/quote]

Nah, it truly wants those quotes. I just tried and it threatened me with unspeakable violence. :smiley:

Same with “number”, it seems to want those too.

Robert

6

Do you use a secondary command to “activate” the change?

7

Nope. It just sends that specific sim event in the one line.No idea if you need something like that when using sim connect directly.

8

Solved here!

https://devsupport.flightsimulator.com/questions/16496/setting-xmlvar-adf-mode-using-addtodatadefinition.html