Read A: variable by name?

[RoystonS]

Hi there,

I'm just getting started with this library. Is it possible to read an 'A:' variable (e.g. "A:ELECTRICAL MAIN BUS VOLTAGE, volts" directly by name, or must I always use numeric offsets (e.g. 0x2840)?

[John Dowson]

'A' variables are standard simvars and can only be read via offsets.

John

[RoystonS]

Thanks. Ok, so to read those values I need to know both the offset and the datatype (e.g. 8-byte float, 2-byte int)?

Is there any way to look that information up based on, say, an 'A:' simvar name?

 

I'm basically trying to provide a simple way to control the lights on a Honeycomb Bravo. The standard Bravo software supports A: simvar names but not lvars so I was hoping to improve on that. I'm able to read lvars successfully through FSUIPC and the .NET wrapper but using offset+datatype instead of name for 'A:' variables is a bit less user-friendly.

[John Dowson]

11 minutes ago, RoystonS said:

Is there any way to look that information up based on, say, an 'A:' simvar name?

Which FS are you using? If using FSUIPC7. see the offset status spreadsheet - this has the name of the simvar held in each offset, when applicable. I've also attached it. If using other versions of FSUIPC, you can still use this to see which simvar is used, but first check the offset status document for the version of FSUIPC you are using to see if available.

14 minutes ago, RoystonS said:

I'm basically trying to provide a simple way to control the lights on a Honeycomb Bravo. The standard Bravo software supports A: simvar names but not lvars so I was hoping to improve on that.

I thought the standard bravo software to control the bravo lights was via the AFC_Bridge from Aerosoft. There are also a couple of solutions posted in the User Contributions section, although I am not sure of the current status. See the following:

 

 

20 minutes ago, RoystonS said:

I'm able to read lvars successfully through FSUIPC and the .NET wrapper but using offset+datatype instead of name for 'A:' variables is a bit less user-friendly.

Accessing simvars via offsets was the main original purpose of FSUIPC and this method of reading/writing simvars has been around since FSUIPC was originally conceived. The lvar support came later.
The size of the offset is specified in the document and it should also be possible to determine the type, either from the description or by simply logging the values first.

John

 

[RoystonS]

Yes, the AFC_Bridge from Aerosoft works but can _only_ access simvars, so it's not possible to get the master warning/caution lights to work as they're lvar only. It's also very slow, with 1s fixed updates, and its configuration is very clunky. (I've written all the details up here if anybody wants them: https://github.com/RoystonS/honeycomb/blob/main/bravo-lights.md)

I'm on MSFS with FSUIPC7. I'm trying to provide something fairly straightforward for non-developers to use without having to edit LUA code (hence preferring simvars to offset+type+size).  Ok, will check the offset status spreadsheet, and I might have a look at making direct SimConnect calls to read the A: variables.

Thanks!