Request for offset - multiple Master Batteries

[Djeez]

These is an offset for the Master Battery (0x3102) but MSFS2020 supports multiple batteries, such as in the default C172 (standby battery) or SR22 (master battery 2).

When inspecting the log when toggling the switches I see

(0x000102c1), Param= 2 (0x00000002) TOGGLE_MASTER_BATTERY

  (note the parameter 2) 

I could use the ipc.control with parameter 2 in my Lua script but I also need to know the state of the switch. 

The MSFS2020 SDK documentation shows that the

SimVar needs an index so presumably this means that read and write access to all batteries is possible.

My request is to make these settings available as offsets, or one offset with multiple independent bits set for every battery.

Thanks!

-Emile van Gerwen.

[John Dowson]

Hi Emile,

I am reluctant to change the functionality of the existing master battery offset, 0x3102. However, I could add a new bitwise offset that would hold and change the state of the different indexed batteries. However, there is an issue with this. The problem is that if I request the ELECTRICAL MASTER BATTERY simvar for indices > 1 and only one battery is available, this will not produce an error but will flood the MSFS logging console with error messages, making the logging console impossible to use. This was an issue when I recently added offsets for FUELSYSTEM PUMP ACTIVE and FUELSYSTEM PUMP SWITCH for indices up to 16. To get around this, I added a new ini parameter NumberOfPumps that controls how many indices of these simvars are requested. This applies to all aircraft, so it is not an ideal solution, but there is no way that I know of to determine the actual number of pumps available, and for this update there would be no way to know the number of batteries available, and so there is a similar issue.

Not sure what to do about this at the moment - I will have a think about this....

However, there may be an alternative solution. For example, in the C172 there is a lvar XMLVAR_BatterySTBY_SwitchState. You could add this lvar to a free FSUIPC offset (using the lvarst-to-offsets functionality) and read the state of the standby battery from that. If the lvar is writeable, you can then also write to the offset to switch the standby battery on and off. The same or a similar lvar may also be available in the SR22, although I haven't checked this.

I am planning on going through the MSFS documentation on available simvars (and events) this week (hopefully!), to see what new simvars and events are available.
I will consider this request again once I have done this.

Regards,

John

[John Dowson]

10 minutes ago, John Dowson said:

For example, in the C172 there is a lvar XMLVAR_BatterySTBY_SwitchState.

No, sorry I was mistaken. This lvar doesn't exist for those aircraft. It appeared that they did, but that was because I had the FBW A320 installed in my Community folder and I had forgotten top remove this before checking.

John

[Djeez]

Thanks John. Getting errors on non-existent batteries and no way of knowing the number of batteries seems like a bad interface design on MSFS part. I appreciate you looking into this. Did you report this to the SDK team and would it help if I (also) report this?

-Emile.

[John Dowson]

1 hour ago, Djeez said:

Did you report this to the SDK team and would it help if I (also) report this?

Yes I did. It may be a good idea for you also to report this.

John

[Djeez]

What you could do is provide an offset in which I can write in how many batteries I am interested. Since I know which plane is loaded, I set the number of batteries accordingly and it would be my responsibility to set the correct number. The default being 0 so that the bitwise offset is not populated when not requested. This is quite a hack and I can understand you are not fond of such a solution but honestly I don't think we can expect a solution from the SDK team at Asobo in short term.

-Emile.

 

 

[John Dowson]

Possibly. Please leave it with me.

I currently am getting no time for such changes as I am getting too  many support requests, which always take priority over new development...

John
 

[John Dowson]

Hi @Djeez / Emile,

I have now added the functionality to allow the user to add any simvar to a free user offset. I will release this at the weekend, but I have attached a beta below if you would like to test.
To use this, create a file called myOffsets.txt and add the following content:

Quote

// offset, size, simvar, type, units [, w]
0x66C0, 1, ELECTRICAL MASTER BATTERY:2,I32, Bool, w

This will add the simvar  ELECTRICAL MASTER BATTERY:2 to offset 0x66C0 as 1 byte, for both reading and writing. Please change the offset to a free user offset if already using that one.

Cheers,

John

FSUIPC7.exe

[Djeez]

This works great and is a very nice feature to have.

I assume the myOffsets.txt is read during the FSUIPC startup? For development it would be convenient to have a reload myOffsets menu item in the FSUIPC7 interface just as there is one for the WASM reload.

-Emile.

[John Dowson]

1 hour ago, Djeez said:

I assume the myOffsets.txt is read during the FSUIPC startup?

Not exactly - it is read the first time a simconnect connection is established.

1 hour ago, Djeez said:

For development it would be convenient to have a reload myOffsets menu item in the FSUIPC7 interface just as there is one for the WASM reload.

No, that is not going to happen - lots of complications to do that, just not worth it as it only takes a few seconds to restart FSUIPC7 (you don't need to restart MSFS).

John

Edited February 26, 2022 by John Dowson
corrected