Strange Issue - Maybe FSUIPC7?

[Tom68]

I think this may be a FSUIPC problem, but I’m not sure. Any ideas on how I can narrow this down will be greatly appreciated.

MSFS 2020 and FSUIPC7,  Saitek Yoke, and 2 throttle quadrants,  Thrustmaster rudder pedals.

2 DIY panels of switches and axes made from an Arduino micro and a Leo Bodnar BU0836A and setup as joysticks.

 

90% of the time everything works fine.  10% certain switches stop working.  The failed ones are all LVARs that I’ve used macros to operate.

When they cease working, while still in the cockpit, I open the FSUIPC window and I can see it recognizes if I actuate the failed switches.  I can also see them in the FSUIPC log while in the failed state.

Windows control panel also shows the switches working.

It happens to all aircraft I try.  However, I’ve only tried 5.

Also note, other switches within the same panel that do not use macros continue to work.  

 

I’ve included a few excerpts from my profile for the A2A Comanche 250 to help see what I’m doing.  Also, I've been thru this with A2A as I first thought it was just the Comanche.

Primer and landing gear both fail.

 

Comanche macro:

5=L:PrimerScrew=SET

6=L:PrimerState=INC ; parameter 2

7=L:PrimerState=SET ; parameter 0

10=L:LandingGearLeverPos=SET

 

Comanche ini

309=PH,20,CM3:6,2   -{Macro 2-Camanche250: L:PrimerState inc}-

310=PH,19,CM3:7,0   -{Macro 2-Camanche250: L:PrimerState set}-

312=PA,30,CM3:10,0  -{Macro 2-Camanche250: L:LandingGearLeverPos set}-

313=UA,30,CM3:10,1  -{Macro 2-Camanche250: L:LandingGearLeverPos set}-

314=PA,24,CM3:10,2  -{Macro 2-Camanche250: L:LandingGearLeverPos set}-

315=UA,24,CM3:10,1  -{Macro 2-Camanche250: L:LandingGearLeverPos set}-

 

Thanks.

 

[John Dowson]

If it is only assignments to lvars (or presets) that stop working, it could be due to a WASM crash. Have you tried exiting FSUIPC7 and restarting it? If not, please try that the next time this occurs. If it still fails and FSUIPC7 fails to load the lvars, then the WASM has probably crashed.

To verify this, you need to exit MSFS and check the FSUIPC_WASM.log file - if the last line does not show that the WASM exited properly with the following message logged:

Quote

Mon Aug 19 09:46:17 2024  [ALWAYS]: <=============================== END OF PROGRAM ===============================>

then the WASM module has crashed. It has been reported that this occurs only when using complex aircraft AND complex scenery,  and is more likely to happen after an aircraft change. The crash seems to be an MSFS issue that I will report. If you find that the WASM is crashing then you can try tuning the WASM via ini parameters to prevent this. You need to disable continual lvar scans by setting
      LvarScanFrequency=0
and if setting this it is also a good idea to tune the delay of the initial scan, by increasing the value of the LvarScanDelay ini parameter (the default is 5 seconds). Suggest, for complex aircraft, you use:
     LvarScanDelay=10

Please see the Advanced User guide on setting WASM ini parameters. You should set these in the FSUIPC_WASM.ini file in your WASM persistence area, not the one in your Community folder. If this doesn't yet exist, copy the one from your Community folder to the WASM persistence are location (details in the Advanced User guide) and then edit/modify.

If the WASM isn't crashing, then something else is stopping the lvars from being updated. Please enable WAPI Debug level logging (Log->WAPI->Debug) and Event logging, as well as WASM Debug level logging (via the FSUIPC_WASM.ini file) and the next time this occurs please exit MSFS and show me/attach both the FSUIPC7.log and FSUIPC_WASM.log files.

[Tom68]

Thanks for your response.  I'll give those ideas a try.

[Tom68]

I don't seem to have the log.   I've got a Steam install.

C:\Users\TomS\AppData\Roaming\Microsoft Flight Simulator\Packages\Community\fsuipc-lvar-module

There is no "work" directory as the user guide says.   Could this be a clue?

I have WASM enbled, I checked that in FSUIPC add on tab.

 

Here's my FSUIPC_WASM.ini file:

[General]
; LogLevel: Disable, Info, Debug, Trace
LogLevel=Info

; LogType: File, Console, Both
LogType=File

; LvarUpdateFrequency: frequency to update internal lvar values list and set in CDA
; Accept values: Off, 6Hz, Second, VisualFrame. If using 'Off', update timer must be active in a client
LvarUpdateFrequency=6Hz

;LvarScanFrequency: the frequency of scans to detect new lvars
;    - positive numbers indicate maximum number of scans per second 
;    - negative numbers indicate minimum number of seconds between scans
;Values for this parameter are constrained to between -30 and +4
;A value of 0 will disable scanning for new lvars
LvarScanFrequency=-2

;LvarScanPeriod: the period (in minutes), starting from aircraft load, when lvar scans will be performed
;Values for this parameter must be positive
LvarScanPeriod=10

;LvarScanDelay: the delay in seconds between when the Ready To Fly stage is reached and the initial scan for lvars is performed
;It is recommended to increase this if using complex aircraft or airliners as it can take a while for some lvars to be created
;for such aircraft.
;Note that lvars created after the initial scan will be found and pushed to clients if the LvarScanFrequency is non-zero.
LvarScanDelay=5

[Tom68]

I found it.  The manual says its in the community folder, but its not.

C:\Users\TomS\AppData\Roaming\Microsoft Flight Simulator\Packages\fsuipc-lvar-module\work

Is the manual in error or is there something wrong with my installation?

[John Dowson]

17 hours ago, Tom68 said:

I found it.

And does it show rhat the WASM terminated correctly or had crashed (when you get the issue)?

17 hours ago, Tom68 said:

The manual says its in the community folder, but its not.

C:\Users\TomS\AppData\Roaming\Microsoft Flight Simulator\Packages\fsuipc-lvar-module\work

Is the manual in error or is there something wrong with my installation?

You are not reading the manual correctly - this is what it says:

Quote

WASM module ini file and parameters

The WASM module takes its default settings from ini files. These are named FSUIPC_WASM.ini and can be located:
    1. In the WASM folder, under your Community/fsuipc-lvar-module folder
    2. In the WASM persistent storage area, which is:
        For Steam installs, in the following folder under your user account:
             AppData\Roaming\Microsoft Flight Simulator\Packages\fsuipc-lvar-module\work
        For MS Store installs, in the following folder under your user account:
             AppData\Local\Packages\Microsoft.FlightSimulator_8wekyb3d8bbwe\LocalState\Packages\fsuipc-lvarmodule\work
      The FSUIPC WASM log file (FSUIPC_WASM.log) can also be found in this location.

i.e. the FSUIPC_WASM.log file can be found in the WASM persistent storage area and not under your Community folder.

John

[Tom68]

OK, the WASM did indeed crash.  I’ve made the changes you suggested.

What are the implications of the scan frequency change?  It seems like it would mean any aircraft type change would require restarting MSFS, true?

For the scan delay, the manual says “the delay in seconds between when the Ready To Fly stage is reached and the initial scan for lvars is performed”.  When does the “initial scan” take place?  When I select the aircraft type, or when I select “fly” from the world map, or when I select “Ready to Fly”?

I ask because the A2A Comanche, when it loads, has a delay after selecting “Ready to Fly”.  You can see that with the tablet of the aircraft open.  There’s a progress bar that takes about 10 seconds to complete.  The A2A explanation is that the sound is loading.

 

So I’m asking is the 10 seconds enough?  Or is this a question for A2A?

 

Finally, I won’t know if this solves the problem for a few days, since this occurrence seems random.  When I feel comfortable that its resolved, I'll reply to this thread just for others in the future who may have the same issue.

Thanks

Tom

 

[John Dowson]

14 minutes ago, Tom68 said:

What are the implications of the scan frequency change?  It seems like it would mean any aircraft type change would require restarting MSFS, true?

No - it will still scan for lvars on an aircraft change. Setting this parameter to 0 will mean that only one scan for lvars will be performed, and after LvarScanDelay seconds after the aircraft is loaded. So, any lvars created after this scan is performed will not be visible to FSUIPC7 for the lvar functionality, although you can still update such lvars via presets/calculator code.

17 minutes ago, Tom68 said:

For the scan delay, the manual says “the delay in seconds between when the Ready To Fly stage is reached and the initial scan for lvars is performed”.  When does the “initial scan” take place?  When I select the aircraft type, or when I select “fly” from the world map, or when I select “Ready to Fly”?

It takes place LvarScanDelay seconds after the aircraft is loaded, i.e. after you press the Ready To Fly button and the camera changes to cockpit.

19 minutes ago, Tom68 said:

I ask because the A2A Comanche, when it loads, has a delay after selecting “Ready to Fly”.  You can see that with the tablet of the aircraft open.  There’s a progress bar that takes about 10 seconds to complete.  The A2A explanation is that the sound is loading.

So I’m asking is the 10 seconds enough?  Or is this a question for A2A?

The LvarScanDelay parameter takes effect after the camera changes to cockpit, do this is probably after the aircraft has fully loaded. You can check all lvars are loaded by performing a manual scan for lvars, using the Add-ons->WASM->Reload menu option. If this discovers more lvars, you may want to consider increasing the LvarScanDelay ini parameter.

Note that some aircraft and utilities seem to continually create lvars. However, it is debatable if such lvars are needed to be known anyway, so they can probably be ignored. And you can always use them via presets/calculator code.

John

[Tom68]

Thanks for the help.

[Tom68]

Just to close the loop for those in the future who may be having the same issue.  I believe John's solution to be correct.  The problem has not re-occurred in about 20 flights.

And I see no ill side effects due to the changes.