[Solved] PMDG 737 MSFS 2024 – FMC Origin/Destination uitlezen via FSUIPC7 offsets

Posted by: @mente

↑

Can you confirm whether these offsets are correct and supported in FSUIPC7 for the PMDG 737 MSFS 2024?

• Origin: 0x65C0, 5-byte ASCII string
• Destination: 0x65C5, 5-byte ASCII string

Why do you think this information is held in those offsets? Please see the included documentation (Offset Mapping for PMDG 737) for a description of the data held in the PMDG offsets. 0x65C0 holds ' MCP_Course[2] ' and 0x65C5 is within the offset are that holds ' MCP_IASMach' which starts at 0x65C4.

Posted by: @mente

↑

If not, which exact FSUIPC offsets or PMDG SDK fields should be read for FMC origin and destination?

There don't seem to be any fields that hold this information - again, see the documentation for the available data/fields. For the destination, you could try offset 0x6137 which holds ' GPS: Flight plan destination airport ID'.

The CDU data can be read from the CDU offset area - again, see the documentation.

Thank you for clarifying the offsets. The information I had received about 0x65C0 and 0x65C5 was incorrect.

Following your suggestion, we have now tested reading the CDU screen data.

My setup is MSFS 2024, PMDG 737-700 and FSUIPC7 version 7.5.9. Normal PMDG system data is being received correctly.

The aircraft’s 737_Options.ini contains:

[SDK]
EnableDataBroadcast=1
EnableCDUBroadcast.0=1
EnableCDUBroadcast.1=1

These settings were saved with the simulator closed. After restarting MSFS, we confirmed that the settings were still present.

With the left CDU displaying RTE 1 page 1, showing ORIGIN EHGG and DEST EHAM, we restarted FSUIPC7 and ran a short read-only Lua test.

The script reads the documented CDU areas at 0x5400 and 0x5800, using the column-first layout of 24 columns × 14 rows, with three bytes per cell. Across six samples, both screens returned blank text and Powered=0.

The FSUIPC log confirms that the test started and completed without a reported read error. I have attached the script, its output and the FSUIPC log.

Is there an additional setting required for CDU screen data with this aircraft in MSFS 2024, or could you advise how to diagnose why these areas remain empty?

The intended use is only to read ORIGIN and DEST when the RTE page is displayed, without sending any CDU button commands.

The test output contains six samples. In every sample, both CDUs show Powered=0 and all 14 rows are blank. The forum does not allow me to attach the .txt output file.

Kind regards,
Mente

I don't have the 737 for MSFS2024, but I checked your script using the 777 in MSFS2024, and it seems to work as expected - see the attached output:

I will check the 737 in MSFS2020 later - should be the same as for MSFS2024 as the code is the same.

Can you double-check that broadcasts are really enabled. It looks like the specific PMDG offsets documents have not been updated for MSFS2024, so the locations for the 737_Options.ini file are incorrect. For a Steam installation, the location of this file is 

 [User]/AppData/Roaming/Microsoft Flight Simulator 2024\WASM\MSFS2024\pmdg-aircraft-737\work

For MS Store installations, it should be under:

 [User]\AppData\Local\Packages\Microsoft.Limitless_8wekyb3d8bbwe\LocalState\WASM\MSFS2024\pmdg-aircraft-737\work

Posted by: @mente

↑

The forum does not allow me to attach the .txt output file.

You should be able to attach *.txt files - see mine above!

I will now test your script using the PMDG 737 but in MSFS2020....

You can also add

    TestOptions=x400

to the [General] section of your FSUIPC7.ini - this should then log the first data package received from the aircraft, which would confirm that the data broadcasts are being received.

Looks good here in the 737 in MSFS2020 as well:

Also, from the log file you attached, you seem to have started the lua script only 9 seconds after FSUIPC was started. This was probably before any PMDG data had been received - you need to wait a while longer for FSUIPC to initialise and request the data, I would recommend running the lua script on a button or key press while you are developing/testing this, and run it after everything has loaded and settled down, at lease a minute after starting FSUIPC manually.

Your log indicates that you have not installed the FSUIPC WASM module. That maybe ok if you do not use it, but means you have no access to lvars, hvars, presets, etc... If this is on purpose then this is ok, but if this is an installation issue then this should be rectified - you can show me / attach your InstallFSUIPC7.log if you did not opt to not install the WASM.

Regards,

John