Hallo,
After several similar issues reported FSX/FSUIPC4 I m facing the same in P3D v4. Communication between MASTER and CLIENT (IVAP 2.0.2) use Offset $7B91 for change Ivap squawk box from STNBY to MODE C which is not working. Other offsets are linked and functional, so I guess there is no issue with firewall or any data flow restrictions
Reading several articles tried to implemented fixes in FSUIPC.ini like NoActionOn7B91=Yes. Unfortunately still without success.
Installed / FSUIPC5 5.14, WideFs 7.15, P3D v4.4
Hardware in cockpit / ATC Transporder by Opencockpit, SIOC 6
After 2 weeks of investigation I m in the end of ideas. No problem occurs in FSX and FSUIPC used several years before my change to P3D...
Thank you very much for the direction and any support
Best regards, Roman
*** Moved to main support forum ***