ADS-B Squawk Codes are Always Zero

[nichogenius]

Issue details

Squawk Codes from ADS-B always show as 0.

I am receiving ADS-B data in SBS-1 format from a dump1090 receiver. This is essentially a type of CSV. Not every message will have the current squawk code of the aircraft and the squawk field will be left empty. Mission Planner is interpretting an empty field as a squawk code of "0".

Ideally it should remember the most recent non-null value and time out the value after a period of time such as 30 seconds.

A null squawk is different than a squawk code of zero.

Version

1.3.81 (build 1.3.8741.25556)

Platform

[ ] All [ ] AntennaTracker [ ] Copter [ ] Plane [ ] Rover [ ] Sub

Airframe type

What type of airframe (flying wing, glider, hex, Y6, octa etc)

Hardware type

What autopilot hardware was used? (pixhawk, pixracer, PX4FMU etc)

Logs

Please provide a link to any relevant logs that show the issue

[MUSTARDTIGERFPV]

#3251 fixes this