PX4/Firmware — pull request #1079 by LorenzMeier (2014-06-26 11:00:51+00:00)
Title: Heartbeat sending enforce

I found a rare condition where the status topics wouldn't update together in HIL, leading to the system not sending constantly heartbeats. This patch

- Enforces a minimum rate configuration of 1 Hz
- Always sends a heartbeat, independent if the topics updated

Inter-system (onboard) links also should send heartbeats, so special link modes still work as specced.