The existing implementation has about 100ms difference to a reference clock. With the changes this error less than 25us.
- Use sensor_gps messages with hrt timestamps as RTC reference and not the system realtime clock. The PPS interrupt can then be aligned with the GPS clock system.
- Keep fallback based on system RTC when no PPS pulse was captured
- camera_trigger module always publishes the camera_trigger msg (independent of the camera feedback)
- Use camera_trigger msg and set the feedback flag
- Subscribing modules determine if the message is relevant based on the feedback message
When using an FMU channel as PPS capture GPIO, the rtc_edge_time is now set as well. The delay between actual capture and callback is compensated with the elapsed time of the rtc clock.
This PR changes the COM_ARM_MAG_STR parameter to accept values. If the parameter is set to 2, the check is performed and a warning is logged but the vehicle can still arm.
statfs accesses the file-system and can be blocking for an extended period. Since the SD card check is part of the preflight checks in the main thread of commander, it could block its execution and cause various issues. The SD card is only mounted in rcS during boot so the state will not change after the first check.
Michael Schaeuble