P4P Clock:tick# jumps and compass error.

[Allen_D]

Hi,

While investigating why the gimbal does not stay aligned with the course in waypoint mode I discovered that the Clock:tick# makes a large jump on almost every flight. I think this could be causing other errors too.

I haven’t received any errors in flight, with one exeption when I received a compass error and it went to ATTI mode.

Can you guys take a look at my DAT files and tell me what you think? FLY130 is the one where I received the error.

https://drive.google.com/drive/folders/1ECqxfw3_7xFtT_NdEOlWGWbg7nv_h9Ar?usp=sharing

Thank you.

[BudWalker]

The short answer is the apparent jump in Clock:tick# isn’t real. It’s an artifact due to the way that DatCon processes the time scale.

Clock:tick# is actually a value computed by DatCon from the IMU_ATTI:atti_cnt:D value. The problem occurs when DatCon encounters a corrupted record and can’t quite figure out how to determine Clock:tick#. I’ve been fine tuning how this works for several versions now.

To see if this is happening I like to compare Clock:tick# against GPS:time

[Allen_D]

Is this something I should be concerned about?

How do I fix it?

[BudWalker]

There isn’t anything you can do except be aware that DatCon can’t present an accurate time axis. It’s not the P4P that has the problem.