The boot order is now:
1. The PX4 bootloader boots, and starts the camera.
2. The camera starts and sends the boot command to the PX4 bootloader.
3. PX4 starts.
This changes the way RC is handled for the Mantis:
- The RC values are re-written when arriving over MAVLink. They are
rescaled from 0..4095 to 1000..2000 and the channel bits added to
separate channels. This makes the downstream handling easier.
- Gimbal pitch is moved from Aux1 to Aux2 as that should be the default.
- Aux3 and Aux4 are used for the photo and video trigger.
- The speed button is used as the FLTMODE channel and set to switch
between POSCTL and ALTCTL.
This adds a check for the previous SYS_AUTOSTART id. If it is still the
old/previous SYS_AUTOSTART id, it will flash the new bootloader as well
as set the proper SYS_AUTOSTART id.
To play a power off tune, I needed to convert the file to C++, so that I
could use the uORB::Publication.
The current implementation starts playing the power off sound but then
stops it as soon as the button is released.
The problem is mostly that we only get an interrupt when the button is
pressed or released but we don't seem to be able to poll it, at least
not in the current state.
This adds the env option PX4_FUZZ which runs the LLVM libFuzzer which
throws random bytes at mavlink_receiver using MAVLink messages over UDP.
The MAVLink messages that are being sent are valid, so the CRC is
calculated but the payload and msgid, etc. are generally garbage, unless
the fuzzing gets a msgid right by chance.
As I understand it, libFuzzer watches the test coverage and will try to
execute as much of the code as possible.
This enables flow control on CDCACM for the NuttX boards which fixes a
problem where HITL would stall.
The stall could happen if the hardware would be a bit too slow in
keeping up with the incoming messages. Often, this happened on arming
because the logger would take some time to log all parameters right at
the beginning.
The stall would then not recover due to NuttX bug where the rx interrupt
would not be restored correctly and instead only a slower watchdog would
release the next read. This watchdog takes 200ms which means it's hard
to impossible to get out of the situation without restarting sim and/or
PX4. For more information about the issue, see:
apache/incubator-nuttx#3633
As a workaround, until that bug is fixed, and because it makes sense
anyway, I propose to enable FLOWCONTROL for the serial via USB.
Julian Oes
Daniel Agar
Beat Küng
Cindy Hsieh
Matthias Grob