Let the variable have a random name since we are not going to reference
it. This allows more than one WITH_SEMAPHORE() per context and also to
avoid shadowing if we open inner contexts.
We don't need the specialized one inside WithSemaphore, so use the
abstract one which allows us to more easily convert between current API
and the HAL_Semaphore one.
While at it also remove additional pragma and allow constructor to
receive a pointer for convenience (we will just dereference it).
See discussion here:
https://github.com/ArduPilot/ardupilot/issues/7331
we were getting some uninitialised variables. While it only showed up in
AP_SbusOut, it means we can't be sure it won't happen on other objects,
so safest to remove the approach
Thanks to assistance from Lucas, Peter and Francisco
It uses a heating resistor controlled by a pwm.
By changing the duty cycle of the pwm, we can control the temperature.
A simple PI algorithm is used in order to get to the correct temperature
fast enough and without too much overshoot
It is implemented as a member of the Util class in order not to make to much
modification to the current codebase