The new HAL allows to share the timer bit width and frequency,
the actual handling of mapping 16 bits counter up to 32 bits or
64 bits is now managed by mbed common layer.
This makes this ticker layer very similar to 32bits one and much
easier than before.
This commit simplifies ticker interrupt set function and handler.
There were issues around the 16 bits timer wrap-around timing as we were
aligning interrupts with wrap-around limits (0xFFFF) and then reading
TIM_MST->CNT again in timer_update_irq_handler which could lead
to crossing case with the wrap-around (TIM_FLAG_UPDATE) case.
Now we're using the 16 lower bits of the timestamp as the reference from
using in set_compare and never changing it. There is also no need to set
comparator again in timer_update_irq_handler. This is more robust and
also more efficient.
Move to a single more reliable implementation of us_ticker_read()
There were historically 2 versions of us_ticker_read() implementation.
The one removed here was not reliable because us_ticker_read() can be
called in interrupt context which means that TIM_MST->CNT would have
wrapped around while SlaveCounter is not yet updated. So there is a need
to check the TIM_FLAG_UPDATE inside this function, which was not done in
the implementation that is removed here.
- RCC init: unused clock was enabled without any init parameters
- ADC: a parameter setting was missing
- GPIO: mode was not allowed by ST HAL API
- tick: init value was too high for 16b
Laurent MEUNIER
Wilfried Chauveau
bcostm
Jimmy Brisson
Wolfgang Betz
jeromecoutant