Because this interrupt is not connected to a GPIO or even the EXTI unit,
but directly to the MCU NVIC, the regular attachInterrupt flow cannot be
used.
Instead, this lets STM32WLx override the setDio1Action() and
clearDio1Action() methods to register the radio IRQ directly. Note that
it would have been nicer to implement this by overriding attachInterrupt
in STM32WLx_Module, but that is never called for virtual pins (because
the STM32Duino digitalPinToInterrupt() macro does not work for virtual
pins).
In addition, because the NVIC is level-sensitive and the code expects
edge-sensitive interrupts (for GPIO, the EXTI module in front of the
NVIC makes the interrupts edge-sensitive), this adds some additional
handling around the user-registered interrupt callback. To prevent the
ISR from triggering over and over again (and also to not require SPI
transactions in the ISR to clear the IRQ flags inside the radio), the
interrupt is disabled in the NVIC whenever it is trigered. Then,
whenever the IRQ flags *are* cleared in the radio, the IRQ is enabled in
the NVIC again. This requires making the SX126x::clearIrqStatus() method
virtual so STM32WLx can override it.
This gives all radios that use an rfswitch (i.e. have
a setRfSwitchPins() wrapper already) a wrapper method for
setRfSwitchTable() too. This wrapper just calls the same method on
Module, to make it easier for sketches to use it.
All radios that support RfSwitch define this method that simply forwards
to the `Module::setRfSwitchPins()` method. Previously, all these methods
duplicated the documentation as well, but this uses the doxygen \copydoc
to remove this duplication.
This:
- Updates syncWord comments after changing it from uint16_t to uint8_t
in commit 55aff74a ([SX126x] Changed pin mapping, added reset,
changed LoRa sync word to 1B).
- Adds missing useRegulatorLDO comments forgoten in commit ea85a663
([SX126x] Pass useRegulatorLDO to SX1262/SX1261/SX1268).
- Makes useRegulatorLDO comments the same in all places (using the more
explicit version).
- Fixes a typo in the doxygen \parma -> \param command.
