Small space savings, the casting from int to float will bloat
the code a bit. Using wait(1.0f) for example would avoid it,
but seems a bit silly to use floats for anything unless
really needed (in embedded products).
HEAP memory should be 4K aligned for GCC newlib, with ISR stack at the end of
RAM memory we loose 3K of RAM memory. This fix is for device with <16K RAM to
use RAM entirely.
--legacyalign, --no_legacyalign are deprecated from ARMC6 compiler, in order to
remove deprecated flags all linker files should strictly align to 8-byte boundary
Set the ISR stack to be 1KB. https://github.com/ARMmbed/mbed-os/pull/7238
Set the heap size to 3KB(2KB + overhead + spare) so that atleast 2KB free ram is
available for testing.
With dynamic heap size, explicit size is not required. IAR 7.8 supports
static heap, hence the change is needed in IAR linker files.
This fix avoid a long waiting loop in rtc_write function,
which was not acceptable in TICKLESS context.
Implementation comments added.
Global variable name has been updated for easier maintenance:
- LPTICKER_counter is the U32 continuous tick counter
- LPTICKER_RTC_time is the RTC time used to get the time difference
between rtc_read_lp() calls
Need to ensure the transmission has been started before sending a STOP condition.
Issue found on the NUCLEO_H743ZI due certainly to the high-speed clock used.
But this is normally needed also on all STM32 devices using the I2C peripheral version 2.
When both tickless and LPTICKER_DELAY_TICKS are enabled some ST
devices randomly get stuck sleeping forever. This is because the
wake up time passed to the rtc is ignored if the previous match is
about to occur. This causes the device to get stuck in sleep.
This patch prevents matches from getting dropped by the rtc by
deactivating the rtc wake up timer before setting a new value.
Events leading up to this failure for the RTC:
-1st call to lp_ticker_set_interrupt
-delay until ticker interrupt is about to fire
-2nd call to lp_ticker_set_interrupt
-interrupt for 1st call fires and match time for 2nd call is dropped
-LowPowerTickerWrapper gets ticker interrupt but treats it as a
spurious interrupt and drops it since it comes in too early
-device enters sleep without a wakeup source and locks up
Cruz Monrreal
Janne Kiiskila
bcostm
jeromecoutant
Anna Bridge
Deepika
Martin Kojtal
Leon Lindenfelser
Juho Eskeli
Eman869