Previous value was 20 K, now it's 80 K. The older family of these MCUs
(cc13x0, cc26x0) had that size, currently for cc13x2 and cc26x2 it's
80 K.
Signed-off-by: Jean Pierre Dudey <jeandudey@hotmail.com>
From the data sheet:
> **Note:** Only in case when a reset occurs and the POR = 0, the BODR bit
indicates if the V DD(DCDC)(3V3) voltage was below 2.6 V or not.
So the value of BODR is undefined if POR is set.
Clear it to bring it to a defined state.
The function would always return `true` after early boot, so it
is not very useful for applications.
Now it will only (but always) return true when we woke from Deep Sleep
*after* early boot. This makes it behave the same ways as the function
of the same name on SAME54.
Rename the existing function to cpu_backup_ram_is_initialized() to better
match it's semantics.
On the MCB2388 plugging the power will result in both the POR and EXTR
bit being set.
Not sure if this is a property of the board, but it means RTC is also
reset after programming, so it behaves just like Backup RAM.
If we woke from Deep Sleep the POR bit will be cleared, so the RTC is not
reset.
RSIR is 0x1 (POR) if we woke from Deep Sleep.
This makes it hard to distinguish between real power-on and waking from
Deep Sleep, which is why the Backup RAM signature was introduced.
However, calling cpu_woke_from_backup() a second time will always return
true, as the signature will have been set up by early boot then.
Thus, clear the POR bit if the signature was already in place.
The result is:
RSIR == 0 -> woke from sleep
RSIR == 1 -> cold boot
Calling localtime() adds considerable overhead.
There are easier ways to set the date to 1970.
For tests/periph_rtc this results in this ROM change:
master:
text data bss dec hex
31328 240 98064 129632 1fa60
with this patch:
text data bss dec hex
20036 140 98168 118344 1ce48
The reboot process for ATmegas is to enable the watchdog timer and loop until
the wdt reboots this MCU. However, this reboot will keep the wdt configuration,
so that the wdt needs to be disabled during boot. This is done in get_mcusr,
but without the attribute "used" it will be optimized out in LTO builds. This
commits adds the attribute "used" to get_mcusr.
Also simplified the backward compatibility with older ATmegas (currently not
supported by RIOT) on outdated versions of avrlibc.
bitarithm.h is not needed for the interface of shed but may cause conflicts
due to different definitions of SETBIT and CLRBIT
common implementations are: (value, offset) xor (value, mask) bitarithm
implements the later
frac.c and nrf52/usbdev.c use bitarithm.h but where missing the include
sam0/rtt.c defined a bit using mask from bitarithm,
changed that to the soulution used in sam0/rtc.c
