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
- No longer include `tools/serial.mk` and `tools/avrdude.mk`, as this is
no done by `boards/common/atmega`
- No longer provide `RESET ?=`, as this is now done in `tools/avrdude.mk` for
all ATmega boards unless they are using a bootloader
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supported by RIOT) on outdated versions of avrlibc.
- Use the common logic to translate from a bootloader to concrete flasher flags
- Extended documentation on how to use optiboot as alternative bootloader, as
the stock bootloader is affected by a bug preventing the use of RIOT's
pm_reboot() implementation
- including `avrdude.mk` and `serial.mk` is no longer needed
- the avrdude flag -F is dropped
- This allows flashing a board having an MCU different to the one
RIOT was compiled for
- It is better to let the user provide this flag manually if she/he really
wants to turn safety off, knows what she/he is doing, and accepts the
risk associated with this
- the avrdude flag -D is dropped
- This disables issuing an erase command during flashing, however this
erase cycle is strictly required to be able to program the flash
- This is only needed in case of the stk500v2 bootloader, which implicitly
does the erase cycle and fails if explicitly asked to do so
- Only for the stk500v2 bootloader this flag is now added
- Include `tools/avrdude.mk` and `tools/serial.mk` at the common place instead
for each ATmega based board individually
- Introduce the makefile variable BOOTLOADER to de-duplicate flash configs:
- Two boards using the same bootloader now just use `BOOTLOADER ?= foo`
and share the individual config
- These settings are not applied when `PROGRAMMER` is set to still allow
users to manually specify how to program their board
To quickly iterate on animations it is handy to being able to simulate
the output on native.
This adds a VT100 terminal backend to the ws281x driver that outputs
the colors straight to the terminal.
