Even if boards do not have a clock crystal. In that case, the clock
quality will be very poor.
Always having machine.RTC means that the date/time can be set in a way that
is consistent with other ports.
This commit also removes the special code in modutime.c for devices without
the RTC class.
Signed-off-by: Damien George <damien@micropython.org>
Methods implemented are:
- rtc.init(date)
- rtc.datetime([new_date])
- rtc.calibration(value)
The presence of this class can be controlled by MICROPY_PY_MACHINE_RTC. If
the RTC module is used, the time module uses the RTC as well.
For boards without a 32kHz crystal, using RTC makes no sense, since it will
then use the ULP32K oscillator, which is not precise at all. Therefore, it
will by default only be enabled for boards using a crystal, but can be
enabled in the respective mpconfigboard.h.
Tested with a SD card connected to a SAMD51 board. The SEEED WIO terminal
has a SD-Card reader built-in.
Also a side change to remove a few obsolete lines from Makefile.
Allowing to set a time and retrieve the time. It is based on systick_ms()
with the precision of the MCU clock. Unless that is based on a crystal,
the error seen was about 0.5% at room temperature.
It's no longer needed because this macro is now processed after
preprocessing the source code via cpp (in the qstr extraction stage), which
means unused MP_REGISTER_MODULE's are filtered out by the preprocessor.
Signed-off-by: Damien George <damien@micropython.org>
- Makefile: update to use new ASF4 files, support frozen manifest, and
include source files in upcoming commits
- boards/manifest.py: add files to freeze
- boards/samd51p19a.ld: add linker script for this MCU
- help.c: add custom help text
- main.c: execute _boot.py, boot.py and main.py on start-up
- modules/_boot.py: startup file to freeze
- modutime.c: add gmtime, localtime, mktime, time functions
- mpconfigport.h: enabled more features for sys and io and modules
- mphalport.h: add mp_hal_pin_xxx macros
- mphalport.c: add mp_hal_stdio_poll
