All Flash sans firmware at the beginning and 16K SDK param block at the
end is used for filesystem (and that's calculated depending on the Flash
size).
Most pin I/O can be done just knowing the pin number as a simple
integer, and it's more efficient this way (code size, speed) because it
doesn't require a memory lookup to get the pin id from the pin object.
If the full pin object is needed then it can be easily looked up in the
pin table.
Use the machine.deepsleep() function to enter the sleep mode. Use the
RTC to configure the alarm to wake the device.
Basic use is the following:
import machine
# configure RTC's ALARM0 to wake device from deep sleep
rtc = machine.RTC()
rtc.irq(trigger=rtc.ALARM0, wake=machine.DEEPSLEEP)
# do other things
# ...
# set ALARM0's alarm to wake after 10 seconds
rtc.alarm(rtc.ALARM0, 10000)
# enter deep-sleep state (system is reset upon waking)
machine.deepsleep()
To detect if the system woke from a deep sleep use:
if machine.reset_cause() == machine.DEEPSLEEP_RESET:
print('woke from deep sleep')
Flash size as seen by vendor SDK doesn't depend on real size, but rather on
a particular value in firmware header, as put there by flash tool. That means
it's user responsibility to know what flash size a particular device has, and
specify correct parameters during flashing. That's not end user friendly
however, so we try to make it "flash and play" by detecting real size vs
from-header size mismatch, and correct the header accordingly.
"" is the correct name of the root directory when mounting a device there
(as opposed to "/"). One can now do os.listdir('/') and open('/abc'), as
well as os.listdir() and open('abc').
The config variable MICROPY_MODULE_FROZEN is now made of two separate
parts: MICROPY_MODULE_FROZEN_STR and MICROPY_MODULE_FROZEN_MPY. This
allows to have none, either or both of frozen strings and frozen mpy
files (aka frozen bytecode).
The idea is that if dupterm object can handle exceptions, it will handle
them itself. Otherwise, object state can be compromised and it's better
to terminate dupterm session. For example, disconnected socket will keep
throwing exceptions and dump messages about that.
nlr_pop must be called if no exception was raised.
Also, return value of these callback helpers is made void because ther
is (currently) no use for it.
Main entry point is _boot.py which checks whether FAT FS in flash mountable,
and if so, mounts it. Otherwise, it checks if flash is empty, and if so,
performs initial module setup: makes FAT FS, configures default AP name,
etc. As a last option, if flash is not empty, and could not be mounted,
it means filesystem corruption, and warning message with instructions is
printed in an infinite loop.
Upon start-up, _boot module is executed from frozen files to do early
initialization, e.g. create and mount the flash filesystem. Then
"boot.py" is executed if it exists in the filesystem. Finally, "main.py"
is executed if exists to allow start-on-boot user applications.
This allows a user to make a custom boot file or startup application
without recompiling the firmware, while letting to do early initialization
in Python code.
Based on RFC https://github.com/micropython/micropython/issues/1955.
With .rodata being in FlashROM now, gap can be much smaller now. InstRAM
can be max 32K, and with segment headers, that already makes it more than
32K. Then there's some .data still, and the next Flash page boundary is
0x9000. That figure should be more or less future-proof.
TODO: Refactor makeimg to take FlashROM segment offset from file name.
This was originally used for non-event based REPL processing. Then it
was unused when event-based processing was activated. But now that event
based is disabled, and non-event based is back, there has been new ring
buffer code to process the chars.
Event-driven loop (push-style) is still supported and default (controlled
by MICROPY_REPL_EVENT_DRIVEN setting, as expected).
Dedicated loop worked even without adding ets_loop_iter(), though that
needs to be revisited later.
Before this change, if REPL blocked executing some code, it was possible
to still input new statememts and excuting them, all leading to weird,
and portentially dangerous interaction.
TODO: Current implementation may have issues processing input accumulated
while REPL was blocked.
The idea is following: underlying interrupt-driven or push-style data source
signals that more data is available for dupterm processing via call to
mp_hal_signal_dupterm_input(). This triggers a task which pumps data between
actual dupterm object (which may perform additional processing on data from
low-level data source) and input ring buffer.
But now it's generic ring buffer implemented via ringbuf.h, and is intended
for any type of input, including dupterm's, not just UART. The general
process work like this: an interrupt-driven input source puts data into
input_buf, and then signals new data available via call to
mp_hal_signal_input().
