This commit changes the esp8266 boards to use littlefs v2 as the
filesystem, rather than FAT. Since the esp8266 doesn't expose the
filesystem to the PC over USB there's no strong reason to keep it as FAT.
Littlefs is smaller in code size, is more efficient in use of flash to
store data, is resilient over power failure, and using it saves about 4k of
heap RAM, which can now be used for other things.
This is a backwards incompatible change because all existing esp8266 boards
will need to update their filesystem after installing new firmware (eg
backup old files, install firmware, restore files to new filesystem).
As part of this commit the memory layout of the default board (GENERIC) has
changed. It now allocates all 1M of memory-mapped flash to the firmware,
so the filesystem area starts at the 2M point. This is done to allow more
frozen bytecode to be stored in the 1M of memory-mapped flash. This
requires an esp8266 module with 2M or more of flash to work, so a new board
called GENERIC_1M is added which has the old memory-mapping (but still
changed to use littlefs for the filesystem).
In summary there are now 3 esp8266 board definitions:
- GENERIC_512K: for 512k modules, doesn't have a filesystem.
- GENERIC_1M: for 1M modules, 572k for firmware+frozen code, 396k for
filesystem (littlefs).
- GENERIC: for 2M (or greater) modules, 968k for firmware+frozen code,
1M+ for filesystem (littlefs), FAT driver also included in firmware for
use on, eg, external SD cards.
The ability to change the host is a frequently requested feature, so
explicitly document how it can be achieved using the existing code.
See issues #2121, #4385, #4622, #5122, #5536.
Prior to this commit, if the flash filesystem was not formatted then it
would error: "AttributeError: 'FlashBdev' object has no attribute 'mount'".
That is due to it not being able to detect the filesystem on the block
device and just trying to mount the block device directly.
This commit fixes the issue by just catching all exceptions. Also it's not
needed to try the mount if `flashbdev.bdev` is None.
Move webrepl support code from ports/esp8266/modules into extmod/webrepl
(to be alongside extmod/modwebrepl.c), and use frozen manifests to include
it in the build on esp8266 and esp32.
A small modification is made to webrepl.py to make it work on non-ESP
ports, i.e. don't call dupterm_notify if not available.
As mentioned in #4450, `websocket` was experimental with a single intended
user, `webrepl`. Therefore, we'll make this change without a weak
link `websocket` -> `uwebsocket`.
So that the user can explicitly deactivate UART(0) if needed. See
issue #4314.
This introduces some risk to "brick" the device, if the user disables the
REPL without providing an alternative REPL (eg WebREPL), or any way to
reenable it. In such a case the device needs to be erased and
reprogrammed. This seems unavoidable, given the desire to have the option
to use the UART for something other than the REPL.
This patch makes it so that UART(0) can by dynamically attached to and
detached from the REPL by using the uos.dupterm function. Since WebREPL
uses dupterm slot 0 the UART uses dupterm slot 1 (a slot which is newly
introduced by this patch). UART(0) must now be attached manually in
boot.py (or otherwise) and inisetup.py is changed to provide code to do
this. For example, to attach use:
import uos, machine
uart = machine.UART(0, 115200)
uos.dupterm(uart, 1)
and to detach use:
uos.dupterm(None, 1)
When attached, all incoming chars on UART(0) go straight to stdin so
uart.read() will always return None. Use sys.stdin.read() if it's needed
to read characters from the UART(0) while it's also used for the REPL (or
detach, read, then reattach). When detached the UART(0) can be used for
other purposes.
If there are no objects in any of the dupterm slots when the REPL is
started (on hard or soft reset) then UART(0) is automatically attached.
Without this, the only way to recover a board without a REPL would be to
completely erase and reflash (which would install the default boot.py which
attaches the REPL).
Prior to this fix, enabling WebREPL for the first time via webrepl_setup
did not work at all because "boot.py" did not contain any lines with
"webrepl" in them that could be uncommented.
The uos.dupterm() signature and behaviour is updated to reflect the latest
enhancements in the docs. It has minor backwards incompatibility in that
it no longer accepts zero arguments.
The dupterm_rx helper function is moved from esp8266 to extmod and
generalised to support multiple dupterm slots.
A port can specify multiple slots by defining the MICROPY_PY_OS_DUPTERM
config macro to an integer, being the number of slots it wants to have;
0 means to disable the dupterm feature altogether.
The unix and esp8266 ports are updated to work with the new interface and
are otherwise unchanged with respect to functionality.
This is to keep the top-level directory clean, to make it clear what is
core and what is a port, and to allow the repository to grow with new ports
in a sustainable way.
