To make its inclusion as frozen modules in multiple ports less magic.
Ports are just expected to symlink 2 files into their scripts/modules
subdirs.
Unix port updated to use this and in general follow frozen modules setup
tested and tried on baremetal ports, where there's "scripts" predefined
dir (overridable with FROZEN_DIR make var), and a user just drops Python
files there.
At the WS2812 driver level, a 400ns value was used for T0H (time high to
send a 0 bit) but LED specification says it should be 350ns +- 150ns.
Due to loop overhead the 400ns value could lead to T0H close to 500ns
which is too close from the limit value and gave glitches (bad data to
pixels) in some cases. This patch makes the calculated T0H value 350ns.
Previously they used historical "pyb" affix causing confusion and
inconsistency (there's no "pyb" module in modern ports; but people
took esp8266 port as an example, and "pyb" naming kept proliferating,
while other people complained that source structure is not clear).
This helps to test floating point code on Cortex-M hardware.
As part of this patch the link-time-optimisation was disabled because it
wasn't compatible with software FP support. In particular, the linker
could not find the __aeabi_f2d, __aeabi_d2f etc functions even though they
were provided by lib/libm/math.c.
In both parse.c and qstr.c, an internal chunking allocator tidies up
by calling m_renew to shrink an allocated chunk to the size used, and
assumes that the chunk will not move. However, when MICROPY_ENABLE_GC
is false, m_renew calls the system realloc, which does not guarantee
this behaviour. Environments where realloc may return a different
pointer include:
(1) mbed-os with MBED_HEAP_STATS_ENABLED (which adds a wrapper around
malloc & friends; this is where I was hit by the bug);
(2) valgrind on linux (how I diagnosed it).
The fix is to call m_renew_maybe with allow_move=false.
Size 64 was incorrect and will lead to stack corruption. Size 88 was
verified empirically. Also, allow to skip defining it if MD5_CTX
preprocessor macro is already defined (to avoid header conflict).
ESP8266 SDK2.0 fixes (at least, I can't reproduce it) an infamous bug
with crash during scan. 36K seams to be a safe value based on a download
test (test_dl.py), over 1GB was downloaded. More testing is needed, but
let's have other people participate by committing it now.
There is no automatic reconnect after wlan.active(False);
wlan.active(True). This commit provide the possibility to run
wlan.connect() without parameter, to reconnect to the previously
connected AP.
resolve#2493
It's mandatory function which should be present in every port. Even if
it's not, in the stdlib intro we waarn users that a particular port can
lack anything of described in the docs.
Now the function properly uses ring arithmetic to return signed value
in range (inclusive):
[-MICROPY_PY_UTIME_TICKS_PERIOD/2, MICROPY_PY_UTIME_TICKS_PERIOD/2-1].
That means that function can properly process 2 time values away from
each other within MICROPY_PY_UTIME_TICKS_PERIOD/2 ticks, but away in
both directions. For example, if tick value 'a' predates tick value 'b',
ticks_diff(a, b) will return negative value, and positive value otherwise.
But at positive value of MICROPY_PY_UTIME_TICKS_PERIOD/2-1, the result
of the function will wrap around to negative -MICROPY_PY_UTIME_TICKS_PERIOD/2,
in other words, if a follows b in more than MICROPY_PY_UTIME_TICKS_PERIOD/2 - 1
ticks, the function will "consider" a to actually predate b.
