The iMX RT has a separate wake up controller, the GPC, that replaces
the NVIC when asleep. It adds the ability to only wake up on certain
interrupts. It seems that it requires at least one enabled interrupt
in the NVIC to turn on it's wake up circuitry. It doesn't need to
be the same interrupt as the wake up signal. For example, the RTC
in the SNVS can wake us up if a USB interrupt is enabled. Before
then it won't work. So, we enable the SNVS interrupt on start up
so it can wake us up.
The SPI flash on current Fomu firmware is slow. Circuitpython runs
XIP from SPI flash, and so execution time can also be slow. Ordinarily
this isn't a problem, however certain operations are time-sensitive.
In particular, USB function needs to be handled quickly in order to
prevent the host from re-enumerating the device.
Place several critical TinyUSB structures into RAM, as well as several
hot functions that are frequently called. This reduces execution time
at the expense of system memory, and greatly improves system stability.
Signed-off-by: Sean Cross <sean@xobs.io>
Because CPython 3.8.0 now produces different output:
- basics/parser.py: CPython does not allow '\\\n' as input.
- import/import_override: CPython imports _io.
PEP479 (see https://www.python.org/dev/peps/pep-0479/) prohibited raising
StopIteration from within a generator (it is turned into a RuntimeError).
This behaviour was introduced in Python 3.5 and in 3.7 was made compulsory.
Until uPy implements PEP479, this patch adds .py.exp files for the relevant
tests so they can be run under Python 3.7.
In Python 3.7 the behaviour of repr() of an exception with one argument
changed: it no longer prints a trailing comma in the argument list. See
https://bugs.python.org/issue30399
This patch modifies tests that rely on this behaviour to not rely on it.
And the python34.py test is updated to include a test for this behaviour
with a .exp file.
