The idea is that these tests can be run with just a test server running
on a test host, with device under test connecting to it, instead of
requiring Internet connection for testing.
Such setup is however WIP, and some tests in net_hosted/ are so far
written to connect to Internet, as there're not test server written
yet. This is expected to evolve over time.
GC finalization should be enabled for modlwip, or it may lead to GC
problems with socket objects. This decreases usable heap size from
36288 to 35968 (-320) bytes.
It belongs with the other pin config functions in machine_pin.c. Also,
esp_mphal.c is put in iRAM so this change saves about 300 bytes of iRAM
(and mp_hal_pin_open_drain is not a time critical function so doesn't
need to be in iRAM).
These drivers can now be used by any port (so long as that port has the
_onewire driver from extmod/modonewire.c).
These drivers replace the existing 1-wire and DS18X20 drivers in the
drivers/onewire directory. The existing ones were pyboard-specific and
not very efficient nor minimal (although the 1-wire driver was written in
pure Python it only worked at large enough CPU frequency).
This commit brings backwards incompatible API changes to the existing
1-wire drivers. User code should be converted to use the new drivers, or
check out the old version of the code and keep a local copy (it should
continue to work unchanged).
The 1-wire bus is defined with fixed timings so there should be no need to
change them dynamically at runtime. Making the timings fixed saves about
270 bytes of code and 20 bytes of RAM.
The reason it was separated is so that the low-level code could be put in
iRAM, for timing reasons. But:
1. Tests show that it's not necessary to have this code in iRAM for it to
function correctly, and taking it out of iRAM reclaims some of that precious
resource. Furthermore, even though these functions were in iRAM there were
some functions that it called (eg pin get/set functions) which were not in
iRAM, so partially defeated the purpose of putting the 1-wire code in iRAM.
2. It's easier to reuse this 1-wire code in other ports if it's in a single
file.
3. If it turns out that certain code does need to be in iRAM then one can
use the MP_FASTCODE macro to do that.
Paul Sokolovsky
Damien George