MicroPython guarantees '/' to be a path separator, so extra constant taking
precious ROM space are not needed. MicroPython never had such constant, only
one vendor port had it (now unmaintained).
This new function controls what happens on a hard-fault:
- debugging disabled: board will do a reset
- debugging enabled: board will print registers and stack and flash LEDs
The default is disabled, ie to do a reset. This is different to previous
behaviour which flashed the LEDs and waited indefinitely.
machine.time_pulse_us() is intended to provide very fine timing, including
while working with signal bursts, where each transition is tracked in row.
Throwing and handling an exception may take too much time and "signal loss".
So instead, in case of a timeout, just return negative value. Cases of
timeout while waiting for initial signal stabilization, and during actual
timing, are recognized.
The documentation is updated accordingly, and rewritten somewhat to clarify
the function behavior.
New keyword option in constructor and init() method is "dma=<bool>".
DMA is now disabled by default for I2C transfers because it currently does
not handle I2C bus errors very well (eg if slave device doesn't ACK or
NACK correctly during a transfer).
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.
Clarify the class implements master side of the protocol, also put adhoc
WiPy paramter after the generic, described in the current Hardware API
version.
The memory read/write I2C functions now take an optional keyword-only
parameter that specifies the number of bits in the memory address.
Only mem-addrs that are a multiple of 8-bits are supported (otherwise
the behaviour is undefined).
Due to the integer type used for the address, for values larger than 32
bits, only 32 bits of address will be sent, and the rest will be padded
with 0s. Right now no exception is raised when that happens. For values
smaller than 8, no address is sent. Also no exception then.
Tested with a VL6180 sensor, which has 16-bit register addresses.
Due to code refactoring, this patch reduces stmhal and esp8266 builds
by about 50 bytes.
machine.POWER_ON is renamed to machine.PWRON_RESET to match other
reset-cause constants that all end in _RESET. The cc3200 port keeps a
legacy definition of POWER_ON for backwards compatibility.
