This patch allows to configure the DAC resolution in the constructor and
in the init function, eg:
dac = DAC(1, bits=12).
The default resolution is 8 bits for backwards compatibility. The bits
sets the maximum value accepted by write and write_timed methods, being
2**bits - 1.
When using write_timed with 12-bit resolution, the input buffer is
treated as an unsigned half-word array, typecode 'H'.
See PR #1130 for discussion.
As we dn't export constants for TCSANOW, etc., zero makes a good "don't
care" param, and now it will work also under Android Bionic and any other
libc.
It makes much more sense to do constant folding in the parser while the
parse tree is being built. This eliminates the need to create parse
nodes that will just be folded away. The code is slightly simpler and a
bit smaller as well.
Constant folding now has a configuration option,
MICROPY_COMP_CONST_FOLDING, which is enabled by default.
Use CTRL-E to enter paste mode. Prompt starts with "===" and accepts
all characters verbatim, echoing them back. Only control characters are
CTRL-C which cancels the input and returns to normal REPL, and CTRL-D
which ends the input and executes it. The input is executed as though
it were a file. The input is not added to the prompt history.