Some important changes to the way the file system is structured on the
pyboard:
1. 0: and 1: drive names are now replaced with POSIX inspired
directories, namely /flash and /sd.
2. Filesystem now supports the notion of a current working directory.
Supports the standard Python way of manipulating it: os.chdir and
os.getcwd.
3. On boot up, current directory is /flash if no SD inserted, else /sd
if SD inserted. Then runs boot.py and main.py from the current dir.
This is the same as the old behaviour, but is much more consistent and
flexible (eg you can os.chdir in boot.py to change where main.py is run
from).
4. sys.path (for import) is now set to '' (current dir), plus /flash
and /flash/lib, and then /sd and /sd/lib if SD inserted. This, along
with CWD, means that import now works properly. You can import a file
from the current directory.
5. os.listdir is fixed to return just the basename, not the full path.
See issue #537 for background and discussion.
For accel to start-up reliably, need to wait 30ms between on/off, and
30ms for it to enter active mode. With this fix the accel can be read
immediately after initialising it.
Addresses issue #763.
Before, pyb.stdin/pyb.stdout allowed some kind of access to the USB VCP
device, but it was basic access.
This patch adds a proper USB_VCP class and object with much more control
over the USB VCP device. Create an object with pyb.USB_VCP(), then use
this object as if it were a UART object. It has send, recv, read,
write, and other methods. send and recv allow a timeout to be specified.
Addresses issue 774.
The user code should call micropython.alloc_emergency_exception_buf(size)
where size is the size of the buffer used to print the argument
passed to the exception.
With the test code from #732, and a call to
micropython.alloc_emergenncy_exception_buf(100) the following error is
now printed:
```python
>>> import heartbeat_irq
Uncaught exception in Timer(4) interrupt handler
Traceback (most recent call last):
File "0://heartbeat_irq.py", line 14, in heartbeat_cb
NameError: name 'led' is not defined
```
Recent changes to builtin print meant that print was printing to the
mp_sys_stdout_obj, which was sending data raw to the USB CDC device.
The data should be cooked so that \n turns into \r\n.
With unicode enabled, this patch allows reading a fixed number of
characters from text-mode streams; eg file.read(5) will read 5 unicode
chars, which can made of more than 5 bytes.
For an ASCII stream (ie no chars > 127) it only needs to do 1 read. If
there are lots of non-ASCII chars in a stream, then it needs multiple
reads of the underlying object.
Adds a new test for this case. Enables unicode support by default on
unix and stmhal ports.
Conflicts:
stmhal/pin_named_pins.c
stmhal/readline.c
Renamed HAL_H to MICROPY_HAL_H. Made stmhal/mphal.h which intends to
define the generic Micro Python HAL, which in stmhal sits above the ST
HAL.
As stack checking is enabled by default, ports which don't call
stack_ctrl_init() are broken now (report RuntimeError on startup). Save
them trouble and just init stack control framework in interpreter init.
