2015-06-04 22:53:26 +00:00
|
|
|
Getting a MicroPython REPL prompt
|
|
|
|
=================================
|
2014-09-25 16:21:59 +00:00
|
|
|
|
|
|
|
REPL stands for Read Evaluate Print Loop, and is the name given to the
|
2015-06-04 22:53:26 +00:00
|
|
|
interactive MicroPython prompt that you can access on the pyboard. Using
|
2014-09-25 16:21:59 +00:00
|
|
|
the REPL is by far the easiest way to test out your code and run commands.
|
|
|
|
You can use the REPL in addition to writing scripts in ``main.py``.
|
|
|
|
|
|
|
|
To use the REPL, you must connect to the serial USB device on the pyboard.
|
|
|
|
How you do this depends on your operating system.
|
|
|
|
|
|
|
|
Windows
|
|
|
|
-------
|
|
|
|
|
|
|
|
You need to install the pyboard driver to use the serial USB device.
|
|
|
|
The driver is on the pyboard's USB flash drive, and is called ``pybcdc.inf``.
|
|
|
|
|
|
|
|
To install this driver you need to go to Device Manager
|
|
|
|
for your computer, find the pyboard in the list of devices (it should have
|
|
|
|
a warning sign next to it because it's not working yet), right click on
|
|
|
|
the pyboard device, select Properties, then Install Driver. You need to
|
|
|
|
then select the option to find the driver manually (don't use Windows auto update),
|
|
|
|
navigate to the pyboard's USB drive, and select that. It should then install.
|
|
|
|
After installing, go back to the Device Manager to find the installed pyboard,
|
|
|
|
and see which COM port it is (eg COM4).
|
2015-01-06 16:09:49 +00:00
|
|
|
More comprehensive instructions can be found in the
|
|
|
|
`Guide for pyboard on Windows (PDF) <http://micropython.org/resources/Micro-Python-Windows-setup.pdf>`_.
|
|
|
|
Please consult this guide if you are having problems installing the driver.
|
2014-09-25 16:21:59 +00:00
|
|
|
|
|
|
|
You now need to run your terminal program. You can use HyperTerminal if you
|
|
|
|
have it installed, or download the free program PuTTY:
|
2014-11-02 23:37:02 +00:00
|
|
|
`putty.exe <http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html>`_.
|
2014-09-25 16:21:59 +00:00
|
|
|
Using your serial program you must connect to the COM port that you found in the
|
|
|
|
previous step. With PuTTY, click on "Session" in the left-hand panel, then click
|
|
|
|
the "Serial" radio button on the right, then enter you COM port (eg COM4) in the
|
|
|
|
"Serial Line" box. Finally, click the "Open" button.
|
|
|
|
|
|
|
|
Mac OS X
|
|
|
|
--------
|
|
|
|
|
|
|
|
Open a terminal and run::
|
|
|
|
|
|
|
|
screen /dev/tty.usbmodem*
|
|
|
|
|
2014-10-31 01:37:19 +00:00
|
|
|
When you are finished and want to exit screen, type CTRL-A CTRL-\\.
|
2014-09-25 16:21:59 +00:00
|
|
|
|
|
|
|
Linux
|
|
|
|
-----
|
|
|
|
|
|
|
|
Open a terminal and run::
|
|
|
|
|
|
|
|
screen /dev/ttyACM0
|
|
|
|
|
|
|
|
You can also try ``picocom`` or ``minicom`` instead of screen. You may have to
|
|
|
|
use ``/dev/ttyACM1`` or a higher number for ``ttyACM``. And, you may need to give
|
|
|
|
yourself the correct permissions to access this devices (eg group ``uucp`` or ``dialout``,
|
|
|
|
or use sudo).
|
|
|
|
|
|
|
|
Using the REPL prompt
|
|
|
|
---------------------
|
|
|
|
|
2015-06-04 22:53:26 +00:00
|
|
|
Now let's try running some MicroPython code directly on the pyboard.
|
2014-09-25 16:21:59 +00:00
|
|
|
|
|
|
|
With your serial program open (PuTTY, screen, picocom, etc) you may see a blank
|
|
|
|
screen with a flashing cursor. Press Enter and you should be presented with a
|
2015-06-04 22:53:26 +00:00
|
|
|
MicroPython prompt, i.e. ``>>>``. Let's make sure it is working with the obligatory test::
|
2014-09-25 16:21:59 +00:00
|
|
|
|
|
|
|
>>> print("hello pyboard!")
|
|
|
|
hello pyboard!
|
|
|
|
|
|
|
|
In the above, you should not type in the ``>>>`` characters. They are there to
|
|
|
|
indicate that you should type the text after it at the prompt. In the end, once
|
|
|
|
you have entered the text ``print("hello pyboard!")`` and pressed Enter, the output
|
|
|
|
on your screen should look like it does above.
|
|
|
|
|
|
|
|
If you already know some python you can now try some basic commands here.
|
|
|
|
|
|
|
|
If any of this is not working you can try either a hard reset or a soft reset;
|
|
|
|
see below.
|
|
|
|
|
|
|
|
Go ahead and try typing in some other commands. For example::
|
|
|
|
|
|
|
|
>>> pyb.LED(1).on()
|
|
|
|
>>> pyb.LED(2).on()
|
|
|
|
>>> 1 + 2
|
|
|
|
3
|
|
|
|
>>> 1 / 2
|
|
|
|
0.5
|
|
|
|
>>> 20 * 'py'
|
|
|
|
'pypypypypypypypypypypypypypypypypypypypy'
|
|
|
|
|
|
|
|
Resetting the board
|
|
|
|
-------------------
|
|
|
|
|
|
|
|
If something goes wrong, you can reset the board in two ways. The first is to press CTRL-D
|
2015-06-04 22:53:26 +00:00
|
|
|
at the MicroPython prompt, which performs a soft reset. You will see a message something like ::
|
2014-09-25 16:21:59 +00:00
|
|
|
|
|
|
|
>>>
|
|
|
|
PYB: sync filesystems
|
|
|
|
PYB: soft reboot
|
|
|
|
Micro Python v1.0 on 2014-05-03; PYBv1.0 with STM32F405RG
|
|
|
|
Type "help()" for more information.
|
|
|
|
>>>
|
|
|
|
|
|
|
|
If that isn't working you can perform a hard reset (turn-it-off-and-on-again) by pressing the RST
|
|
|
|
switch (the small black button closest to the micro-USB socket on the board). This will end your
|
|
|
|
session, disconnecting whatever program (PuTTY, screen, etc) that you used to connect to the pyboard.
|
|
|
|
|
|
|
|
If you are going to do a hard-reset, it's recommended to first close your serial program and eject/unmount
|
|
|
|
the pyboard drive.
|