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+Getting a MicroPython REPL prompt
+=================================
+
+REPL stands for Read Evaluate Print Loop, and is the name given to the
+interactive MicroPython prompt that you can access on your board through
+Zephyr. It is recommended to use REPL to test out your code and run commands.
+
+REPL over the serial port
+-------------------------
+
+The REPL is available on a UART serial peripheral specified for the board by
+the ``zephyr,console`` devicetree node. The baudrate of the REPL is 115200.
+If your board has a USB-serial convertor on it then you should be able to access
+the REPL directly from your PC.
+
+To access the prompt over USB-serial you will need to use a terminal emulator
+program. For a Linux or Mac machine, open a terminal and run::
+
+        screen /dev/ttyACM0 115200
+
+You can also try ``picocom`` or ``minicom`` instead of screen. You may have to use
+``/dev/ttyACM1`` or a higher number for ``ttyACM``. Additional permissions
+may be necessary to access this device (eg group ``uucp`` or ``dialout``, or use sudo).
+For Windows, get a terminal software, such as puTTY and connect via a serial session
+using the proper COM port.
+
+Using the REPL
+--------------
+
+With your serial program open (PuTTY, screen, picocom, etc) you may see a
+blank screen with a flashing cursor. Press Enter (or reset the board) and
+you should be presented with the following text::
+
+        *** Booting Zephyr OS build v2.6.0-rc1-416-g3056c5ec30ad  ***
+        MicroPython v2.6.0-rc1-416-g3056c5ec30 on 2021-06-24; zephyr-frdm_k64f with mk64f12
+        Type "help()" for more information.
+        >>>
+
+Now you can try running MicroPython code directly on your board.
+
+Anything you type at the prompt, indicated by ``>>>``, will be executed after you press
+the Enter key. If there is an error with the text that you enter then an error
+message is printed.
+
+Start by typing the following at the prompt to make sure it is working::
+
+        >>> print("hello world!")
+        hello world!
+
+If you already know some python you can now try some basic commands here. For
+example::
+
+        >>> 1 + 2
+        3
+        >>> 1 / 2
+        0.5
+        >>> 3 * 'Zephyr'
+        ZephyrZephyrZephyr
+
+If your board has an LED, you can blink it using the following code::
+
+        >>>import time
+        >>>from machine import Pin
+
+        >>>LED = Pin(("GPIO_1", 21), Pin.OUT)
+        >>>while True:
+        ...    LED.value(1)
+        ...    time.sleep(0.5)
+        ...    LED.value(0)
+        ...    time.sleep(0.5)
+
+The above code uses an LED location for a FRDM-K64F board (port B, pin 21;
+following Zephyr conventions ports are identified by "GPIO_x", where *x*
+starts from 0). You will need to adjust it for another board using the board's
+reference materials.