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rm-hull · Jan 22, 2017 · 676a861 · 676a861
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diff --git a/CHANGES.rst b/CHANGES.rst
@@ -4,7 +4,7 @@ ChangeLog
 +------------+----------------------------------------------------------------------+------------+
 | Version    | Description                                                          | Date       |
 +============+======================================================================+============+
-| *Upcoming* | *TBC*                                                                |            |
+| *Upcoming* | * Add support for WS2812 NeoPixel strips/arrays                      |            |
 +------------+----------------------------------------------------------------------+------------+
 | **0.3.3**  | * Fix for dot muncher: not handling full-stop at line end            | 2017/01/21 |
 |            | * Documentation updates                                              |            |

diff --git a/doc/install.rst b/doc/install.rst
@@ -69,11 +69,25 @@ Board Pin    Name   Remarks       RPi Pin   RPi Function
 WS2812 NeoPixels (DMA)
 ^^^^^^^^^^^^^^^^^^^^^^
 
-Pre-requisites
-""""""""""""""
-
 GPIO pin-outs
 """""""""""""
+Typically, neopixels reqire VCC, VSS (GND) and DI pins connecting to the
+Raspberry Pi, where the DI pin is usually connected to a PWM control pin
+such as GPIO 18.
+
+============ ====== ============= ========= ====================
+Board Pin    Name   Remarks       RPi Pin   RPi Function
+------------ ------ ------------- --------- --------------------
+1            DO     Data Out      -         -
+2            DI     Data In       12        GPIO 18 (PWM0)
+3            VCC    +5V Power     2         5V0
+4            NC     Not connected -         -
+5            VDD    Not connected -         -
+6            VSS    Ground        6         GND
+============ ====== ============= ========= ====================
+
+The DO pin should be connected to the DI pin on the next (daisy-chained)
+neopixel, while the VCC and VSS are supplied in-parallel to all LED's.
 
 Installing from PyPi
 ^^^^^^^^^^^^^^^^^^^^
@@ -99,8 +113,8 @@ Raspbian
 .. code:: bash
 
   $ cd luma.led_matrix
-  $ sudo apt-get install python-dev python-pip
-  $ sudo pip install spidev
+  $ sudo usermod -a -G spi,gpio pi
+  $ sudo apt-get install python-dev python-pip libfreetype6-dev libjpeg8-dev libsdl1.2-dev
   $ sudo python setup.py install
 
 Arch Linux
@@ -109,5 +123,4 @@ Arch Linux
 
   cd luma.led_matrix
   pacman -Sy base-devel python2
-  pip install spidev
   python2 setup.py install
diff --git a/doc/python-usage.rst b/doc/python-usage.rst
@@ -260,16 +260,22 @@ initialize the device with ``width=N`` and ``height=N`` attributes instead:
        draw.line((6, 0, 6, device.height), fill="violet")
        draw.line((7, 0, 7, device.height), fill="white")
 
+.. note::
+   The neopixel driver uses the `ws2812 <https://pypi.python.org/pypi/ws2812>`_
+   PyPi package to interface to the daisychained LEDs. It uses DMA (direct memory
+   access) via ``/dev/mem`` which means that it has to run in privileged mode
+   (via ``sudo`` root access).
+
 Examples
 ^^^^^^^^
 Ensure you have followed the installation instructions in the next section.
 Run the example code as follows::
 
-  $ sudo python examples/matrix_demo.py
+  $ python examples/matrix_demo.py
 
 or::
 
-  $ sudo python examples/sevensegment_demo.py
+  $ python examples/sevensegment_demo.py
 
 or::