Created FAQ #11 (markdown)

FAQ-#11.md

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+### How do store a reference to the NeoPixelBus in another class?
+
+Since the NeoPixelBus is a template class; you can't just store a reference to it using older models.  But there are two ways to accomplish this.
+
+My first recommendation is to make the containing class a template also.  The following sketch demonstrates this all in one file.  The actual template class can be in another file.
+```
+#include <NeoPixelBus.h>
+
+typedef  NeoPixelBus<NeoGrbFeature, Neo800KbpsMethod>  NeoPixelBusType;
+
+NeoPixelBusType strip(4, 2);
+
+// example class using a reference; requires all code to be in the include
+template<typename T_PIXEL_METHOD> class PixelRef
+{
+  public:
+  PixelRef(T_PIXEL_METHOD& pixelStrip) :
+    _strip(pixelStrip) {
+      
+    }
+
+  void Draw() {
+    _strip.Show();
+  }
+  
+  private:
+  T_PIXEL_METHOD& _strip;
+};
+
+PixelRef<NeoPixelBusType> myPixelRef(strip);
+
+void setup() {
+    strip.Begin();
+    strip.Show();
+}
+
+void loop() {
+    myPixelRef.Draw();
+}
+```
+
+The second method to accomplish this uses a normal class definition; but has the limitation that class must be fully implemented in a header file due to the NeoPixelBus type is defined in the sketch.
+```
+#include <NeoPixelBus.h>
+
+typedef  NeoPixelBus<NeoGrbFeature, Neo800KbpsMethod>  NeoPixelBusType;
+
+NeoPixelBusType strip(4, 2);
+
+// example class using a reference; requires all code to be in the include
+template<typename T_PIXEL_METHOD> class PixelRef {
+  public:
+  PixelRef(T_PIXEL_METHOD& pixelStrip) :
+    _strip(pixelStrip) {
+    }
+
+  void Draw()  {
+    _strip.Show();
+  }
+  
+  private:
+  T_PIXEL_METHOD& _strip;
+};
+
+
+PixelRef<NeoPixelBusType> myPixelRef(strip);
+
+void setup()
+{
+    strip.Begin();
+    strip.Show();
+}
+
+void loop()
+{
+    myPixelRef.Draw();
+}
+```