Basic documentation for the UDP led driver

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doc/UDP_led_driver.txt

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+BACKGROUND
+---------------------------------------------------------
+The UDP led device type can be used to send LED data over UDP packets.
+It was originally designed to support an ESP8266 Wifi module based WS2812
+LED strip controller.
+
+I've used this to support :
+-	A string of 600 LEDs as xmas decorations
+	The effects development kit is great for these scenarios
+
+-	a 61 LED collection of concentric circles
+	This has been used as a "night light" and a super lo-res
+	TV
+
+In each of these  cases, the hyperion-remote iOS app is a great way to 
+control the effects.
+
+
+CONFIG
+---------------------------------------------------------
+Simple example for devices that support a raw binary protocol.
+        "device" :
+        {
+                "name"       : "MyPi",
+                "type"       : "udp",
+                "output"     : "esp201-0.home:2391", "protocol" : 0,
+                "rate"       : 1000000,
+                "colorOrder" : "grb"
+        },
+
+
+
+If you are using an ESP8266/Arduino device with a long LED strip, you chould use this alternate protocol.
+The ESP8266/Arduino doesnt support datagram re-assembly so will never see any udp packets greater than 1450.
+        "device" :
+        {
+                "name"       : "MyPi",
+                "type"       : "udp",
+//              "output"     : "esp201-0.home:2392", "protocol" : 2, "maxpacket" : 1450,
+                "rate"       : 1000000,
+                "colorOrder" : "rgb"
+        },
+
+PROTOCOL
+---------------------------------------------------------
+Simple UDP packets are sent.
+
+Packet Format protocol 0:
+3 bytes per LED as R, G, B
+
+Packet Format protocol 2:
+0: update number & 0xf;
+1: fragment of this update
+2: 1st led# of this update - high byte
+3: 1st led# of this update - low byte
+4..n 3 bytes per LED as R, G, B
+