diff -r 000000000000 -r 88d965579617 components/u8g2/doc/u8g2.txt
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+
+U8glib V2: Name and project goals
+
+https://github.com/olikraus/u8g2
+
+U8g2 = Universal 8bit Graphics
+
+[U]niversal: Support for many displays ans development platforms
+[8]bit: Initial focus had been 8 bit microcontroller systems
+[g]raphics": U8g2 is a graphics library with focus on monochrome graphics displays
+[2]: Second generation and successor of u8glib
+
+
+U8glib V2 Goals
+
+- Support for monochrome LCDs and OLEDs 
+- Focus on "monochrome"
+- Low memory footprint
+
+
+U8glib V2: Features and Limitations
+
+- Full Memory Buffer 
+- 3-wire-SPI
+- Support for Arduino Libraries SPI and TWI
+
+- Unicode Support
+  Unicode plane 0 (Basic Multilingual Plane, BMP, glyphs with 0x0000-0xffff) 
+  is fully supported.
+	Limitation: Unicode planes > 0 are not supported
+- UTF-8 Support
+  2 and 3 byte sequences are detected and handled.
+  Limitation:  
+	Behavior for sequences with more than 3 bytes is unknown.
+
+- Large number of fonts
+
+- Compilation speed improved (font data)
+
+- "Text only" sub library: U8x8
+
+- Hardware supported display flip
+
+- Better hardware support: Tested with avr, esp8266 and sam architectures.
+
+
+u8g vs. u8g2
+
+Major Changes (Code rework required)
+
+- The name of the include file has changed: Use 
+    #include "U8g2lib.h"
+- The native type for pixel coordinates has changed to u8g2_uint_t
+  Use the following line to redefine this at the beginning of your code
+    typedef u8g2_uint_t u8g_uint_t;
+
+- Old Arduino IDE 00xx (before 1.00) is not supported any more.
+	ARDUINO macro must be >= 100
+- begin() must be called (this was optional in U8glib)
+- constructor contains name of communicaton interface and 
+    also contains the display orientation as first argument
+- u8g2.drawStr90 does not exist any more, use
+      void u8g2_SetFontDirection(u8g2_t *u8g2, uint8_t dir);
+- "P" versions of the string functions are not yet implemented.
+	This includes drawStrP(), getStrWidthP(), etc
+	Use the print function with the F() macro instead.
+- In U8glib font transparency was defined in the .begin() statement. This is now
+      handled by setFontMode(). 
+- Screen rotation is handled by the constructor in u8g2
+	The functions undoRotation, setRot90, setRot180 and setRot270 are
+	replaced by the first argument of the constructor
+- Screen scaling is not there in u8g2
+	It is completly removed, there are no corresponding function in u8g2 
+	for undoScale() and setScale2x2().
+- setColorEntry(), setHiColor(), setHiColorByRGB(), setRGB: Not supported any more
+	(u8g2 focus are monochrome displays, use Ucglib instead)
+- getMode(): Is not available any more because there is only one monochrome mode.	
+- setDefaultForegroundColor(), setDefaultBackgroundColor() and 
+	setDefaultMidColor() are not required any more. These functions do not
+	exist in U8g2. Use setDrawColor() instead.
+- getFontLineSpacing() and setFontLineSpacingFactor() are not supported any more. 
+- getStrPixelWidth() is replaced by getStrWidth() 
+- setHardwareBackup() not supported any more. Might be implemented later
+- Cursor functions are not available. This includes:
+	setCursorFont(), setCursorStyle(), setCursorPos(), setCursorColor(),
+	enableCursor(), disableCursor(), drawCursor()
+- Virtual screen handling is not supported:
+	setVirtualScreenDimension(), addToVirtualScreen()
+	
+Minor Changes (Code update might be required)
+
+- U8g2 drawTriangle() expects signed arguments (u8glib expects unsigned arguments)
+- U8g2 has different font names. Some of the old font names are known to u8g2 and are
+	mapped automatically. If the font name is unknown, please choose a different font from the font list.
+
+Change Notes (No code change required)
+
+- sleepOn(), sleepOff(): supported, but better user setPowerSave()
+- setColorIndex() and getColorIndex() are renamed to setDrawColor() and 
+	getDrawColor(). The old names are still supported.
+- getFontAscent() and getFontDescent() are renamed to getAscent() and getDescent()
+	The old names are still supported.
+- Signal names are renamed in the constructor calls:
+	U8glib sck == U8g2 clock
+	U8glib mosi == U8g2 data
+	U8glib a0 == U8g2 dc
+- getHeight() renamed to getDisplayHeight(), old name still exists
+- getWidth() renamed to getDisplayWidth(), old name still exists
+	
+