Create README.md

First short description of the display routine

README.md

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+VBMP
+====
+
+BMP Viewer for the Apple II
+
+Introduction
+============
+This project is based on the work of Arnaud Cocquière and his hommage to Steve Jobs.
+http://www.ctrl-pomme-reset.fr/2011/10/11/hommage/
+
+Unlike most images shown on the Apple II, the image displayed is actually a BMP file 
+without additional conversion. The disk includes the sources for the BMP viewer, so I
+decided to study it and learn a bit of 6502 assemmbly and graphics programming on the
+Apple II.
+Since my Apple IIc supports DHGR graphics I started playing with it to add support to
+16 color BMPs and monochrome pictures in Double High-Res. I thought this could be useful
+for someone else so I asked Arnaud for permission to publish it in GitHub.
+
+Usage
+=====
+The code uses the Merlin Assembler syntax. Just load it in Merlin on the Apple II and it 
+should compile without problems.
+To load BMPs in the DSK Image I recommend Apple Commander, but Cider Press might do as
+well. Just import the BMP as a Raw binary file.
+Using Applesoft you can load the image with the following commands
+BLOAD IMAGE.BMP,A$4000
+BRUN DISPLAY
+
+Supported formats
+=================
+The viewer supports BMP Images with the following resolutions and color depths
+Monochrome (1bit color depth) 280 x 192 px
+Monochrome (1bit color depth) 560 x 192 px
+16 Color (4bit color depth) 140 x 192 px
+The formats are automatically detected based on the horizontal resolution. Using different
+formats as the ones listed may lead to unexpected results since the format check has been
+kept as simple as possible.
+
+