Initial commit (a clone of the jsmachines project as of v1.15.3)

blog/2014/07/30/README.md

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+EGA Support
+---
+PCjs v1.14.0 now includes basic EGA support.  It emulates the EGA hardware well enough to pass the IBM EGA BIOS
+diagnostics and run [Windows 1.01](/configs/pc/machines/5160/ega/640kb/win101/) in color.  Check out our
+[Windows 1.01 "Server Array"](/configs/pc/machines/5160/ega/640kb/array/) demo.
+
+![Windows 1.01 "Server Array" Demo](/blog/2014/07/30/win101-array-demo-small.jpg "link:/blog/2014/07/30/win101-array-demo.jpg")
+
+EGA support is added to a **machine.xml** file using two XML elements; eg:
+
+		<video id="videoEGA" model="ega" memory="0x20000" screenwidth="640" screenheight="350"/>
+
+The *model* attribute must be set to "ega" and the *memory* attribute should be set to the amount of memory
+desired on the card; valid memory sizes are:
+ 
+- 0x10000 (64Kb)
+- 0x20000 (128Kb)
+- 0x40000 (256Kb)
+
+As with the MDA and CGA video cards, the *screenwidth* and *screenheight* attributes specify the size of display
+window, which the browser will then scale up or down, unless a specific overall size has been specified on the
+&lt;machine&gt; element.
+
+The second required XML element is a &lt;rom&gt; element to load the EGA ROM; eg:
+
+	<rom id="romEGA" addr="0xc0000" size="0x4000" file="/devices/pc/video/ibm-ega.json" notify="videoEGA"/>
+
+The *notify* attribute must match the *id* of the &lt;video&gt; element, so that the Video component can load
+the initial 8x14 and 8x8 fonts from the ROM.  Support for dynamic loading of fonts from plane 2 of the EGA's memory
+will be added later; however, current support works well enough to allow switching from 25-line mode to 43-line mode,
+which essentially switches from the 8x14 font to the 8x8 font.
+
+The &lt;video&gt; element also supports a *switches* attribute to specify the type of monitor connected to the EGA;
+this attribute corresponds to the actual switch settings on the EGA card; our default *switches* setting is "0110",
+which selects an Enhanced Color Monitor, enabling the EGA's maximum resolution of 640x350.
+
+*[@jeffpar](http://twitter.com/jeffpar)*  
+*July 30, 2014*