24 lines
767 B
Plaintext
24 lines
767 B
Plaintext
// This file is part of www.nand2tetris.org
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// and the book "The Elements of Computing Systems"
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// by Nisan and Schocken, MIT Press.
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// File name: tools/builtIn/Keyboard.hdl
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/**
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* The keyboard (memory map).
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* Outputs the code of the currently pressed key.
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*
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* The built-in chip implementation has two side effects supplied
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* by the simulator. First, the keyboard memory map is continuously
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* being refreshed from the physical keyboard unit. Second, it
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* displays a keyboard icon and data entry GUI.
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*/
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CHIP Keyboard {
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OUT out[16]; // The ASCII code of the pressed key,
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// or 0 if no key is currently pressed,
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// or one the special codes listed in Figure 5.5.
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BUILTIN Keyboard;
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}
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