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