projects/12/SysTest/Main.jack


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// This file is part of www.nand2tetris.org
// and the book "The Elements of Computing Systems"
// by Nisan and Schocken, MIT Press.
// File name: projects/12/SysTest/Main.jack

/** Test program for the OS Sys class. */
class Main {

    /** Tests the wait method of the Sys class. */
    function void main() {
        var char key;

        do Output.printString("Wait test:");
        do Output.println();
        do Output.printString("Press any key. After 2 seconds, another message will be printed:");

        while (key = 0) {
	        let key = Keyboard.keyPressed();
        }
        while (~(key = 0)) {
            let key = Keyboard.keyPressed();
        }
        
        do Sys.wait(2000);

        do Output.println();
        do Output.printString("Time is up. Make sure that 2 seconds elapsed.");
        
        return;
    }
}