project12 - complete

12/Sys.jack

@@ -10,18 +10,49 @@ class Sys {
 
     /** Performs all the initializations required by the OS. */
     function void init() {
+        do Memory.init();
+        do Math.init();
+        do Screen.init();
+        do Output.init();
+        do Keyboard.init();
+        do Main.main();
+        do Sys.halt();
+        return;
     }
 
     /** Halts the program execution. */
     function void halt() {
+        while (true) {}
+        return;
     }
 
     /** Waits approximately duration milliseconds and returns.  */
     function void wait(int duration) {
+        var int i, j;
+        let i = 0;
+        
+        while (i < duration) {
+             let j = 0;
+             // Calibration: loop count determines delay.
+             // On typical VM emulator settings (Fast), ~50-100 loops might be 1ms?
+             // User requested 2 seconds wait in test.
+             // "WaitWithInput" sample in Snake used loop for waiting.
+             
+             // Standard N2T value is roughly 50-100.
+             while (j < 50) {
+                 let j = j + 1;
+             }
+             let i = i + 1;
+        }
+        return;
     }
 
     /** Displays the given error code in the form "ERR<errorCode>",
      *  and halts the program's execution. */
     function void error(int errorCode) {
+        do Output.printString("ERR");
+        do Output.printInt(errorCode);
+        do Sys.halt();
+        return;
     }
 }