Remove trailing whitespace and clean up comments

12/Keyboard.jack

@@ -53,9 +53,6 @@ class Keyboard {
         // Echo (except backspace)
         if (key < 129) {
              // Handle newline specially for cleaner output?
-             // Output.printChar(128) might not do NewLine with my Output implementation unless I updated it?
-             // My Output implementation (Step 240) does NOT check for 128.
-             // So I should call println() if 128.
              if (key = 128) {
                  do Output.println();
              } else {
@@ -63,8 +60,6 @@ class Keyboard {
              }
         }
         // If key > 129 (arrows etc), printChar might print garbage or square.
-        // Spec usually implies echoing everything or being selective.
-        // I'll stick to echoing only standard chars + newline.
 
         return key;
     }

12/Output.jack

@@ -180,14 +180,6 @@ class Output {
         let cursorRow = i;
         let cursorCol = j;
         return;
-        // Spec says "and erases the character displayed there"?
-        // Usually moveCursor just moves it. The cursor 'character' itself (black square) 
-        // is typically implemented by blinking or drawing.
-        // Project 12 spec: "A cursor, implemented as a small filled square, indicates where the next character will be displayed."
-        // And "erases the character displayed there"? Maybe erases the *cursor* from old location?
-        // Or erases the *content*? "Erases the character displayed there" usually implies drawing black square (cursor) or clearing it?
-        // Wait, standard implementation usually just updates coordinates.
-        // I will assume simple update.
     }
 
     /** Displays the given character at the cursor location,

12/Screen.jack

@@ -61,7 +61,6 @@ class Screen {
         let address = 16384 + (y * 32) + (x / 16);
         let value = Memory.peek(address);
 
-        // Calculate 2^(x%16) logic inline or helper? 
         // x & 15 is x % 16
         let mask = powersOfTwo[x & 15];
 

12/String.jack

@@ -19,10 +19,6 @@ class String {
     constructor String new(int maxLength) {
         if (maxLength = 0) {
             let maxLength = 1; // min length 1 for alloc safety?
-            // Actually spec says allocation of 0 size might happen. 
-            // My Array.new -> Memory.alloc handles 0 size by returning a 1 word block (header-1?? No).
-            // Let's alloc 0 if needed.
-            // If maxLength is 0, we can't really store anything.
         }
         if (maxLength > 0) {
             let buffer = Array.new(maxLength);

12/Sys.jack

@@ -10,8 +10,11 @@ class Sys {
 
     /** Performs all the initializations required by the OS. */
     function void init() {
+        // do Memory.poke(8000, 1); // Start
         do Memory.init();
+        // do Memory.poke(8000, 2); // Mem init done
         do Math.init();
+        // do Memory.poke(8000, 3); // Math init done
         do Screen.init();
         do Output.init();
         do Keyboard.init();
@@ -35,10 +38,8 @@ class Sys {
              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;
              }