CS 1020 - Week #13 - April 16th, 2013

1. CSMA/CD - many share one ethernet cable road. How to prevent and respond to collisions.

2. Cache memory and the fetch/execute cycle.

3. The concept of a SUBNET MASK and how it relates to IP numbers and TCP/IP protocol suite.

4. Review of Fetch/Execute Cycle relates to Cache Memory and to the TIC Tiny Imaginary Computer model.

5. Flash ActionScript 3.0 experiment to try...

   var n:uint = 0;
   var lineCanvas:Shape = new Shape();
   addChild(lineCanvas);
    
   function drawLine(e:Event):void {
      with (lineCanvas) {
          graphics.moveTo(275, 200);
    
          var c:int = Math.floor(Math.random()* 0xFFFFFF);
          if (n % 3 == 0) {
              graphics.lineStyle(5, 0xFF0000);
          } else if (n % 3 == 1) {
              graphics.lineStyle(5, 0xFFFFFF);
          } else {
              graphics.lineStyle(5, 0x0000FF);
          }
    
          var x:Number = Math.random()* 550;
          var y:Number = Math.random()*400;
    
          graphics.lineTo(x, y);
          n++;
      }
   }
   
   addEventListener(Event.ENTER_FRAME, drawLine);
    
   for (var i:uint = 1; i <= 10000; i++) {
       drawLine2();
   }
   
   function drawLine2():void {
      with (lineCanvas) {
   	// graphics.clear();
   	graphics.moveTo(275, 200);
    
   	var c:int = Math.floor(Math.random()* 0xFFFFFF);
   	graphics.lineStyle(1, c);
    
   	var x:Number = Math.random()* 550;
   	var y:Number = Math.random()*400;
    
   	var xDist = x - 275;
   	var yDist = y - 200;
   
   	if ( Math.sqrt( xDist*xDist + yDist*yDist ) <= 200 ) {
   	     graphics.lineTo(x, y);
           }
      }
   }
   

6. The Striker Flash ActionScript 3.0 application is the basis for a fun interactive game.

7. "DOS" or command prompt Batch files, Internal and External commands, CMD.exe, etc.

   More on BATCH files and commands.