Project 04, leider war Fill nicht meins

projects/04/abgabe/Fill.asm

@@ -0,0 +1,78 @@
+// 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/04/Fill.asm
+
+// Runs an infinite loop that listens to the keyboard input.
+// When a key is pressed (any key), the program blackens the screen,
+// i.e. writes "black" in every pixel;
+// the screen should remain fully black as long as the key is pressed. 
+// When no key is pressed, the program clears the screen, i.e. writes
+// "white" in every pixel;
+// the screen should remain fully clear as long as no key is pressed.
+
+// Put your code here.
+
+@8192  // 32*256  --> 32 16er pro Zeile
+D=A
+@ENDPOS    // in @16
+M=D
+
+(LOOP)
+    @SCREEN     //Screen-Einstiegsadresse
+    D=A
+    @ScreenStart        //@SCREEN 16384 --> @17
+    M=D
+
+    @i          //Zähler = 0 18
+    M=0
+
+    @KBD        //24576
+    D=M         //Tastatureingabe ?
+
+    @WEISS
+    D; JEQ      //WEISS WENN D == 0
+    @SCHWARZ    //SPRINGE ZU SCHWARZ
+    D; JNE      //WENN NICHT 0
+
+(SCHWARZ)
+    @ENDPOS
+    D=M
+    @i
+    D=D-M       //ENDPOS -1 = 0 ?  DANN ZU LOOP
+    @LOOP
+    D;JEQ   
+
+    @ScreenStart 
+    A=M
+    M=-1        //SETZE -1 == SCHWARZ
+
+    @i
+    M=M+1       //i++
+
+    @ScreenStart 
+    M=M+1
+
+    @SCHWARZ
+    0;JMP
+
+(WEISS)
+    @ENDPOS
+    D=M
+    @i
+    D=D-M       //ENDPOS -1 = 0 ?  DANN ZU LOOP 
+    @LOOP
+    D;JEQ   
+
+    @ScreenStart 
+    A=M
+    M=0         //SETZE 0 == WEISS
+
+    @i
+    M=M+1       //i++
+
+    @ScreenStart 
+    M=M+1
+
+    @WEISS
+    0;JMP