echo.asm completed + screen.asm started

vaja2/zaslon/screen.asm

@@ -0,0 +1,69 @@
+SCREEN START 0 
+    LDA #65
+    JSUB scrfill
+    JSUB scrclear    
+
+HALT J HALT
+    END SCREEN
+
+scrfill     STA znak    
+loop        LDA y 
+            MUL scrcols
+            ADD screen
+            ADD x
+            STA pix_ptr
+            LDA znak
+            STCH @pix_ptr
+            LDA x
+            ADD #1
+            STA x
+            COMP scrrows
+            JLT loop
+            CLEAR A
+            STA x
+            LDA y
+            ADD #1
+            STA y 
+            COMP scrcols
+            JLT loop
+            
+            LDA znak
+            RSUB
+
+
+.address = screen + y * scrcols + x
+scrclear    LDA y 
+            MUL scrcols
+            ADD screen
+            ADD x
+            STA pix_ptr
+            CLEAR A
+            STCH @pix_ptr
+            LDA x
+            ADD #1
+            STA x
+            COMP scrrows
+            JLT scrclear
+            CLEAR A
+            STA x
+            LDA y
+            ADD #1
+            STA y 
+            COMP scrcols
+            JLT scrclear
+        
+            CLEAR A
+            STA x
+            STA y
+            RSUB        
+  
+
+
+znak WORD 0 
+x WORD 0 
+y WORD 0
+pix_ptr WORD 0 
+screen WORD X'00B800'
+scrcols WORD 25 
+scrrows WORD 80
+scrlen WORD 2000