Refactor of CRTC

src/main/java/com/loomcom/symon/devices/Crtc.java

@@ -2,11 +2,9 @@ package com.loomcom.symon.devices;
 
 import com.loomcom.symon.exceptions.MemoryAccessException;
 import com.loomcom.symon.exceptions.MemoryRangeException;
-import com.loomcom.symon.ui.CrtPanel;
 
-import java.io.BufferedInputStream;
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.util.logging.Logger;
 
 
 /**
@@ -14,60 +12,101 @@ import java.io.IOException;
  */
 public class Crtc extends Device {
 
-    public static final int CHAR_WIDTH = 8;
-    public static final int CHAR_HEIGHT = 8;
-    public static final int SCAN_LINES = 9;
-    public static final int COLUMNS = 40;
-    public static final int ROWS = 25;
-    public static final int SCALE = 2;
+    private static final Logger logger = Logger.getLogger(Crtc.class.getName());
 
-    public static final int REGISTER_SELECT = 0;
-    public static final int REGISTER_WRITE = 1;
 
-    public static String CHAR_ROM_RESOURCE = "/pet.rom";
+    // Memory locations in the CRTC address space
+    public static final int REGISTER_SELECT          = 0;
+    public static final int REGISTER_WRITE           = 1;
+
+    // Registers
+    public static final int HORIZONTAL_TOTAL         = 0;
+    public static final int HORIZONTAL_DISPLAYED     = 1;
+    public static final int HORIZONTAL_SYNC_POSITION = 2;
+    public static final int H_V_SYNC_WIDTHS          = 3;
+    public static final int VERTICAL_TOTAL           = 4;
+    public static final int VERTICAL_TOTAL_ADJUST    = 5;
+    public static final int VERTICAL_DISPLAYED       = 6;
+    public static final int VERTICAL_SYNC_POSITION   = 7;
+    public static final int MODE_CONTROL             = 8;
+    public static final int SCAN_LINE                = 9;
+    public static final int CURSOR_START             = 10;
+    public static final int CURSOR_END               = 11;
+    public static final int DISPLAY_START_HIGH       = 12;
+    public static final int DISPLAY_START_LOW        = 13;
+    public static final int CURSOR_POSITION_HIGH     = 14;
+    public static final int CURSOR_POSITION_LOW      = 15;
+    public static final int LPEN_HIGH                = 16;
+    public static final int LPEN_LOW                 = 17;
+
+
+    /*
+     * These will determine how the Character ROM is decoded,
+     * and are Character ROM dependent.
+     */
+
+    // R1 - Horizontal Displayed
+    private int horizontalDisplayed;
+
+    // R6 - Vertical Displayed
+    private int verticalDisplayed;
+
+    // R9 - Scan Lines: Number of scan lines per character, including spacing.
+    private int scanLinesPerRow;
+
+    // R10 - Cursor Start / Cursor Mode
+    private int cursorStartLine;
+    private boolean cursorEnabled;
+    private int cursorBlinkRate;
+
+    // R11 - Cursor End
+    private int cursorStopLine;
+
+    // R12, R13 - Display Start Address: The starting address in the video RAM of the displayed page.
+    private int startAddress;
+
+    // R14, R15 - Cursor Position
+    private int cursorPosition;
+
+    // The size, in bytes, of a displayed page of characters.
+    private int pageSize;
 
-    private CrtPanel crtPanel;
     private int currentRegister = 0;
 
-    public Crtc(int deviceAddress, Memory memory, int videoRamStartAddress) throws MemoryRangeException, IOException {
+    private Memory memory;
+
+    public Crtc(int deviceAddress, Memory memory) throws MemoryRangeException, IOException {
         super(deviceAddress, 2, "CRTC");
-        this.crtPanel = new CrtPanel(loadCharRom(CHAR_ROM_RESOURCE), memory.getDmaAccess(), COLUMNS, ROWS,
-                                     CHAR_WIDTH, CHAR_HEIGHT,
-                                     SCALE, SCALE, videoRamStartAddress);
-    }
+        this.memory = memory;
 
-    private byte[] loadCharRom(String resource) throws IOException {
-        BufferedInputStream bis = null;
-        try {
-            bis = new BufferedInputStream(this.getClass().getResourceAsStream(resource));
-            ByteArrayOutputStream bos = new ByteArrayOutputStream();
-            while (bis.available() > 0) {
-                bos.write(bis.read());
-            }
-            bos.flush();
-            bos.close();
-            return bos.toByteArray();
-        } finally {
-            if (bis != null) {
-                bis.close();
-            }
-        }
-    }
-
-    public CrtPanel getCrtPanel() {
-        return crtPanel;
+        // Defaults
+        this.horizontalDisplayed = 40;
+        this.verticalDisplayed = 25;
+        this.scanLinesPerRow = 9;
+        this.cursorStartLine = 0;
+        this.cursorStopLine = 8;
+        this.startAddress = 0x7000;
+        this.cursorPosition = 0;
+        this.pageSize = horizontalDisplayed * verticalDisplayed;
+        this.cursorEnabled = true;
+        this.cursorBlinkRate = 500;
     }
 
     @Override
     public void write(int address, int data) throws MemoryAccessException {
+        logger.info("[write] Writing CRTC address=" + address + " data=" + data);
         switch (address) {
             case REGISTER_SELECT:
                 setCurrentRegister(data);
+                break;
             case REGISTER_WRITE:
                 writeRegisterValue(data);
+                break;
             default:
                 throw new MemoryAccessException("No such address.");
         }
+
+        notifyListeners();
     }
 
     @Override
@@ -87,15 +126,80 @@ public class Crtc extends Device {
         return null;
     }
 
+    public int[] getDmaAccess() {
+        return memory.getDmaAccess();
+    }
+
     private int status() {
         return 0;
     }
 
+    public int getHorizontalDisplayed() {
+        return horizontalDisplayed;
+    }
+
+    public int getVerticalDisplayed() {
+        return verticalDisplayed;
+    }
+
+    public int getScanLinesPerRow() {
+        return scanLinesPerRow;
+    }
+
+    public int getCursorStartLine() {
+        return cursorStartLine;
+    }
+
+    public int getCursorStopLine() {
+        return cursorStopLine;
+    }
+
+    public int getCursorBlinkRate() {
+        return cursorBlinkRate;
+    }
+
+    public boolean isCursorEnabled() {
+        return cursorEnabled;
+    }
+
+    public int getStartAddress() {
+        return startAddress;
+    }
+
+    public int getCursorPosition() {
+        return cursorPosition;
+    }
+
+    public int getPageSize() {
+        return pageSize;
+    }
+
     private void setCurrentRegister(int registerNumber) {
         this.currentRegister = registerNumber;
     }
 
     private void writeRegisterValue(int data) {
+        logger.info("Writing CRTC Register #" + currentRegister + " with value " + String.format("$%02X", data));
+        switch (currentRegister) {
+            case HORIZONTAL_DISPLAYED:
+                horizontalDisplayed = data;
+                pageSize = horizontalDisplayed * verticalDisplayed;
+                break;
+            case VERTICAL_DISPLAYED:
+                verticalDisplayed = data;
+                pageSize = horizontalDisplayed * verticalDisplayed;
+                break;
+            case MODE_CONTROL:
+                // TODO: Implement multiple addressing modes.
+                break;
+            case SCAN_LINE:
+                scanLinesPerRow = data;
+                break;
+            default:
+                logger.info("Ignoring.");
+                break;
+        }
 
+        notifyListeners();
     }
 }