Create Memory.java

Emulator_Pom1/apple1/Memory.java

@@ -0,0 +1,223 @@
+/*
+ * Memory.java - memory v 0.1
+ * Copyright (C) 2000 VERHILLE Arnaud
+ * gist@wanadoo.fr
+ * http://www.chez.com/apple1/
+ * 
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA. */
+
+package apple1;
+
+import java.net.URL;
+import java.io.FileInputStream;
+import java.io.DataInputStream;
+
+/**
+ *  
+ * This is a simple Memory int[0x10000] object.
+ *
+ * @author     VERHILLE Arnaud 
+ * @created    21 octobre 2000 
+ */
+public class Memory {
+    private boolean ram8k;
+    private boolean writeInRom;
+    private boolean appletMode = false;
+    private int[] mem = new int[0x10000];
+    private Pia6820 pia;
+    private URL appletCodeBase; 
+        
+    /**
+     *  constructor for an Executable <BR> Initialise the Memory by filling it with zero 
+     *
+     * @param  pia  Pia Interface Object
+     */
+    public Memory(Pia6820 pia) {
+	reset();
+	this.pia = pia;
+	ram8k = false;
+	writeInRom = true;
+    }
+    /**
+     *  constructor for an Applet <BR> Initialise the Memory by filling it with zero 
+     *
+     * @param  pia  Pia Interface Object
+     * @param  appletCodeBase Your Applet URL
+     * @param  appletMode Must be true
+     */
+    public Memory(Pia6820 pia,URL appletCodeBase,boolean appletMode) {
+	this.appletMode = appletMode;
+	this.appletCodeBase = appletCodeBase;
+	reset();
+	this.pia = pia;
+	ram8k = false;
+	writeInRom = true;
+    }    
+    /**
+     *  Sets the Ram8k attribute of the Memory object 
+     *
+     * @param  b  The new Ram8k value 
+     */
+    public void setRam8k(boolean b) {
+	ram8k = b;
+    }    
+    /**
+     *  Sets the WriteInRom attribute of the Memory object 
+     *
+     * @param  b  The new WriteInRom value 
+     */
+    public void setWriteInRom(boolean b) {
+	writeInRom = b;
+    }
+    /**
+     *  Read a memory Address 
+     *
+     * @param  address  Range 0 to 0xFFFF 
+     * @return          It must be a byte (0 - 0xFF) 
+     */
+    public int read(int address) {
+	if (address == 0xD013) {
+	    // Video I/O DSPCR
+	    return pia.readDspCr();
+	}
+	if (address == 0xD012) {
+	    return pia.readDsp();
+	}
+	if (address == 0xD011) {
+	    // Keyboard I/O KBDCR
+	    return pia.readKbdCr();
+	}
+	if (address == 0xD010) {
+	    return pia.readKbd();
+	}
+	return mem[address];
+    }
+    /**
+     *  Write a value in a memory address 
+     *
+     * @param  address  Range 0 to 0xFFFF 
+     * @param  value    It must be a byte (0 - OxFF) 
+     */
+    public void write(int address, int value) {
+	// I/O memory Address
+	if (address == 0xD013) {
+	    // Video I/O DSPCR
+	    mem[address] = value;
+	    pia.writeDspCr(value);
+	    return;
+	}
+	if (address == 0xD012) {
+	    mem[address] = value;
+	    pia.writeDsp(value);
+	    return;
+	}
+	if (address == 0xD011) {
+	    // Keyboard I/O KBDCR
+	    mem[address] = value;
+	    pia.writeKbdCr(value);
+	    return;
+	}
+	if (address == 0xD010) {
+	    mem[address] = value;
+	    pia.writeKbd(value);
+	    return;
+	}
+	// RAM and ROM Address
+	if (address >= 0xFF00) {
+	    // Do not write in Rom ?
+	    if (!writeInRom) {
+		return;
+	    }
+	}
+	if (ram8k) {
+	    // only 8kb of Ram
+	    if (address >= 0x2000) {
+		if (address < 0xFF00) {
+		    return;
+		}
+	    }
+	}
+	mem[address] = value;
+    }
+
+    // **********************************************
+    // ************ Utility Methods  ****************
+    // **********************************************
+    /**
+     *  Reset the Memory <BR> Fill it with zero then load the bios
+     */
+    public void reset() {
+	int i;
+	for (i = 0; i < 0x10000; i++) {
+	    mem[i] = 0x00;
+	}
+	loadRom();
+    }
+    /**
+     *  Dump the Memory from start to end
+     *
+     * @param  start  int value [0x00, OxFFFF]
+     * @param  end    int value [0x00, OxFFFF]
+     * @return        Int[]
+     */
+    public int[] dumpMemory(int start, int end) {
+	int i;
+	int[] fbrut = new int[end - start + 1];
+	for (i = 0; i < (end - start + 1); i++) {
+	    fbrut[i] = (mem[start + i] & 0xFF);
+	}
+	return fbrut;
+    }
+    /**
+     *  Load the Wozniak Monitor BIOS in Memory <BR> Use Executable or Applet Functions
+     */
+    public void loadRom() {
+   
+	if (appletMode == false){ // Normal File Access
+	    String filename = System.getProperty("user.dir") + "/bios/apple1.rom";
+	    int startingAddress = 0xFF00;
+	    FileInputStream fis = null;
+	    try {
+		fis = new FileInputStream(filename);
+		int i;
+		for (i = startingAddress; i < 0x10000; i++) {
+		    mem[i] = fis.read();
+		}
+		fis.close();
+	    }
+	    catch (Exception e) {
+		System.out.println(e);
+	    } 
+	} else { // URL Applet File Access Mode
+
+	    DataInputStream fis = null;
+	    try{
+		URL u = new URL(appletCodeBase,"apple1.rom");
+		int startingAddress = 0xFF00;
+			
+		fis = new DataInputStream (u.openStream());
+		int i;
+		for (i = startingAddress; i < 0x10000; i++) {
+		    mem[i] = fis.read();
+		}
+		fis.close();
+	    } catch (Exception e) {
+		System.out.println(e);
+		System.out.println("URL Error Access in Memory.class");
+		return;
+	    }
+	}
+    }
+}