jace/src/main/java/jace/apple2e/RAM128k.java

286 lines
11 KiB
Java

/*
* Copyright (C) 2012 Brendan Robert (BLuRry) brendan.robert@gmail.com.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*/
package jace.apple2e;
import jace.core.Card;
import jace.core.Computer;
import jace.core.PagedMemory;
import jace.core.RAM;
import jace.state.Stateful;
import java.io.IOException;
import java.io.InputStream;
/**
* Implementation of a 128k memory space and the MMU found in an Apple //e. The
* MMU behavior is mimicked by configureActiveMemory.
*
* @author Brendan Robert (BLuRry) brendan.robert@gmail.com
*/
@Stateful
abstract public class RAM128k extends RAM {
@Stateful
public PagedMemory mainMemory;
@Stateful
public PagedMemory languageCard;
@Stateful
public PagedMemory languageCard2;
public PagedMemory cPageRom;
public PagedMemory rom;
public PagedMemory blank;
public RAM128k() {
super();
mainMemory = new PagedMemory(0xc000, PagedMemory.Type.ram);
rom = new PagedMemory(0x3000, PagedMemory.Type.firmwareMain);
cPageRom = new PagedMemory(0x1000, PagedMemory.Type.slotRom);
languageCard = new PagedMemory(0x3000, PagedMemory.Type.languageCard);
languageCard2 = new PagedMemory(0x1000, PagedMemory.Type.languageCard);
activeRead = new PagedMemory(0x10000, PagedMemory.Type.ram);
activeWrite = new PagedMemory(0x10000, PagedMemory.Type.ram);
blank = new PagedMemory(0x100, PagedMemory.Type.ram);
// Format memory with FF FF 00 00 pattern
for (int i = 0; i < 0x0100; i++) {
blank.get(0)[i] = (byte) 0x0FF;
}
initMemoryPattern(mainMemory);
}
public final void initMemoryPattern(PagedMemory mem) {
// Format memory with FF FF 00 00 pattern
for (int i = 0; i < 0x0100; i++) {
for (int j = 0; j < 0x0c0; j++) {
byte use = (byte) ((i % 4) > 1 ? 0x0FF : 0x00);
mem.get(j)[i] = use;
}
}
}
/**
*
*/
@Override
public void configureActiveMemory() {
log("MMU Switches");
synchronized (this) {
// First off, set up read/write for main memory (might get changed later on)
activeRead.fillBanks(SoftSwitches.RAMRD.getState() ? getAuxMemory() : mainMemory);
activeWrite.fillBanks(SoftSwitches.RAMWRT.getState() ? getAuxMemory() : mainMemory);
// Handle language card softswitches
activeRead.fillBanks(rom);
//activeRead.fillBanks(cPageRom);
for (int i = 0x0c0; i < 0x0d0; i++) {
activeWrite.set(i, null);
}
if (SoftSwitches.LCRAM.getState()) {
if (!SoftSwitches.AUXZP.getState()) {
activeRead.fillBanks(languageCard);
if (!SoftSwitches.LCBANK1.getState()) {
activeRead.fillBanks(languageCard2);
}
} else {
activeRead.fillBanks(getAuxLanguageCard());
if (!SoftSwitches.LCBANK1.getState()) {
activeRead.fillBanks(getAuxLanguageCard2());
}
}
}
if (SoftSwitches.LCWRITE.getState()) {
if (!SoftSwitches.AUXZP.getState()) {
activeWrite.fillBanks(languageCard);
if (!SoftSwitches.LCBANK1.getState()) {
activeWrite.fillBanks(languageCard2);
}
} else {
activeWrite.fillBanks(getAuxLanguageCard());
if (!SoftSwitches.LCBANK1.getState()) {
activeWrite.fillBanks(getAuxLanguageCard2());
}
}
} else {
// Make 0xd000 - 0xffff non-writable!
for (int i = 0x0d0; i < 0x0100; i++) {
activeWrite.set(i, null);
}
}
// Handle 80STORE logic for bankswitching video ram
if (SoftSwitches._80STORE.isOn()) {
activeRead.setBanks(0x04, 0x04, 0x04,
SoftSwitches.PAGE2.isOn() ? getAuxMemory() : mainMemory);
activeWrite.setBanks(0x04, 0x04, 0x04,
SoftSwitches.PAGE2.isOn() ? getAuxMemory() : mainMemory);
if (SoftSwitches.HIRES.isOn()) {
activeRead.setBanks(0x020, 0x020, 0x020,
SoftSwitches.PAGE2.isOn() ? getAuxMemory() : mainMemory);
activeWrite.setBanks(0x020, 0x020, 0x020,
SoftSwitches.PAGE2.isOn() ? getAuxMemory() : mainMemory);
}
}
// Handle zero-page bankswitching
if (SoftSwitches.AUXZP.getState()) {
// Aux pages 0 and 1
activeRead.setBanks(0, 2, 0, getAuxMemory());
activeWrite.setBanks(0, 2, 0, getAuxMemory());
} else {
// Main pages 0 and 1
activeRead.setBanks(0, 2, 0, mainMemory);
activeWrite.setBanks(0, 2, 0, mainMemory);
}
/*
INTCXROM SLOTC3ROM C1,C2,C4-CF C3
0 0 slot rom
0 1 slot slot
1 - rom rom
*/
if (SoftSwitches.CXROM.getState()) {
// Enable C1-CF to point to rom
activeRead.setBanks(0, 0x0F, 0x0C1, cPageRom);
} else {
// Enable C1-CF to point to slots
for (int slot = 1; slot <= 7; slot++) {
Card c = getCard(slot);
if (c != null) {
// Enable card slot ROM
activeRead.setBanks(0, 1, 0x0C0 + slot, c.getCxRom());
if (getActiveSlot() == slot) {
activeRead.setBanks(0, 8, 0x0C8, c.getC8Rom());
}
} else {
// Disable card slot ROM (TODO: floating bus)
activeRead.set(0x0C0 + slot, blank.get(0));
}
}
if (getActiveSlot() == 0) {
for (int i = 0x0C8; i < 0x0D0; i++) {
activeRead.set(i, blank.get(0));
}
}
if (SoftSwitches.SLOTC3ROM.isOff()) {
// Enable C3 to point to internal ROM
activeRead.setBanks(2, 1, 0x0C3, cPageRom);
}
if (SoftSwitches.INTC8ROM.getState()) {
// Enable C8-CF to point to internal ROM
activeRead.setBanks(7, 8, 0x0C8, cPageRom);
}
}
}
// All ROM reads not intecepted will return 0xFF! (TODO: floating bus)
activeRead.set(0x0c0, blank.get(0));
}
public void log(String message) {
if (Computer.getComputer().cpu != null && Computer.getComputer().cpu.isLogEnabled()) {
String stack = "";
for (StackTraceElement e : Thread.currentThread().getStackTrace()) {
stack += e.getClassName() + "." + e.getMethodName() + "(" + e.getLineNumber() + ");";
}
Computer.getComputer().cpu.log(stack);
Computer.getComputer().cpu.log(message + ";" + SoftSwitches.RAMRD + ";" + SoftSwitches.RAMWRT + ";" + SoftSwitches.AUXZP + ";" + SoftSwitches._80STORE + ";" + SoftSwitches.HIRES + ";" + SoftSwitches.PAGE2 + ";" + SoftSwitches.LCBANK1 + ";" + SoftSwitches.LCRAM + ";" + SoftSwitches.LCWRITE);
}
}
/**
*
* @param path
* @throws java.io.IOException
*/
@Override
protected void loadRom(String path) throws IOException {
// Remap writable ram to reflect rom file structure
byte[] ignore = new byte[256];
activeWrite.set(0, ignore); // Ignore first bank of data
for (int i = 1; i < 17; i++) {
activeWrite.set(i, ignore);
}
activeWrite.setBanks(0, cPageRom.getMemory().length, 0x011, cPageRom);
activeWrite.setBanks(0, rom.getMemory().length, 0x020, rom);
//----------------------
InputStream inputRom = getClass().getClassLoader().getResourceAsStream(path);
int read = 0;
int addr = 0;
byte[] in = new byte[1024];
while (addr < 0x00FFFF && (read = inputRom.read(in)) > 0) {
for (int i = 0; i < read; i++) {
write(addr++, in[i], false, false);
}
}
// System.out.println("Finished reading rom with " + inputRom.available() + " bytes left unread!");
//dump();
configureActiveMemory();
}
/**
* @return the mainMemory
*/
public PagedMemory getMainMemory() {
return mainMemory;
}
abstract public PagedMemory getAuxVideoMemory();
abstract public PagedMemory getAuxMemory();
abstract public PagedMemory getAuxLanguageCard();
abstract public PagedMemory getAuxLanguageCard2();
/**
* @return the languageCard
*/
public PagedMemory getLanguageCard() {
return languageCard;
}
/**
* @return the languageCard2
*/
public PagedMemory getLanguageCard2() {
return languageCard2;
}
/**
* @return the cPageRom
*/
public PagedMemory getcPageRom() {
return cPageRom;
}
/**
* @return the rom
*/
public PagedMemory getRom() {
return rom;
}
void copyFrom(RAM128k currentMemory) {
// This is really quick and dirty but should be sufficient to avoid most crashes...
blank = currentMemory.blank;
cPageRom = currentMemory.cPageRom;
rom = currentMemory.rom;
listeners = currentMemory.listeners;
mainMemory = currentMemory.mainMemory;
languageCard = currentMemory.languageCard;
languageCard2 = currentMemory.languageCard2;
cards = currentMemory.cards;
activeSlot = currentMemory.activeSlot;
}
}