org.evilco.emulator.extension.chip8.Chip8Emulator.java Source code

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Here is the source code for org.evilco.emulator.extension.chip8.Chip8Emulator.java

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/*
 * Copyright (C) 2014 Johannes Donath <johannesd@evil-co.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.evilco.emulator.extension.chip8;

import io.netty.buffer.ByteBuf;
import lombok.AccessLevel;
import lombok.Getter;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.evilco.emulator.core.IEmulator;
import org.evilco.emulator.core.error.InvalidRomSizeException;
import org.evilco.emulator.core.error.RomException;
import org.evilco.emulator.core.error.RomLoaderException;
import org.evilco.emulator.core.graphic.matrix.MonochromeMatrixScreen;
import org.evilco.emulator.core.memory.error.MemoryException;
import org.evilco.emulator.extension.chip8.memory.Chip8Memory;
import org.evilco.emulator.extension.chip8.processor.Chip8Processor;

/**
 * @author Johannes Donath <johannesd@evil-co.com>
 * @copyright Copyright (C) 2014 Evil-Co <http://www.evil-co.com>
 */
public class Chip8Emulator implements IEmulator {

    /**
     * Stores the internal logger.
     */
    @Getter(AccessLevel.PROTECTED)
    private static Logger logger = LogManager.getLogger(Chip8Emulator.class);

    /**
     * Stores the emulator memory.
     */
    @Getter
    private final Chip8Memory memory;

    /**
     * Stores the emulator processor.
     */
    @Getter
    private final Chip8Processor processor;

    /**
     * Stores the emulator screen.
     */
    @Getter
    private final MonochromeMatrixScreen screen;

    /**
     * Constructs a new Code8Emulator instance.
     */
    public Chip8Emulator() {
        this.memory = new Chip8Memory();
        this.screen = new MonochromeMatrixScreen(((short) 64), ((short) 32));
        this.processor = new Chip8Processor(this);
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public void load(ByteBuf romBuffer) throws RomException {
        getLogger().debug("ROM contains " + romBuffer.readableBytes() + " bytes of data.");

        // copy ROM to memory
        try {
            long index = 0x200;

            while ((romBuffer.readableBytes() > 0 && this.memory.isValidAddress((index)))) {
                this.memory.set(index, romBuffer.readUnsignedByte());
                index++;
            }
        } catch (MemoryException ex) {
            throw new RomLoaderException(ex);
        }

        // verify
        if (romBuffer.readableBytes() > 0)
            throw new InvalidRomSizeException(
                    "Found an extra of " + romBuffer.readableBytes() + " bytes at the end of ROM file.");
    }
}