TMS9919Consts.java

/*
  TMS9919Consts.java

  (c) 2011-2013 Edward Swartz

  All rights reserved. This program and the accompanying materials
  are made available under the terms of the Eclipse Public License v1.0
  which accompanies this distribution, and is available at
  http://www.eclipse.org/legal/epl-v10.html
 */
package v9t9.common.sound;

/**
 * @author ejs
 *
 */
public class TMS9919Consts {
	public static final String GROUP_NAME = "TMS 9919";

	/** 
	 * This is the offset in a tone or noise register bank for
	 * the frequency period of the voice (inversely related
	 * to the actual frequency by 3.579545 MHz / 32 / period).
	 */
	final public static int REG_OFFS_FREQUENCY_PERIOD = 0;
	/** 
	 * This is the offset in a tone or noise register bank for
	 * the attenuation of the voice, which affects volume in 
	 * that 15 = silence and 0 = loudest.
	 * 
	 */
	final public static int REG_OFFS_ATTENUATION = 1;
	/** 
	 * This is the offset in a noise register bank that
	 * controls its type (NOISE_FEEDBACK_MASK) and its frequency
	 * (NOISE_PERIOD_MASK).
	 * 
	 */
	final public static int REG_OFFS_NOISE_CONTROL = 0;
	
	/** 
	 * This is the offset in the audio gate register bank for
	 * the state of the audio gate (0=off, 1=on) 
	 */
	final public static int REG_OFFS_AUDIO_GATE = 0;
	
	final public static int REG_COUNT_TONE = 2;
	final public static int REG_COUNT_NOISE = 2;
	final public static int REG_COUNT_AUDIO_GATE = 1;

	/**
	 *	Masks for the noise control register
	 */
	public final static int NOISE_FEEDBACK_PERIODIC = 0,
		NOISE_FEEDBACK_WHITE = 0x4,
		NOISE_FEEDBACK_MASK = 0x4
	;

	/**
	 *	Masks for the noise control register
	 **/
	public final static int NOISE_PERIOD_FIXED_0 = 0,
		NOISE_PERIOD_FIXED_1 = 1,
		NOISE_PERIOD_FIXED_2 = 2,
		NOISE_PERIOD_VARIABLE = 3,
		NOISE_PERIOD_MASK = 0x3;
	;
	

	public static final int NOISE_DIVISORS[] = 
	{
		16,
		32, 
		64, 
		0 						/* determined by VOICE_TONE_2 */
	};

	public static final int CHIP_CLOCK = 3579545;
}