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diff --git a/apps/plugins/pacbox/wsg3.h b/apps/plugins/pacbox/wsg3.h
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+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Pacbox - a Pacman Emulator for Rockbox
+ *
+ * Based on PIE - Pacman Instructional Emulator
+ *
+ * Namco custom waveform sound generator 3 (Pacman hardware)
+ *
+ * Copyright (c) 2003,2004 Alessandro Scotti
+ * http://www.ascotti.org/
+ *
+ * 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 (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#ifndef WSG3_H
+#define WSG3_H
+
+/**
+    Namco 3-channel sound generator voice properties.    
+
+    This information is only needed by applications that want to do their own
+    sound rendering, as the playSound() function already plays and mixes all
+    three voices.
+
+    @see PacmanMachine::playSound
+*/
+struct wsg3_voice
+{
+    /** Volume (from 0 to 15) */
+    unsigned volume;
+    /** Index into the 4-bit 32-entry waveform table (0 to 7) */
+    unsigned waveform; 
+    /** Frequency */
+    unsigned frequency;
+};
+
+
+struct wsg3
+{
+    unsigned master_clock;
+    unsigned sampling_rate;
+    unsigned char sound_regs[0x20];
+    unsigned char sound_prom[32*8];
+    unsigned resample_step;
+    unsigned wave_offset[3];
+    int sound_wave_data[32*8];
+};
+
+extern struct wsg3 wsg3;
+
+/**
+    Constructor.
+
+    @param masterClock clock frequency of sound chip (in Hertz)
+
+    @see #wsg3_play_sound
+*/
+void wsg3_init(unsigned master_clock);
+
+/**
+    Sets the 256 byte PROM that contains the waveform table used by the sound chip.
+*/
+void wsg3_set_sound_prom( const unsigned char * prom );
+
+/**
+    Sets the value of the specified register.
+*/
+static inline void wsg3_set_register(unsigned reg, unsigned char value)
+    { wsg3.sound_regs[reg] = value; }
+
+/**
+    Returns the value of the specified register.
+*/
+static inline unsigned char wsg3_get_register(unsigned reg)
+    { return wsg3.sound_regs[reg]; }
+
+/**
+    Reproduces the sound that is currently being generated by the sound
+    chip into the specified buffer.
+
+    The sound chip has three independent voices that generate 8-bit signed
+    PCM audio. This function resamples the voices at the currently specified
+    sampling rate and mixes them into the output buffer. The output buffer
+    can be converted to 8-bit (signed) PCM by dividing each sample by 3 (since 
+    there are three voices) or it can be expanded to 16-bit by multiplying
+    each sample by 85 (i.e. 256 divided by 3). If necessary, it is possible
+    to approximate these values with 4 and 64 in order to use arithmetic
+    shifts that are usually faster to execute.
+
+    Note: this function does not clear the content of the output buffer before
+    mixing voices into it.
+
+    @param buf pointer to sound buffer that receives the audio samples
+    @param len length of the sound buffer
+*/
+void wsg3_play_sound(int * buf, int len);
+
+/**
+    Returns the sampling rate currently in use for rendering sound.
+*/
+static inline unsigned wsg3_get_sampling_rate(void)
+    { return wsg3.sampling_rate; }
+
+/**
+    Sets the output sampling rate for playSound().
+
+    @param samplingRate sampling rate in Hertz (samples per second)
+*/
+void wsg3_set_sampling_rate(unsigned sampling_rate);
+
+#endif /* WSG3_H */