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/*****************************************************************************/
/* */
/* Module: POKEY Chip Simulator Includes, V1.1 */
/* Purpose: To emulate the sound generation hardware of the Atari POKEY chip.*/
/* Author: Ron Fries */
/* Date: September 22, 1996 */
/* */
/*****************************************************************************/
/* */
/* License Information and Copyright Notice */
/* ======================================== */
/* */
/* PokeySound is Copyright(c) 1996 by Ron Fries */
/* */
/* This library is free software; you can redistribute it and/or modify it */
/* under the terms of version 2 of the GNU Library General Public License */
/* as published by the Free Software Foundation. */
/* */
/* 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 Library */
/* General Public License for more details. */
/* To obtain a copy of the GNU Library General Public License, write to the */
/* Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
/* */
/* Any permitted reproduction of these routines, in whole or in part, must */
/* bear this legend. */
/* */
/*****************************************************************************/
#ifndef _POKEYSOUND_H
#define _POKEYSOUND_H
#include <stdint.h>
#define int8 int8_t
#define int16 int16_t
#define int32 int32_t
#define uint8 uint8_t
#define uint16 uint16_t
#define uint32 uint32_t
#define audf1 (0xd200 + 0x00)
#define audc1 (0xd200 + 0x01)
#define audf2 (0xd200 + 0x02)
#define audc2 (0xd200 + 0x03)
#define audf3 (0xd200 + 0x04)
#define audc3 (0xd200 + 0x05)
#define audf4 (0xd200 + 0x06)
#define audc4 (0xd200 + 0x07)
#define audctl (0xd200 + 0x08)
/* CONSTANT DEFINITIONS */
/* As an alternative to using the exact frequencies, selecting a playback
frequency that is an exact division of the main clock provides a higher
quality output due to less aliasing. For best results, a value of
1787520 MHz is used for the main clock. With this value, both the
64 kHz and 15 kHz clocks are evenly divisible. Selecting a playback
frequency that is also a division of the clock provides the best
results. The best options are FREQ_64 divided by either 2, 3, or 4.
The best selection is based on a trade off between performance and
sound quality.
Of course, using a main clock frequency that is not exact will affect
the pitch of the output. With these numbers, the pitch will be low
by 0.127%. (More than likely, an actual unit will vary by this much!) */
#define FREQ_17_EXACT 1789790 /* exact 1.79 MHz clock freq */
#define FREQ_17_APPROX 1787520 /* approximate 1.79 MHz clock freq */
void Pokey_sound_init (uint32 freq17, uint16 playback_freq);
void Update_pokey_sound (uint16 addr, uint8 val);
void Pokey_process_2 (register unsigned char *buffer, register uint16 n);
void Pokey_process (register unsigned char *buffer, register uint16 n);
#endif
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