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Diffstat (limited to 'pokeytest/pokey.h')
| -rw-r--r-- | pokeytest/pokey.h | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/pokeytest/pokey.h b/pokeytest/pokey.h new file mode 100644 index 0000000..ee2c6e3 --- /dev/null +++ b/pokeytest/pokey.h @@ -0,0 +1,77 @@ +/*****************************************************************************/ +/* */ +/* 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 |