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VARCem/src/sound/snd_dbopl.cpp

256 lines
7.4 KiB
C++

/*
* VARCem Virtual ARchaeological Computer EMulator.
* An emulator of (mostly) x86-based PC systems and devices,
* using the ISA,EISA,VLB,MCA and PCI system buses, roughly
* spanning the era between 1981 and 1995.
*
* This file is part of the VARCem Project.
*
* DOSbox OPL emulation.
*
* NOTE: See MSC_ macros for allocation on stack. --FvK
*
* Version: @(#)snd_dbopl.cpp 1.0.6 2018/04/25
*
* Authors: Fred N. van Kempen, <decwiz@yahoo.com>
* Miran Grca, <mgrca8@gmail.com>
* TheCollector1995, <mariogplayer@gmail.com>
* Sarah Walker, <tommowalker@tommowalker.co.uk>
*
* Copyright 2017,2018 Fred N. van Kempen.
* Copyright 2016-2018 Miran Grca.
* Copyright 2008-2018 Sarah Walker.
*
* 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 program 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
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the:
*
* Free Software Foundation, Inc.
* 59 Temple Place - Suite 330
* Boston, MA 02111-1307
* USA.
*/
#ifdef _MSC_VER
/* for malloc() and printing of the related error message with pclog() */
# include <stdio.h>
# include <stdlib.h>
# include <stdint.h>
# include "../emu.h"
#endif
#include "dbopl.h"
#include "nukedopl.h"
#include "snd_dbopl.h"
static struct
{
DBOPL::Chip chip;
struct opl3_chip opl3chip;
int addr;
int timer[2];
uint8_t timer_ctrl;
uint8_t status_mask;
uint8_t status;
int is_opl3;
void (*timer_callback)(void *param, int timer, int64_t period);
void *timer_param;
} opl[2];
enum
{
STATUS_TIMER_1 = 0x40,
STATUS_TIMER_2 = 0x20,
STATUS_TIMER_ALL = 0x80
};
enum
{
CTRL_IRQ_RESET = 0x80,
CTRL_TIMER1_MASK = 0x40,
CTRL_TIMER2_MASK = 0x20,
CTRL_TIMER2_CTRL = 0x02,
CTRL_TIMER1_CTRL = 0x01
};
void opl_init(void (*timer_callback)(void *param, int timer, int64_t period), void *timer_param, int nr, int is_opl3)
{
if (!is_opl3 || !opl3_type)
{
DBOPL::InitTables();
opl[nr].chip.Setup(48000, is_opl3);
opl[nr].timer_callback = timer_callback;
opl[nr].timer_param = timer_param;
opl[nr].is_opl3 = is_opl3;
}
else
{
OPL3_Reset(&opl[nr].opl3chip, 48000);
opl[nr].timer_callback = timer_callback;
opl[nr].timer_param = timer_param;
opl[nr].is_opl3 = is_opl3;
}
}
void opl_status_update(int nr)
{
if (opl[nr].status & (STATUS_TIMER_1 | STATUS_TIMER_2) & opl[nr].status_mask)
opl[nr].status |= STATUS_TIMER_ALL;
else
opl[nr].status &= ~STATUS_TIMER_ALL;
}
void opl_timer_over(int nr, int timer)
{
if (!timer)
{
opl[nr].status |= STATUS_TIMER_1;
opl[nr].timer_callback(opl[nr].timer_param, 0, opl[nr].timer[0] * 4);
}
else
{
opl[nr].status |= STATUS_TIMER_2;
opl[nr].timer_callback(opl[nr].timer_param, 1, opl[nr].timer[1] * 16);
}
opl_status_update(nr);
}
void opl_write(int nr, uint16_t addr, uint8_t val)
{
if (!(addr & 1))
{
if (!opl[nr].is_opl3 || !opl3_type)
opl[nr].addr = (int)opl[nr].chip.WriteAddr(addr, val) & (opl[nr].is_opl3 ? 0x1ff : 0xff);
else
opl[nr].addr = (int)OPL3_WriteAddr(&opl[nr].opl3chip, addr, val) & 0x1ff;
}
else
{
if (!opl[nr].is_opl3 || !opl3_type)
opl[nr].chip.WriteReg(opl[nr].addr, val);
else
OPL3_WriteReg(&opl[nr].opl3chip, opl[nr].addr, val);
switch (opl[nr].addr)
{
case 0x02: /*Timer 1*/
opl[nr].timer[0] = 256 - val;
break;
case 0x03: /*Timer 2*/
opl[nr].timer[1] = 256 - val;
break;
case 0x04: /*Timer control*/
if (val & CTRL_IRQ_RESET) /*IRQ reset*/
{
opl[nr].status &= ~(STATUS_TIMER_1 | STATUS_TIMER_2);
opl_status_update(nr);
return;
}
if ((val ^ opl[nr].timer_ctrl) & CTRL_TIMER1_CTRL)
{
if (val & CTRL_TIMER1_CTRL)
opl[nr].timer_callback(opl[nr].timer_param, 0, opl[nr].timer[0] * 4);
else
opl[nr].timer_callback(opl[nr].timer_param, 0, 0);
}
if ((val ^ opl[nr].timer_ctrl) & CTRL_TIMER2_CTRL)
{
if (val & CTRL_TIMER2_CTRL)
opl[nr].timer_callback(opl[nr].timer_param, 1, opl[nr].timer[1] * 16);
else
opl[nr].timer_callback(opl[nr].timer_param, 1, 0);
}
opl[nr].status_mask = (~val & (CTRL_TIMER1_MASK | CTRL_TIMER2_MASK)) | 0x80;
opl[nr].timer_ctrl = val;
break;
}
}
}
uint8_t opl_read(int nr, uint16_t addr)
{
if (!(addr & 1))
{
return (opl[nr].status & opl[nr].status_mask) | (opl[nr].is_opl3 ? 0 : 0x06);
}
return opl[nr].is_opl3 ? 0 : 0xff;
}
void opl2_update(int nr, int16_t *buffer, int samples)
{
#ifdef _MSC_VER
static Bit32s *buffer_32 = NULL;
static Bit32u buffer_sz = 0;
#endif
int c;
#ifdef _MSC_VER
/* TODO: Fix this to use a static buffer */
if (samples > 512*1024)
{
pclog("opl2_update: possible stack overflow detected. sample count was %d", samples);
return;
}
if ((sizeof(Bit32s) * samples) > buffer_sz) {
if (buffer_32 != NULL)
free(buffer_32);
buffer_sz = sizeof(Bit32s) * samples;
buffer_32 = (Bit32s *)malloc(buffer_sz);
}
#else
Bit32s buffer_32[samples];
#endif
opl[nr].chip.GenerateBlock2(samples, buffer_32);
for (c = 0; c < samples; c++)
buffer[c*2] = (int16_t)buffer_32[c];
}
void opl3_update(int nr, int16_t *buffer, int samples)
{
#ifdef _MSC_VER
static Bit32s *buffer_32 = NULL;
static Bit32u buffer_sz = 0;
#endif
int c;
#ifdef _MSC_VER
/* TODO: Fix this to use a static buffer */
if (samples > 512 * 1024)
{
pclog("opl2_update: possible stack overflow detected. sample count was %d", samples);
return;
}
if ((sizeof(Bit32s) * samples * 2) > buffer_sz) {
if (buffer_32 != NULL)
free(buffer_32);
buffer_sz = sizeof(Bit32s) * samples * 2;
buffer_32 = (Bit32s *)malloc(buffer_sz);
}
#else
Bit32s buffer_32[samples*2];
#endif
if (opl3_type)
{
OPL3_GenerateStream(&opl[nr].opl3chip, buffer, samples);
}
else
{
opl[nr].chip.GenerateBlock3(samples, buffer_32);
for (c = 0; c < samples*2; c++)
buffer[c] = (int16_t)buffer_32[c];
}
}