src/hardware/innova.cpp

/*
 *  Copyright (C) 2002-2020  The DOSBox Team
 *
 *  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.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */

#include <string.h>
#include "dosbox.h"
#include "inout.h"
#include "mixer.h"
#include "pic.h"
#include "setup.h"
#include "control.h"

#include "reSID/sid.h"

#define SID_FREQ 894886

static struct {
        SID2* sid;
        Bitu rate;
        Bitu basePort;
        Bitu last_used;
        MixerChannel * chan;
} innova;

static void innova_write(Bitu port,Bitu val,Bitu iolen) {
    (void)iolen;//UNUSED
        if (!innova.last_used) {
                innova.chan->Enable(true);
        }
        innova.last_used=PIC_Ticks;

        Bitu sidPort = port-innova.basePort;
        innova.sid->write((reg8)sidPort, (reg8)val);
}

static Bitu innova_read(Bitu port,Bitu iolen) {
    (void)iolen;//UNUSED
        Bitu sidPort = port-innova.basePort;
        return innova.sid->read((reg8)sidPort);
}


static void INNOVA_CallBack(Bitu len) {
        if (!len) return;

        cycle_count delta_t = (cycle_count)(SID_FREQ*len/innova.rate);
        short* buffer = (short*)MixTemp;
        Bitu bufindex = 0;

        while(delta_t && bufindex != len) {
                bufindex += (Bitu)innova.sid->clock(delta_t, buffer+bufindex, (int)(len-bufindex));
        }
        innova.chan->AddSamples_m16(len, buffer);

        if (innova.last_used+5000<PIC_Ticks) {
                innova.last_used=0;
                innova.chan->Enable(false);
        }
}

class INNOVA: public Module_base {
private:
        IO_ReadHandleObject ReadHandler;
        IO_WriteHandleObject WriteHandler;
        MixerObject MixerChan;
public:
        INNOVA(Section* configuration):Module_base(configuration) {
                Section_prop * section=static_cast<Section_prop *>(configuration);
                if(!section->Get_bool("innova")) return;
                innova.rate = (unsigned int)section->Get_int("samplerate");
                innova.basePort = (unsigned int)section->Get_hex("sidbase");
                sampling_method method = SAMPLE_FAST;
                int m = section->Get_int("quality");
                switch(m) {
                case 1: method = SAMPLE_INTERPOLATE; break;
                case 2: method = SAMPLE_RESAMPLE_FAST; break;
                case 3: method = SAMPLE_RESAMPLE_INTERPOLATE; break;
                }

                LOG_MSG("INNOVA:Initializing Innovation SSI-2001 (SID) emulation...");

                WriteHandler.Install(innova.basePort,innova_write,IO_MB,0x20);
                ReadHandler.Install(innova.basePort,innova_read,IO_MB,0x20);
        
                innova.chan=MixerChan.Install(&INNOVA_CallBack,innova.rate,"INNOVA");

                innova.sid = new SID2;
                innova.sid->set_chip_model(MOS6581);
                innova.sid->enable_filter(true);
                innova.sid->enable_external_filter(true);
                innova.sid->set_sampling_parameters(SID_FREQ, method, (double)innova.rate, -1, 0.97);

                innova.last_used=0;

                LOG_MSG("INNOVA:... finished.");
        }
        ~INNOVA(){
                delete innova.sid;
        }
};

static INNOVA* test = NULL;

static void INNOVA_ShutDown(Section* sec){
    (void)sec;//UNUSED
    if (test != NULL) {
        delete test;
        test = NULL;
    }
}

void INNOVA_OnReset(Section *sec) {
    (void)sec;//UNUSED
        if (test == NULL && !IS_PC98_ARCH) {
                LOG(LOG_MISC,LOG_DEBUG)("Allocating Innova emulation");
                test = new INNOVA(control->GetSection("innova"));
        }
}

void INNOVA_Init() {
        LOG(LOG_MISC,LOG_DEBUG)("Initializing INNOVA emulation");

        AddExitFunction(AddExitFunctionFuncPair(INNOVA_ShutDown),true);
        AddVMEventFunction(VM_EVENT_RESET,AddVMEventFunctionFuncPair(INNOVA_OnReset));
}