/**
* Handle word read access from IO memory.
*/
uae_u32 IoMem_wget(uaecptr addr)
{
Uint32 idx;
Uint16 val;
/* Check if access is made by a new instruction or by the same instruction doing multiple word accesses */
if ( IoAccessInstrPrevClock == CyclesGlobalClockCounter )
IoAccessInstrCount++; /* Same instruction, increase access count */
else
{
IoAccessInstrPrevClock = CyclesGlobalClockCounter;
if ( ( table68k[ M68000_CurrentOpcode ].size == 1 )
&& ( OpcodeFamily != i_MVMEL ) && ( OpcodeFamily != i_MVMLE ) )
IoAccessInstrCount = 0; /* Instruction size is word and not a movem : no multiple accesses */
else
IoAccessInstrCount = 1; /* 1st access of a long or movem.w */
}
addr &= 0x00ffffff; /* Use a 24 bit address */
if (addr < 0xff8000 || !regs.s)
{
/* invalid memory addressing --> bus error */
M68000_BusError(addr, BUS_ERROR_READ, BUS_ERROR_SIZE_WORD, BUS_ERROR_ACCESS_DATA);
return -1;
}
if (addr > 0xfffffe)
{
fprintf(stderr, "Illegal IO memory access: IoMem_wget($%x)\n", addr);
return -1;
}
IoAccessBaseAddress = addr; /* Store for exception frame */
nIoMemAccessSize = SIZE_WORD;
nBusErrorAccesses = 0;
idx = addr - 0xff8000;
IoAccessCurrentAddress = addr;
pInterceptReadTable[idx](); /* Call 1st handler */
if (pInterceptReadTable[idx+1] != pInterceptReadTable[idx])
{
IoAccessCurrentAddress = addr + 1;
pInterceptReadTable[idx+1](); /* Call 2nd handler */
}
/* Check if we completely read from a bus-error region */
if (nBusErrorAccesses == 2)
{
M68000_BusError(addr, BUS_ERROR_READ, BUS_ERROR_SIZE_WORD, BUS_ERROR_ACCESS_DATA);
return -1;
}
val = IoMem_ReadWord(addr);
LOG_TRACE(TRACE_IOMEM_RD, "IO read.w $%06x = $%04x pc=%x\n", addr, val, M68000_GetPC());
return val;
}
/**
* Write word to sound control register (0xff8900).
*
* FIXME: add Falcon specific handler here...
*/
void DmaSnd_SoundControl_WriteWord(void)
{
Uint16 nNewSndCtrl;
HATARI_TRACE(HATARI_TRACE_DMASND, "DMA snd control write: 0x%04x\n", IoMem_ReadWord(0xff8900));
nNewSndCtrl = IoMem_ReadWord(0xff8900) & 3;
if (!(nDmaSoundControl & DMASNDCTRL_PLAY) && (nNewSndCtrl & DMASNDCTRL_PLAY))
{
//fprintf(stderr, "Turning on DMA sound emulation.\n");
DmaSnd_StartNewFrame();
}
else if ((nDmaSoundControl & DMASNDCTRL_PLAY) && !(nNewSndCtrl & DMASNDCTRL_PLAY))
{
//fprintf(stderr, "Turning off DMA sound emulation.\n");
}
nDmaSoundControl = nNewSndCtrl;
}
/**
* Handle word read access from IO memory.
*/
uae_u32 IoMem_wget(uaecptr addr)
{
Uint32 idx;
Uint16 val;
addr &= 0x00ffffff; /* Use a 24 bit address */
if (addr < 0xff8000 || !regs.s)
{
/* invalid memory addressing --> bus error */
M68000_BusError(addr, BUS_ERROR_READ);
return -1;
}
if (addr > 0xfffffe)
{
fprintf(stderr, "Illegal IO memory access: IoMem_wget($%x)\n", addr);
return -1;
}
IoAccessBaseAddress = addr; /* Store for exception frame */
nIoMemAccessSize = SIZE_WORD;
nBusErrorAccesses = 0;
idx = addr - 0xff8000;
IoAccessCurrentAddress = addr;
pInterceptReadTable[idx](); /* Call 1st handler */
if (pInterceptReadTable[idx+1] != pInterceptReadTable[idx])
{
IoAccessCurrentAddress = addr + 1;
pInterceptReadTable[idx+1](); /* Call 2nd handler */
}
/* Check if we completely read from a bus-error region */
if (nBusErrorAccesses == 2)
{
M68000_BusError(addr, BUS_ERROR_READ);
return -1;
}
val = IoMem_ReadWord(addr);
LOG_TRACE(TRACE_IOMEM_RD, "IO read.w $%06x = $%04x\n", addr, val);
return val;
}
/**
* Handle word read access from IO memory.
*/
uae_u32 IoMem_wget(uaecptr addr)
{
Uint32 idx;
Uint16 val;
if ((addr & IO_SEG_MASK) >= IO_SIZE)
{
/* invalid memory addressing --> bus error */
M68000_BusError(addr, BUS_ERROR_READ);
return -1;
}
IoAccessBaseAddress = addr; /* Store for exception frame */
nIoMemAccessSize = SIZE_WORD;
nBusErrorAccesses = 0;
idx = addr & IO_SEG_MASK;
IoAccessCurrentAddress = addr;
pInterceptReadTable[idx](); /* Call 1st handler */
if (pInterceptReadTable[idx+1] != pInterceptReadTable[idx])
{
IoAccessCurrentAddress = addr + 1;
pInterceptReadTable[idx+1](); /* Call 2nd handler */
}
/* Check if we completely read from a bus-error region */
if (nBusErrorAccesses == 2)
{
M68000_BusError(addr, BUS_ERROR_READ);
return -1;
}
val = IoMem_ReadWord(addr);
LOG_TRACE(TRACE_IOMEM_RD, "IO read.w $%06x = $%04x\n", addr, val);
return val;
}
/**
* Mix DMA sound sample with the normal PSG sound samples.
*/
void DmaSnd_GenerateSamples(int nMixBufIdx, int nSamplesToGenerate)
{
double FreqRatio;
int i;
int nBufIdx;
Sint8 *pFrameStart;
if (ConfigureParams.System.nMachineType == MACHINE_FALCON
&& (IoMem_ReadWord(0xff8932) & 0x6000) == 0x2000)
{
DmaSnd_GenerateDspSamples(nMixBufIdx, nSamplesToGenerate);
return;
}
if (!(nDmaSoundControl & DMASNDCTRL_PLAY))
return;
pFrameStart = (Sint8 *)&STRam[nFrameStartAddr];
FreqRatio = DmaSnd_DetectSampleRate() / (double)nAudioFrequency;
if (ConfigureParams.System.nMachineType == MACHINE_FALCON
&& (nDmaSoundMode & DMASNDMODE_16BITSTEREO))
{
/* Stereo 16-bit */
FreqRatio *= 4.0;
for (i = 0; i < nSamplesToGenerate; i++)
{
nBufIdx = (nMixBufIdx + i) % MIXBUFFER_SIZE;
MixBuffer[nBufIdx][0] = ((int)MixBuffer[nBufIdx][0]
+ (int)(*(Sint16*)&pFrameStart[((int)FrameCounter)&~1])) / 2;
MixBuffer[nBufIdx][1] = ((int)MixBuffer[nBufIdx][1]
+ (int)(*(Sint16*)&pFrameStart[(((int)FrameCounter)&~1)+2])) / 2;
FrameCounter += FreqRatio;
if (DmaSnd_CheckForEndOfFrame(FrameCounter))
break;
}
}
else if (nDmaSoundMode & DMASNDMODE_MONO) /* 8-bit stereo or mono? */
{
/* Mono 8-bit */
for (i = 0; i < nSamplesToGenerate; i++)
{
nBufIdx = (nMixBufIdx + i) % MIXBUFFER_SIZE;
MixBuffer[nBufIdx][0] = MixBuffer[nBufIdx][1] =
((int)MixBuffer[nBufIdx][0] + (((int)pFrameStart[(int)FrameCounter]) << 8)) / 2;
FrameCounter += FreqRatio;
if (DmaSnd_CheckForEndOfFrame(FrameCounter))
break;
}
}
else
{
/* Stereo 8-bit */
FreqRatio *= 2.0;
for (i = 0; i < nSamplesToGenerate; i++)
{
nBufIdx = (nMixBufIdx + i) % MIXBUFFER_SIZE;
MixBuffer[nBufIdx][0] = ((int)MixBuffer[nBufIdx][0]
+ (((int)pFrameStart[((int)FrameCounter)&~1]) << 8)) / 2;
MixBuffer[nBufIdx][1] = ((int)MixBuffer[nBufIdx][1]
+ (((int)pFrameStart[(((int)FrameCounter)&~1)+1]) << 8)) / 2;
FrameCounter += FreqRatio;
if (DmaSnd_CheckForEndOfFrame(FrameCounter))
break;
}
}
}
