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Support Mockingboard/Phasor when polling IFR.Timer1 (#496)
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* Support precise AY8910 sound-buffer filling when polling 6522 IFR.Timer1 (ACR=Free Running mode)
  - same as if using 6522 IER.Timer1 interrupt
* Support 6522's Timer2 and some code refactoring
* Bump version: 1.26.3.4
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@tomcw
tomcw committed Oct 24, 2017
1 parent 49465d0 commit 66321fe
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Showing 3 changed files with 106 additions and 53 deletions.
8 changes: 4 additions & 4 deletions resource/Applewin.rc
View file
Expand Up @@ -252,8 +252,8 @@ DISK_ICON ICON "DISK.ICO"
//

VS_VERSION_INFO VERSIONINFO
FILEVERSION 1,26,3,2
PRODUCTVERSION 1,26,3,2
FILEVERSION 1,26,3,4
PRODUCTVERSION 1,26,3,4
FILEFLAGSMASK 0x3fL
#ifdef _DEBUG
FILEFLAGS 0x1L
Expand All @@ -271,12 +271,12 @@ BEGIN
VALUE "Comments", "https://github.com/AppleWin"
VALUE "CompanyName", "AppleWin"
VALUE "FileDescription", "Apple //e Emulator for Windows"
VALUE "FileVersion", "1, 26, 3, 2"
VALUE "FileVersion", "1, 26, 3, 4"
VALUE "InternalName", "APPLEWIN"
VALUE "LegalCopyright", " 1994-2017 Michael O'Brien, Oliver Schmidt, Tom Charlesworth, Michael Pohoreski, Nick Westgate, Linards Ticmanis"
VALUE "OriginalFilename", "APPLEWIN.EXE"
VALUE "ProductName", "Apple //e Emulator"
VALUE "ProductVersion", "1, 26, 3, 2"
VALUE "ProductVersion", "1, 26, 3, 4"
END
END
BLOCK "VarFileInfo"
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150 changes: 102 additions & 48 deletions source/Mockingboard.cpp
View file
Expand Up @@ -153,8 +153,8 @@ static SY6522_AY8910 g_MB[NUM_AY8910];

// Timer vars
static ULONG g_n6522TimerPeriod = 0;
static const UINT TIMERDEVICE_INVALID = -1;
static UINT g_nMBTimerDevice = TIMERDEVICE_INVALID; // SY6522 device# which is generating timer IRQ
static const UINT kTIMERDEVICE_INVALID = -1;
static UINT g_nMBTimerDevice = kTIMERDEVICE_INVALID; // SY6522 device# which is generating timer IRQ
static UINT64 g_uLastCumulativeCycles = 0;

// SSI263 vars:
Expand Down Expand Up @@ -204,13 +204,12 @@ static DWORD g_dwMaxPhonemeLen = 0;
// When 6522 IRQ is *not* active use 60Hz update freq for MB voices
static const double g_f6522TimerPeriod_NoIRQ = CLK_6502 / 60.0; // Constant whatever the CLK is set to

static bool g_bMBTimerIrqActive = false;

//---------------------------------------------------------------------------

// Forward refs:
static DWORD WINAPI SSI263Thread(LPVOID);
static void Votrax_Write(BYTE nDevice, BYTE nValue);
static double MB_GetFramePeriod(void);

//---------------------------------------------------------------------------

Expand All @@ -221,10 +220,10 @@ static void StartTimer1(SY6522_AY8910* pMB)
// 6522 CLK runs at same speed as 6502 CLK
g_n6522TimerPeriod = pMB->sy6522.TIMER1_LATCH.w;

if (pMB->sy6522.IER & IxR_TIMER1)
g_bMBTimerIrqActive = true;

g_nMBTimerDevice = pMB->nAY8910Number;
if (pMB->sy6522.IER & IxR_TIMER1) // Using 6522 interrupt
g_nMBTimerDevice = pMB->nAY8910Number;
else if (pMB->sy6522.ACR & RM_FREERUNNING) // Polling 6522 IFR
g_nMBTimerDevice = pMB->nAY8910Number;
}

// The assumption was that timer1 was only active if IER.TIMER1=1
Expand All @@ -239,18 +238,28 @@ static void StartTimer1_LoadStateV1(SY6522_AY8910* pMB)
// 6522 CLK runs at same speed as 6502 CLK
g_n6522TimerPeriod = pMB->sy6522.TIMER1_LATCH.w;

g_bMBTimerIrqActive = true;

g_nMBTimerDevice = pMB->nAY8910Number;
}

//-----------------------------------------------------------------------------

static void StopTimer1(SY6522_AY8910* pMB)
{
pMB->bTimer1Active = false;
g_bMBTimerIrqActive = false;
g_nMBTimerDevice = TIMERDEVICE_INVALID;
g_nMBTimerDevice = kTIMERDEVICE_INVALID;
}

//-----------------------------------------------------------------------------

static void StartTimer2(SY6522_AY8910* pMB)
{
pMB->bTimer2Active = true;

// NB. Can't mimic StartTimer1() as that would stomp on global state
// TODO: Switch to per-device state
}

static void StopTimer2(SY6522_AY8910* pMB)
{
pMB->bTimer2Active = false;
}

//-----------------------------------------------------------------------------
Expand All @@ -259,8 +268,8 @@ static void ResetSY6522(SY6522_AY8910* pMB)
{
memset(&pMB->sy6522,0,sizeof(SY6522));

if (pMB->bTimer1Active)
StopTimer1(pMB);
StopTimer1(pMB);
StopTimer2(pMB);

pMB->nAYCurrentRegister = 0;
}
Expand All @@ -272,7 +281,7 @@ static void AY8910_Write(BYTE nDevice, BYTE nReg, BYTE nValue, BYTE nAYDevice)
g_bMB_RegAccessedFlag = true;
SY6522_AY8910* pMB = &g_MB[nDevice];

if((nValue & 4) == 0)
if ((nValue & 4) == 0)
{
// RESET: Reset AY8910 only
AY8910_reset(nDevice+2*nAYDevice);
Expand All @@ -287,7 +296,7 @@ static void AY8910_Write(BYTE nDevice, BYTE nReg, BYTE nValue, BYTE nAYDevice)
int nAYFunc = (nBDIR<<2) | (nBC2<<1) | nBC1;
enum {AY_NOP0, AY_NOP1, AY_INACTIVE, AY_READ, AY_NOP4, AY_NOP5, AY_WRITE, AY_LATCH};

switch(nAYFunc)
switch (nAYFunc)
{
case AY_INACTIVE: // 4: INACTIVE
break;
Expand All @@ -312,17 +321,20 @@ static void AY8910_Write(BYTE nDevice, BYTE nReg, BYTE nValue, BYTE nAYDevice)
}
}

// TODO: Fix data-race: main thread & SSI263Thread accessing IFR
// . extend this func to take an or_mask & and_mask
// . then do the mods inside a critical section
static void UpdateIFR(SY6522_AY8910* pMB)
{
pMB->sy6522.IFR &= 0x7F;

if(pMB->sy6522.IFR & pMB->sy6522.IER & 0x7F)
if (pMB->sy6522.IFR & pMB->sy6522.IER & 0x7F)
pMB->sy6522.IFR |= 0x80;

// Now update the IRQ signal from all 6522s
// . OR-sum of all active TIMER1, TIMER2 & SPEECH sources (from all 6522s)
UINT bIRQ = 0;
for(UINT i=0; i<NUM_SY6522; i++)
for (UINT i=0; i<NUM_SY6522; i++)
bIRQ |= g_MB[i].sy6522.IFR & 0x80;

// NB. Mockingboard generates IRQ on both 6522s:
Expand Down Expand Up @@ -419,6 +431,8 @@ static void SY6522_Write(BYTE nDevice, BYTE nReg, BYTE nValue)

pMB->sy6522.TIMER2_LATCH.h = nValue;
pMB->sy6522.TIMER2_COUNTER.w = pMB->sy6522.TIMER2_LATCH.w;

StartTimer2(pMB);
break;
case 0x0a: // SERIAL_SHIFT
break;
Expand All @@ -444,23 +458,26 @@ static void SY6522_Write(BYTE nDevice, BYTE nReg, BYTE nValue)
pMB->sy6522.IER &= nValue;
UpdateIFR(pMB);

// Check if timer has been disabled.
if(pMB->sy6522.IER & IxR_TIMER1)
break;
// Check if active timer has been disabled:
if (((pMB->sy6522.IER & IxR_TIMER1) == 0) && pMB->bTimer1Active)
StopTimer1(pMB);

if (pMB->bTimer1Active == false)
break;

// Stop timer
StopTimer1(pMB);
if (((pMB->sy6522.IER & IxR_TIMER2) == 0) && pMB->bTimer2Active)
StopTimer2(pMB);
}
else
{
// Set those bits which are set in the lower 7 bits.
nValue &= 0x7F;
pMB->sy6522.IER |= nValue;
UpdateIFR(pMB);
StartTimer1(pMB);

// Check if active timer changed from non-interrupt (polling IFR) to interrupt:
if ((pMB->sy6522.IER & IxR_TIMER1) && pMB->bTimer1Active)
StartTimer1(pMB);

if ((pMB->sy6522.IER & IxR_TIMER2) && pMB->bTimer2Active)
StartTimer2(pMB);
}
break;
case 0x0f: // ORA_NO_HS
Expand Down Expand Up @@ -742,6 +759,9 @@ static void Votrax_Write(BYTE nDevice, BYTE nValue)

//===========================================================================

// Called by:
// . MB_UpdateCycles() - when g_nMBTimerDevice == {0,1,2,3}
// . MB_EndOfVideoFrame() - when g_nMBTimerDevice == kTIMERDEVICE_INVALID
static void MB_Update()
{
//char szDbg[200];
Expand Down Expand Up @@ -1408,7 +1428,7 @@ void MB_Destroy()
static void ResetState()
{
g_n6522TimerPeriod = 0;
g_nMBTimerDevice = TIMERDEVICE_INVALID;
g_nMBTimerDevice = kTIMERDEVICE_INVALID;
g_uLastCumulativeCycles = 0;

g_nSSI263Device = 0;
Expand Down Expand Up @@ -1650,10 +1670,10 @@ void MB_StartOfCpuExecute()
// Called by ContinueExecution() at the end of every video frame
void MB_EndOfVideoFrame()
{
if(g_SoundcardType == CT_Empty)
if (g_SoundcardType == CT_Empty)
return;

if(!g_bMBTimerIrqActive)
if (g_nMBTimerDevice == kTIMERDEVICE_INVALID)
MB_Update();
}

Expand Down Expand Up @@ -1688,11 +1708,28 @@ void MB_UpdateCycles(ULONG uExecutedCycles)
bool bTimer1Underflow = (!(OldTimer1 & 0x8000) && (pMB->sy6522.TIMER1_COUNTER.w & 0x8000));
bool bTimer2Underflow = (!(OldTimer2 & 0x8000) && (pMB->sy6522.TIMER2_COUNTER.w & 0x8000));

if ( bTimer1Underflow && (g_nMBTimerDevice == i) )
if (!pMB->bTimer1Active && bTimer1Underflow)
{
if ( (g_nMBTimerDevice == kTIMERDEVICE_INVALID) // StopTimer1() has been called
&& (pMB->sy6522.IFR & IxR_TIMER1) // Counter underflowed
&& ((pMB->sy6522.ACR & RUNMODE) == RM_ONESHOT) ) // One-shot mode
{
// Fix for Willy Byte - need to confirm that 6522 really does this!
// . It never accesses IER/IFR/TIMER1 regs to clear IRQ
pMB->sy6522.IFR &= ~IxR_TIMER1; // Deassert the TIMER IRQ
UpdateIFR(pMB);
}
}

if (pMB->bTimer1Active && bTimer1Underflow)
{
pMB->sy6522.IFR |= IxR_TIMER1;
UpdateIFR(pMB);

// Do MB_Update() before StopTimer1()
if (g_nMBTimerDevice == i)
MB_Update();

if((pMB->sy6522.ACR & RUNMODE) == RM_ONESHOT)
{
// One-shot mode
Expand All @@ -1707,18 +1744,21 @@ void MB_UpdateCycles(ULONG uExecutedCycles)
pMB->sy6522.TIMER1_COUNTER.w = pMB->sy6522.TIMER1_LATCH.w;
StartTimer1(pMB);
}

MB_Update();
}
else if ( bTimer1Underflow
&& !g_bMBTimerIrqActive // StopTimer1() has been called
&& (pMB->sy6522.IFR & IxR_TIMER1) // IRQ
&& ((pMB->sy6522.ACR & RUNMODE) == RM_ONESHOT) ) // One-shot mode
else if (pMB->bTimer2Active && bTimer2Underflow)
{
// Fix for Willy Byte - need to confirm that 6522 really does this!
// . It never accesses IER/IFR/TIMER1 regs to clear IRQ
pMB->sy6522.IFR &= ~IxR_TIMER1; // Deassert the TIMER IRQ
pMB->sy6522.IFR |= IxR_TIMER2;
UpdateIFR(pMB);

if((pMB->sy6522.ACR & RUNMODE) == RM_ONESHOT)
{
StopTimer2(pMB);
}
else
{
pMB->sy6522.TIMER2_COUNTER.w = pMB->sy6522.TIMER2_LATCH.w;
StartTimer2(pMB);
}
}
}
}
Expand All @@ -1732,7 +1772,6 @@ SS_CARDTYPE MB_GetSoundcardType()

void MB_SetSoundcardType(SS_CARDTYPE NewSoundcardType)
{
// if ((NewSoundcardType == SC_UNINIT) || (g_SoundcardType == NewSoundcardType))
if (g_SoundcardType == NewSoundcardType)
return;

Expand All @@ -1746,18 +1785,33 @@ void MB_SetSoundcardType(SS_CARDTYPE NewSoundcardType)

//-----------------------------------------------------------------------------

double MB_GetFramePeriod()
static double MB_GetFramePeriod(void)
{
return (g_bMBTimerIrqActive||(g_MB[0].sy6522.IFR & IxR_TIMER1)) ? (double)g_n6522TimerPeriod : g_f6522TimerPeriod_NoIRQ;
// TODO: Ideally remove this (slot-4) Phasor-IFR check: [*1]
// . It's for Phasor music player, which runs in one-shot mode:
// . MB_UpdateCycles()
// -> Timer1 underflows & StopTimer1() is called, which sets g_nMBTimerDevice == kTIMERDEVICE_INVALID
// . MB_EndOfVideoFrame(), and g_nMBTimerDevice == kTIMERDEVICE_INVALID
// -> MB_Update()
// -> MB_GetFramePeriod()
// NB. Removing this Phasor-IFR check means the occasional 'g_f6522TimerPeriod_NoIRQ' gets returned.

if ((g_nMBTimerDevice != kTIMERDEVICE_INVALID) ||
(g_bPhasorEnable && (g_MB[0].sy6522.IFR & IxR_TIMER1))) // [*1]
{
return (double)g_n6522TimerPeriod;
}
else
{
return g_f6522TimerPeriod_NoIRQ;
}
}

bool MB_IsActive()
{
if(!MockingboardVoice.bActive)
if (!MockingboardVoice.bActive)
return false;

// Ignore /g_bMBTimerIrqActive/ as timer's irq handler will access 6522 regs affecting /g_bMB_Active/

return g_bMB_Active;
}

Expand Down
1 change: 0 additions & 1 deletion source/Mockingboard.h
View file
Expand Up @@ -13,7 +13,6 @@ void MB_CheckIRQ();
void MB_UpdateCycles(ULONG uExecutedCycles);
SS_CARDTYPE MB_GetSoundcardType();
void MB_SetSoundcardType(SS_CARDTYPE NewSoundcardType);
double MB_GetFramePeriod();
bool MB_IsActive();
DWORD MB_GetVolume();
void MB_SetVolume(DWORD dwVolume, DWORD dwVolumeMax);
Expand Down

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