unsigned long Memory::event(unsigned long cycleCounter) {
if (lastOamDmaUpdate != DISABLED_TIME)
updateOamDma(cycleCounter);
switch (intreq.minEventId()) {
case UNHALT:
nontrivial_ff_write(0xFF04, 0, cycleCounter);
PC = (PC + 1) & 0xFFFF;
cycleCounter += 4;
intreq.unhalt();
intreq.setEventTime<UNHALT>(DISABLED_TIME);
break;
case END:
intreq.setEventTime<END>(DISABLED_TIME - 1);
while (cycleCounter >= intreq.minEventTime() && intreq.eventTime(END) != DISABLED_TIME)
cycleCounter = event(cycleCounter);
intreq.setEventTime<END>(DISABLED_TIME);
break;
case BLIT:
{
const bool lcden = ioamhram[0x140] >> 7 & 1;
unsigned long blitTime = intreq.eventTime(BLIT);
if (lcden | blanklcd) {
display.updateScreen(blanklcd, cycleCounter);
intreq.setEventTime<BLIT>(DISABLED_TIME);
intreq.setEventTime<END>(DISABLED_TIME);
while (cycleCounter >= intreq.minEventTime())
cycleCounter = event(cycleCounter);
} else
blitTime += 70224 << isDoubleSpeed();
blanklcd = lcden ^ 1;
intreq.setEventTime<BLIT>(blitTime);
}
break;
case SERIAL:
updateSerial(cycleCounter);
break;
case OAM:
intreq.setEventTime<OAM>(lastOamDmaUpdate == DISABLED_TIME ?
static_cast<unsigned long>(DISABLED_TIME) : intreq.eventTime(OAM) + 0xA0 * 4);
break;
case DMA:
{
const bool doubleSpeed = isDoubleSpeed();
unsigned dmaSrc = dmaSource;
unsigned dmaDest = dmaDestination;
unsigned dmaLength = ((ioamhram[0x155] & 0x7F) + 0x1) * 0x10;
unsigned length = hdmaReqFlagged(intreq) ? 0x10 : dmaLength;
ackDmaReq(&intreq);
if ((static_cast<unsigned long>(dmaDest) + length) & 0x10000) {
length = 0x10000 - dmaDest;
ioamhram[0x155] |= 0x80;
}
dmaLength -= length;
if (!(ioamhram[0x140] & 0x80))
dmaLength = 0;
{
unsigned long lOamDmaUpdate = lastOamDmaUpdate;
lastOamDmaUpdate = DISABLED_TIME;
while (length--) {
const unsigned src = dmaSrc++ & 0xFFFF;
const unsigned data = ((src & 0xE000) == 0x8000 || src > 0xFDFF) ? 0xFF : read(src, cycleCounter);
cycleCounter += 2 << doubleSpeed;
if (cycleCounter - 3 > lOamDmaUpdate) {
oamDmaPos = (oamDmaPos + 1) & 0xFF;
lOamDmaUpdate += 4;
if (oamDmaPos < 0xA0) {
if (oamDmaPos == 0)
startOamDma(lOamDmaUpdate - 1);
ioamhram[src & 0xFF] = data;
} else if (oamDmaPos == 0xA0) {
endOamDma(lOamDmaUpdate - 1);
lOamDmaUpdate = DISABLED_TIME;
}
}
nontrivial_write(0x8000 | (dmaDest++ & 0x1FFF), data, cycleCounter);
}
lastOamDmaUpdate = lOamDmaUpdate;
}
cycleCounter += 4;
dmaSource = dmaSrc;
dmaDestination = dmaDest;
ioamhram[0x155] = ((dmaLength / 0x10 - 0x1) & 0xFF) | (ioamhram[0x155] & 0x80);
if ((ioamhram[0x155] & 0x80) && display.hdmaIsEnabled()) {
if (lastOamDmaUpdate != DISABLED_TIME)
updateOamDma(cycleCounter);
display.disableHdma(cycleCounter);
}
}
break;
case TIMA:
tima.doIrqEvent(TimaInterruptRequester(intreq));
break;
case VIDEO:
display.update(cycleCounter);
break;
case INTERRUPTS:
if (stopped) {
intreq.setEventTime<INTERRUPTS>(DISABLED_TIME);
break;
}
if (halted()) {
if (gbIsCgb_ || (!gbIsCgb_ && cycleCounter <= halttime + 4))
cycleCounter += 4;
intreq.unhalt();
intreq.setEventTime<UNHALT>(DISABLED_TIME);
}
if (ime()) {
unsigned address;
cycleCounter += 12;
display.update(cycleCounter);
SP = (SP - 2) & 0xFFFF;
write(SP + 1, PC >> 8, cycleCounter);
unsigned ie = intreq.iereg();
cycleCounter += 4;
display.update(cycleCounter);
write(SP, PC & 0xFF, cycleCounter);
const unsigned pendingIrqs = ie & intreq.ifreg();
cycleCounter += 4;
display.update(cycleCounter);
const unsigned n = pendingIrqs & -pendingIrqs;
if (n == 0) {
address = 0;
}
else if (n < 8) {
static const unsigned char lut[] = { 0x40, 0x48, 0x48, 0x50 };
address = lut[n-1];
} else
address = 0x50 + n;
intreq.ackIrq(n);
PC = address;
}
break;
}
return cycleCounter;
}
unsigned long Memory::event(unsigned long cc) {
if (lastOamDmaUpdate_ != disabled_time)
updateOamDma(cc);
switch (intreq_.minEventId()) {
case intevent_unhalt:
intreq_.unhalt();
intreq_.setEventTime<intevent_unhalt>(disabled_time);
break;
case intevent_end:
intreq_.setEventTime<intevent_end>(disabled_time - 1);
while (cc >= intreq_.minEventTime()
&& intreq_.eventTime(intevent_end) != disabled_time) {
cc = event(cc);
}
intreq_.setEventTime<intevent_end>(disabled_time);
break;
case intevent_blit:
{
bool const lcden = ioamhram_[0x140] & lcdc_en;
unsigned long blitTime = intreq_.eventTime(intevent_blit);
if (lcden | blanklcd_) {
lcd_.updateScreen(blanklcd_, cc);
intreq_.setEventTime<intevent_blit>(disabled_time);
intreq_.setEventTime<intevent_end>(disabled_time);
while (cc >= intreq_.minEventTime())
cc = event(cc);
} else
blitTime += 70224 << isDoubleSpeed();
blanklcd_ = lcden ^ 1;
intreq_.setEventTime<intevent_blit>(blitTime);
}
break;
case intevent_serial:
updateSerial(cc);
break;
case intevent_oam:
intreq_.setEventTime<intevent_oam>(lastOamDmaUpdate_ == disabled_time
? static_cast<unsigned long>(disabled_time)
: intreq_.eventTime(intevent_oam) + 0xA0 * 4);
break;
case intevent_dma:
{
bool const doubleSpeed = isDoubleSpeed();
unsigned dmaSrc = dmaSource_;
unsigned dmaDest = dmaDestination_;
unsigned dmaLength = ((ioamhram_[0x155] & 0x7F) + 0x1) * 0x10;
unsigned length = hdmaReqFlagged(intreq_) ? 0x10 : dmaLength;
ackDmaReq(intreq_);
if ((static_cast<unsigned long>(dmaDest) + length) & 0x10000) {
length = 0x10000 - dmaDest;
ioamhram_[0x155] |= 0x80;
}
dmaLength -= length;
if (!(ioamhram_[0x140] & lcdc_en))
dmaLength = 0;
{
unsigned long lOamDmaUpdate = lastOamDmaUpdate_;
lastOamDmaUpdate_ = disabled_time;
while (length--) {
unsigned const src = dmaSrc++ & 0xFFFF;
unsigned const data = (src & 0xE000) == 0x8000 || src > 0xFDFF
? 0xFF
: read(src, cc);
cc += 2 << doubleSpeed;
if (cc - 3 > lOamDmaUpdate) {
oamDmaPos_ = (oamDmaPos_ + 1) & 0xFF;
lOamDmaUpdate += 4;
if (oamDmaPos_ < 0xA0) {
if (oamDmaPos_ == 0)
startOamDma(lOamDmaUpdate - 1);
ioamhram_[src & 0xFF] = data;
} else if (oamDmaPos_ == 0xA0) {
endOamDma(lOamDmaUpdate - 1);
lOamDmaUpdate = disabled_time;
}
}
nontrivial_write(0x8000 | (dmaDest++ & 0x1FFF), data, cc);
}
lastOamDmaUpdate_ = lOamDmaUpdate;
}
cc += 4;
dmaSource_ = dmaSrc;
dmaDestination_ = dmaDest;
ioamhram_[0x155] = ((dmaLength / 0x10 - 0x1) & 0xFF) | (ioamhram_[0x155] & 0x80);
if ((ioamhram_[0x155] & 0x80) && lcd_.hdmaIsEnabled()) {
if (lastOamDmaUpdate_ != disabled_time)
updateOamDma(cc);
lcd_.disableHdma(cc);
}
}
break;
case intevent_tima:
tima_.doIrqEvent(TimaInterruptRequester(intreq_));
break;
case intevent_video:
lcd_.update(cc);
break;
case intevent_interrupts:
if (halted()) {
if (isCgb())
cc += 4;
intreq_.unhalt();
intreq_.setEventTime<intevent_unhalt>(disabled_time);
}
if (ime()) {
unsigned const pendingIrqs = intreq_.pendingIrqs();
unsigned const n = pendingIrqs & -pendingIrqs;
unsigned address;
if (n <= 4) {
static unsigned char const lut[] = { 0x40, 0x48, 0x48, 0x50 };
address = lut[n-1];
} else
address = 0x50 + n;
intreq_.ackIrq(n);
cc = interrupter_.interrupt(address, cc, *this);
}
break;
}
return cc;
}