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partial gmv implementation

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git-svn-id: file:///home/notaz/opt/svn/PicoDrive@6 be3aeb3a-fb24-0410-a615-afba39da0efa
This commit is contained in:
notaz 2006-12-25 15:17:54 +00:00
parent 4f67228034
commit 312e9ce192
8 changed files with 109 additions and 48 deletions
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44
Pico/Pico.c
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@ -194,22 +194,32 @@ static int dma_timings[] = {
9, 18, 17, 9 // ...
};
static void CheckDMA(void)
static int dma_bsycles[] = {
(488<<8)/83, (488<<8)/167, (488<<8)/166, (488<<8)/83,
(488<<8)/102, (488<<8)/205, (488<<8)/204, (488<<8)/102,
(488<<8)/8, (488<<8)/16, (488<<8)/15, (488<<8)/8,
(488<<8)/9, (488<<8)/18, (488<<8)/17, (488<<8)/9
};
//static
int CheckDMA(void)
{
int burn = 0, bytes_can = 0, dma_op = Pico.video.reg[0x17]>>6; // see gens for 00 and 01 modes
int bytes = Pico.m.dma_bytes;
int dma_op1;
if(dma_op & 2) bytes_can = dma_op;
else if(Pico.video.type!=1) bytes_can = 1; // setting dma_timings offset here according to Gens
if(Pico.video.reg[12] & 1) bytes_can += 4; // 40 cell mode?
if(!(Pico.video.status&8)&&(Pico.video.reg[1]&0x40)) { dma_op|=4; bytes_can += 8; } // active display?
bytes_can = dma_timings[bytes_can];
if(!(dma_op&2)) dma_op = (Pico.video.type==1) ? 0 : 1; // setting dma_timings offset here according to Gens
dma_op1 = dma_op;
if(Pico.video.reg[12] & 1) dma_op |= 4; // 40 cell mode?
if(!(Pico.video.status&8)&&(Pico.video.reg[1]&0x40)) dma_op|=8; // active display?
bytes_can = dma_timings[dma_op];
if(bytes <= bytes_can) {
if(dma_op&2) Pico.video.status&=~2; // dma no longer busy
else {
if(dma_op&4) burn = bytes*(((488<<8)/18 ))>>8; // have to be approximate because can't afford division..
else burn = bytes*(((488<<8)/205))>>8;
burn = bytes * dma_bsycles[dma_op] >> 8; // have to be approximate because can't afford division..
//SekCycleCnt-=Pico.m.dma_endcycles;
//Pico.m.dma_endcycles = 0;
}
Pico.m.dma_bytes = 0;
} else {
@ -217,8 +227,10 @@ static void CheckDMA(void)
Pico.m.dma_bytes -= bytes_can;
}
SekCycleCnt+=burn;
dprintf("~Dma %i op=%i can=%i burn=%i [%i|%i]", Pico.m.dma_bytes, dma_op, bytes_can, burn, Pico.m.scanline, SekCyclesDone());
//SekCycleCnt+=burn;
dprintf("~Dma %i op=%i can=%i burn=%i [%i|%i]", Pico.m.dma_bytes, dma_op1, bytes_can, burn, Pico.m.scanline, SekCyclesDone());
//dprintf("~aim: %i, cnt: %i", SekCycleAim, SekCycleCnt);
return burn;
}
static __inline void SekRun(int cyc)
@ -250,7 +262,9 @@ static __inline void SekRun(int cyc)
Pico.m.scanline, SekCyclesDone());
}
#endif
//dprintf("aim: %i, cnt: %i", SekCycleAim, SekCycleCnt);
if((cyc_do=SekCycleAim-SekCycleCnt) <= 0) return;
//dprintf("cyc_do: %i", cyc_do);
#if defined(EMU_C68K) && defined(EMU_M68K)
// this means we do run-compare Cyclone vs Musashi
SekCycleCnt+=CM_compareRun(cyc_do);
@ -390,12 +404,14 @@ static int PicoFrameHints(void)
// V-Interrupt:
if (y == lines_vis)
{
//dprintf("vint: @ %06x [%i|%i]", SekPc, y, SekCycleCnt);
pv->status|=0x88; // V-Int happened, go into vblank
dprintf("vint: @ %06x [%i|%i], aim=%i cnt=%i", SekPc, y, SekCycleCnt, SekCycleAim, SekCycleCnt);
pv->status|=0x08; // go into vblank
if(!Pico.m.dma_bytes||(Pico.video.reg[0x17]&0x80)) {
// there must be a gap between H and V ints, also after vblank bit set (Mazin Saga, Bram Stoker's Dracula)
SekRun(128); SekCycleAim-=128;
SekRun(128); SekCycleAim-=128; // 128; ?
}
dprintf("[%i|%i], aim=%i cnt=%i @ %x", y, SekCycleCnt, SekCycleAim, SekCycleCnt, SekPc);
pv->status|=0x80; // V-Int happened
pv->pending_ints|=0x20;
if(pv->reg[1]&0x20) SekInterrupt(6);
if(Pico.m.z80Run && (PicoOpt&4)) // ?
@ -421,7 +437,7 @@ static int PicoFrameHints(void)
getSamples(y);
// Run scanline:
if(Pico.m.dma_bytes) CheckDMA();
if(Pico.m.dma_bytes) SekCycleCnt+=CheckDMA();
SekRun(cycles_68k);
if((PicoOpt&4) && Pico.m.z80Run) {
Pico.m.z80Run|=2;