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vdp timing hacks

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This commit is contained in:
notaz 2017-10-04 02:58:48 +03:00
parent 3162a7104c
commit 334f00e24e
2 changed files with 28 additions and 18 deletions
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34
pico/pico_cmn.c
View file

@ -68,10 +68,28 @@ static void do_hint(struct PicoVideo *pv)
}
}
static void do_timing_hacks_as(struct PicoVideo *pv, int vdp_slots)
{
pv->lwrite_cnt += vdp_slots - Pico.m.dma_xfers * 2; // wrong *2
if (pv->lwrite_cnt > vdp_slots)
pv->lwrite_cnt = vdp_slots;
else if (pv->lwrite_cnt < 0)
pv->lwrite_cnt = 0;
if (Pico.m.dma_xfers)
SekCyclesBurn(CheckDMA());
}
static void do_timing_hacks_vb(void)
{
if (Pico.m.dma_xfers)
SekCyclesBurn(CheckDMA());
}
static int PicoFrameHints(void)
{
struct PicoVideo *pv = &Pico.video;
int line_sample = Pico.m.pal ? 68 : 93;
int vdp_slots = (Pico.video.reg[12] & 1) ? 18 : 16;
int lines, y, lines_vis, skip;
int vcnt_wrap, vcnt_adj;
unsigned int cycles;
@ -112,13 +130,6 @@ static int PicoFrameHints(void)
if ((y == 224 && !(pv->reg[1] & 8)) || y == 240)
break;
// VDP FIFO
pv->lwrite_cnt -= 12;
if (pv->lwrite_cnt <= 0) {
pv->lwrite_cnt = 0;
Pico.video.status |= SR_EMPT;
}
PAD_DELAY();
// H-Interrupts:
@ -160,7 +171,7 @@ static int PicoFrameHints(void)
// Run scanline:
line_base_cycles = SekCyclesDone();
if (Pico.m.dma_xfers) SekCyclesBurn(CheckDMA());
do_timing_hacks_as(pv, vdp_slots);
CPUS_RUN(CYCLES_M68K_LINE);
if (PicoLineHook) PicoLineHook();
@ -202,7 +213,7 @@ static int PicoFrameHints(void)
// also delay between F bit (bit 7) is set in SR and IRQ happens (Ex-Mutants)
// also delay between last H-int and V-int (Golden Axe 3)
line_base_cycles = SekCyclesDone();
if (Pico.m.dma_xfers) SekCyclesBurn(CheckDMA());
do_timing_hacks_vb();
CPUS_RUN(CYCLES_M68K_VINT_LAG);
if (pv->reg[1] & 0x20) {
@ -266,7 +277,7 @@ static int PicoFrameHints(void)
// Run scanline:
line_base_cycles = SekCyclesDone();
if (Pico.m.dma_xfers) SekCyclesBurn(CheckDMA());
do_timing_hacks_vb();
CPUS_RUN(CYCLES_M68K_LINE);
if (PicoLineHook) PicoLineHook();
@ -278,6 +289,7 @@ static int PicoFrameHints(void)
// last scanline
Pico.m.scanline = y;
pv->v_counter = 0xff;
pv->lwrite_cnt = 0;
PAD_DELAY();
@ -289,7 +301,7 @@ static int PicoFrameHints(void)
// Run scanline:
line_base_cycles = SekCyclesDone();
if (Pico.m.dma_xfers) SekCyclesBurn(CheckDMA());
do_timing_hacks_as(pv, vdp_slots);
CPUS_RUN(CYCLES_M68K_LINE);
if (PicoLineHook) PicoLineHook();

12
pico/videoport.c
View file

@ -377,14 +377,12 @@ PICO_INTERNAL_ASM void PicoVideoWrite(unsigned int a,unsigned short d)
}
// preliminary FIFO emulation for Chaos Engine, The (E)
if (!(pvid->status&8) && (pvid->reg[1]&0x40) && !(PicoOpt&POPT_DIS_VDP_FIFO)) // active display?
if (!(pvid->status & SR_VB) && (pvid->reg[1] & 0x40) && !(PicoOpt&POPT_DIS_VDP_FIFO)) // active display?
{
pvid->status&=~0x200; // FIFO no longer empty
pvid->lwrite_cnt++;
if (pvid->lwrite_cnt >= 4) pvid->status|=0x100; // FIFO full
if (pvid->lwrite_cnt > 4) {
SekCyclesBurnRun(32); // penalty // 488/12-8
}
int use = pvid->type == 1 ? 2 : 1;
pvid->lwrite_cnt -= use;
if (pvid->lwrite_cnt < 0)
SekCyclesLeft = 0;
elprintf(EL_ASVDP, "VDP data write: %04x [%06x] {%i} #%i @ %06x", d, Pico.video.addr,
Pico.video.type, pvid->lwrite_cnt, SekPc);
}