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https://github.com/RaySollium99/picodrive.git
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vdp timing hacks
This commit is contained in:
parent
3162a7104c
commit
334f00e24e
2 changed files with 28 additions and 18 deletions
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@ -68,10 +68,28 @@ static void do_hint(struct PicoVideo *pv)
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}
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}
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static void do_timing_hacks_as(struct PicoVideo *pv, int vdp_slots)
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{
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pv->lwrite_cnt += vdp_slots - Pico.m.dma_xfers * 2; // wrong *2
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if (pv->lwrite_cnt > vdp_slots)
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pv->lwrite_cnt = vdp_slots;
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else if (pv->lwrite_cnt < 0)
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pv->lwrite_cnt = 0;
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if (Pico.m.dma_xfers)
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SekCyclesBurn(CheckDMA());
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}
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static void do_timing_hacks_vb(void)
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{
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if (Pico.m.dma_xfers)
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SekCyclesBurn(CheckDMA());
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}
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static int PicoFrameHints(void)
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{
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struct PicoVideo *pv = &Pico.video;
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int line_sample = Pico.m.pal ? 68 : 93;
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int vdp_slots = (Pico.video.reg[12] & 1) ? 18 : 16;
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int lines, y, lines_vis, skip;
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int vcnt_wrap, vcnt_adj;
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unsigned int cycles;
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@ -112,13 +130,6 @@ static int PicoFrameHints(void)
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if ((y == 224 && !(pv->reg[1] & 8)) || y == 240)
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break;
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// VDP FIFO
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pv->lwrite_cnt -= 12;
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if (pv->lwrite_cnt <= 0) {
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pv->lwrite_cnt = 0;
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Pico.video.status |= SR_EMPT;
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}
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PAD_DELAY();
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// H-Interrupts:
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@ -160,7 +171,7 @@ static int PicoFrameHints(void)
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// Run scanline:
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line_base_cycles = SekCyclesDone();
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if (Pico.m.dma_xfers) SekCyclesBurn(CheckDMA());
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do_timing_hacks_as(pv, vdp_slots);
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CPUS_RUN(CYCLES_M68K_LINE);
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if (PicoLineHook) PicoLineHook();
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@ -202,7 +213,7 @@ static int PicoFrameHints(void)
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// also delay between F bit (bit 7) is set in SR and IRQ happens (Ex-Mutants)
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// also delay between last H-int and V-int (Golden Axe 3)
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line_base_cycles = SekCyclesDone();
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if (Pico.m.dma_xfers) SekCyclesBurn(CheckDMA());
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do_timing_hacks_vb();
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CPUS_RUN(CYCLES_M68K_VINT_LAG);
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if (pv->reg[1] & 0x20) {
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@ -266,7 +277,7 @@ static int PicoFrameHints(void)
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// Run scanline:
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line_base_cycles = SekCyclesDone();
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if (Pico.m.dma_xfers) SekCyclesBurn(CheckDMA());
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do_timing_hacks_vb();
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CPUS_RUN(CYCLES_M68K_LINE);
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if (PicoLineHook) PicoLineHook();
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@ -278,6 +289,7 @@ static int PicoFrameHints(void)
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// last scanline
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Pico.m.scanline = y;
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pv->v_counter = 0xff;
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pv->lwrite_cnt = 0;
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PAD_DELAY();
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@ -289,7 +301,7 @@ static int PicoFrameHints(void)
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// Run scanline:
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line_base_cycles = SekCyclesDone();
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if (Pico.m.dma_xfers) SekCyclesBurn(CheckDMA());
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do_timing_hacks_as(pv, vdp_slots);
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CPUS_RUN(CYCLES_M68K_LINE);
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if (PicoLineHook) PicoLineHook();
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