mirror of
https://github.com/RaySollium99/picodrive.git
synced 2025-09-05 07:17:45 -04:00
352 lines
8.6 KiB
C
352 lines
8.6 KiB
C
/*
|
|
* common code for base/cd/32x
|
|
* (C) notaz, 2007-2009,2013
|
|
*
|
|
* This work is licensed under the terms of MAME license.
|
|
* See COPYING file in the top-level directory.
|
|
*/
|
|
|
|
#define CYCLES_M68K_LINE 488 // suitable for both PAL/NTSC
|
|
#define CYCLES_M68K_VINT_LAG 112
|
|
|
|
// pad delay (for 6 button pads)
|
|
#define PAD_DELAY() { \
|
|
if(Pico.m.padDelay[0]++ > 25) Pico.m.padTHPhase[0]=0; \
|
|
if(Pico.m.padDelay[1]++ > 25) Pico.m.padTHPhase[1]=0; \
|
|
}
|
|
|
|
// CPUS_RUN
|
|
#ifndef CPUS_RUN
|
|
#define CPUS_RUN(m68k_cycles) \
|
|
SekRunM68k(m68k_cycles)
|
|
#endif
|
|
|
|
// sync m68k to Pico.t.m68c_aim
|
|
static void SekExecM68k(int cyc_do)
|
|
{
|
|
Pico.t.m68c_cnt += cyc_do;
|
|
|
|
#if defined(EMU_C68K)
|
|
PicoCpuCM68k.cycles = cyc_do;
|
|
CycloneRun(&PicoCpuCM68k);
|
|
Pico.t.m68c_cnt -= PicoCpuCM68k.cycles;
|
|
#elif defined(EMU_M68K)
|
|
Pico.t.m68c_cnt += m68k_execute(cyc_do) - cyc_do;
|
|
#elif defined(EMU_F68K)
|
|
Pico.t.m68c_cnt += fm68k_emulate(&PicoCpuFM68k, cyc_do, 0) - cyc_do;
|
|
#endif
|
|
SekCyclesLeft = 0;
|
|
}
|
|
|
|
static int SekSyncM68k(int once)
|
|
{
|
|
int cyc_do;
|
|
|
|
pprof_start(m68k);
|
|
pevt_log_m68k_o(EVT_RUN_START);
|
|
|
|
while ((cyc_do = Pico.t.m68c_aim - Pico.t.m68c_cnt) > 0) {
|
|
// the Z80 CPU is stealing some bus cycles from the 68K main CPU when
|
|
// accessing the main bus. Account for these by shortening the time
|
|
// the 68K CPU runs.
|
|
int z80_buscyc = Pico.t.z80_buscycles >> (~Pico.m.scanline & 1);
|
|
if (z80_buscyc <= cyc_do)
|
|
SekExecM68k(cyc_do - z80_buscyc);
|
|
else
|
|
z80_buscyc = cyc_do;
|
|
Pico.t.m68c_cnt += z80_buscyc;
|
|
Pico.t.z80_buscycles -= z80_buscyc;
|
|
if (once) break;
|
|
}
|
|
|
|
SekTrace(0);
|
|
pevt_log_m68k_o(EVT_RUN_END);
|
|
pprof_end(m68k);
|
|
|
|
return Pico.t.m68c_aim > Pico.t.m68c_cnt;
|
|
}
|
|
|
|
static __inline void SekAimM68k(int cyc, int mult)
|
|
{
|
|
// refresh slowdown, for cart: 2 cycles every 128 - make this 1 every 64,
|
|
// for RAM: seems to be 0-3 every 128. Carts usually run from the cart
|
|
// area, but MCD games only use RAM, hence a different multiplier is needed.
|
|
// NB must be quite accurate, so handle fractions as well (c/f OutRunners)
|
|
int delay = (Pico.t.refresh_delay += cyc*mult) >> 14;
|
|
Pico.t.m68c_cnt += delay;
|
|
Pico.t.refresh_delay -= delay << 14;
|
|
Pico.t.m68c_aim += cyc;
|
|
}
|
|
|
|
static __inline void SekRunM68k(int cyc)
|
|
{
|
|
// TODO 0x100 would be 2 cycles/128, moreover far too sensitive
|
|
SekAimM68k(cyc, 0x10c); // OutRunners, testpico, VDPFIFOTesting
|
|
SekSyncM68k(0);
|
|
}
|
|
|
|
static void SyncCPUs(unsigned int cycles)
|
|
{
|
|
// sync cpus
|
|
if (Pico.m.z80Run && !Pico.m.z80_reset && (PicoIn.opt&POPT_EN_Z80))
|
|
PicoSyncZ80(cycles);
|
|
|
|
#ifdef PICO_CD
|
|
if (PicoIn.AHW & PAHW_MCD)
|
|
pcd_sync_s68k(cycles, 0);
|
|
#endif
|
|
#ifdef PICO_32X
|
|
p32x_sync_sh2s(cycles);
|
|
#endif
|
|
}
|
|
|
|
static void do_hint(struct PicoVideo *pv)
|
|
{
|
|
pv->pending_ints |= 0x10;
|
|
if (pv->reg[0] & 0x10) {
|
|
elprintf(EL_INTS, "hint: @ %06x [%u]", SekPc, SekCyclesDone());
|
|
if (SekIrqLevel < pv->hint_irq)
|
|
SekInterrupt(pv->hint_irq);
|
|
}
|
|
}
|
|
|
|
static void do_timing_hacks_end(struct PicoVideo *pv)
|
|
{
|
|
PicoVideoFIFOSync(CYCLES_M68K_LINE);
|
|
|
|
// need rather tight Z80 sync for emulation of main bus cycle stealing
|
|
if (Pico.m.scanline&1)
|
|
if (Pico.m.z80Run && !Pico.m.z80_reset && (PicoIn.opt&POPT_EN_Z80))
|
|
PicoSyncZ80(Pico.t.m68c_aim);
|
|
}
|
|
|
|
static void do_timing_hacks_start(struct PicoVideo *pv)
|
|
{
|
|
int cycles = PicoVideoFIFOHint();
|
|
|
|
SekCyclesBurn(cycles); // prolong cpu HOLD if necessary
|
|
// XXX how to handle Z80 bus cycle stealing during DMA correctly?
|
|
if ((Pico.t.z80_buscycles -= cycles) < 0)
|
|
Pico.t.z80_buscycles = 0;
|
|
Pico.t.m68c_aim += Pico.m.scanline&1; // add 1 every 2 lines for 488.5 cycles
|
|
}
|
|
|
|
static int PicoFrameHints(void)
|
|
{
|
|
struct PicoVideo *pv = &Pico.video;
|
|
int lines, y, lines_vis, skip;
|
|
int hint; // Hint counter
|
|
|
|
pevt_log_m68k_o(EVT_FRAME_START);
|
|
|
|
skip = PicoIn.skipFrame;
|
|
|
|
z80_resetCycles(cycles_68k_to_z80(Pico.t.m68c_aim - Pico.t.m68c_frame_start));
|
|
Pico.t.m68c_frame_start = Pico.t.m68c_aim;
|
|
PsndStartFrame();
|
|
|
|
hint = pv->hint_cnt;
|
|
|
|
// === active display ===
|
|
pv->status |= PVS_ACTIVE;
|
|
|
|
for (y = 0; y < 240; y++)
|
|
{
|
|
if (y == 224 && !(pv->reg[1] & 8))
|
|
break;
|
|
|
|
Pico.m.scanline = y;
|
|
pv->v_counter = PicoVideoGetV(y, 0);
|
|
|
|
PAD_DELAY();
|
|
|
|
// H-Interrupts:
|
|
if (--hint < 0)
|
|
{
|
|
hint = pv->reg[10]; // Reload H-Int counter
|
|
do_hint(pv);
|
|
}
|
|
|
|
// decide if we draw this line
|
|
if (unlikely(PicoIn.opt & POPT_ALT_RENDERER) && !skip)
|
|
{
|
|
// find the right moment for frame renderer, when display is no longer blanked
|
|
if ((pv->reg[1]&0x40) || y > 100) {
|
|
if (Pico.est.rendstatus & PDRAW_SYNC_NEEDED)
|
|
PicoFrameFull();
|
|
#ifdef DRAW_FINISH_FUNC
|
|
DRAW_FINISH_FUNC();
|
|
#endif
|
|
Pico.est.rendstatus &= ~PDRAW_SYNC_NEEDED;
|
|
skip = 1;
|
|
}
|
|
}
|
|
|
|
// Run scanline:
|
|
Pico.t.m68c_line_start = Pico.t.m68c_aim;
|
|
do_timing_hacks_start(pv);
|
|
CPUS_RUN(CYCLES_M68K_LINE);
|
|
do_timing_hacks_end(pv);
|
|
|
|
if (PicoLineHook) PicoLineHook();
|
|
pevt_log_m68k_o(EVT_NEXT_LINE);
|
|
}
|
|
|
|
SyncCPUs(Pico.t.m68c_aim);
|
|
|
|
if (!skip)
|
|
{
|
|
if (Pico.est.DrawScanline < y)
|
|
PicoVideoSync(-1);
|
|
#ifdef DRAW_FINISH_FUNC
|
|
DRAW_FINISH_FUNC();
|
|
#endif
|
|
Pico.est.rendstatus &= ~PDRAW_SYNC_NEEDED;
|
|
}
|
|
#ifdef PICO_32X
|
|
p32x_render_frame();
|
|
#endif
|
|
|
|
// === VBLANK, 1st line ===
|
|
lines_vis = (pv->reg[1] & 8) ? 240 : 224;
|
|
if (y == lines_vis)
|
|
pv->status &= ~PVS_ACTIVE;
|
|
Pico.m.scanline = y;
|
|
pv->v_counter = PicoVideoGetV(y, 0);
|
|
|
|
memcpy(PicoIn.padInt, PicoIn.pad, sizeof(PicoIn.padInt));
|
|
PAD_DELAY();
|
|
|
|
// Last H-Int (normally):
|
|
if (--hint < 0)
|
|
{
|
|
hint = pv->reg[10]; // Reload H-Int counter
|
|
do_hint(pv);
|
|
}
|
|
|
|
pv->status |= SR_VB | PVS_VB2; // go into vblank
|
|
#ifdef PICO_32X
|
|
p32x_start_blank();
|
|
#endif
|
|
|
|
// the following SekRun is there for several reasons:
|
|
// there must be a delay after vblank bit is set and irq is asserted (Mazin Saga)
|
|
// 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)
|
|
Pico.t.m68c_line_start = Pico.t.m68c_aim;
|
|
PicoVideoFIFOMode(pv->reg[1]&0x40, pv->reg[12]&1);
|
|
do_timing_hacks_start(pv);
|
|
CPUS_RUN(CYCLES_M68K_VINT_LAG);
|
|
|
|
SyncCPUs(Pico.t.m68c_aim);
|
|
|
|
pv->status |= SR_F;
|
|
pv->pending_ints |= 0x20;
|
|
|
|
if (pv->reg[1] & 0x20) {
|
|
if (Pico.t.m68c_cnt - Pico.t.m68c_aim < 60) // CPU blocked?
|
|
SekExecM68k(11); // HACK
|
|
elprintf(EL_INTS, "vint: @ %06x [%u]", SekPc, SekCyclesDone());
|
|
SekInterrupt(6);
|
|
}
|
|
|
|
// assert Z80 interrupt for one scanline even in busrq hold (Teddy Blues)
|
|
if (/*Pico.m.z80Run &&*/ !Pico.m.z80_reset && (PicoIn.opt&POPT_EN_Z80)) {
|
|
elprintf(EL_INTS, "zint");
|
|
z80_int_assert(1);
|
|
}
|
|
|
|
// Run scanline:
|
|
CPUS_RUN(CYCLES_M68K_LINE - CYCLES_M68K_VINT_LAG);
|
|
do_timing_hacks_end(pv);
|
|
|
|
if (PicoLineHook) PicoLineHook();
|
|
pevt_log_m68k_o(EVT_NEXT_LINE);
|
|
|
|
if (Pico.m.z80Run && !Pico.m.z80_reset && (PicoIn.opt&POPT_EN_Z80))
|
|
PicoSyncZ80(Pico.t.m68c_aim);
|
|
z80_int_assert(0);
|
|
|
|
// === VBLANK ===
|
|
lines = Pico.m.pal ? 313 : 262;
|
|
for (y++; y < lines - 1; y++)
|
|
{
|
|
Pico.m.scanline = y;
|
|
pv->v_counter = PicoVideoGetV(y, 1);
|
|
|
|
PAD_DELAY();
|
|
|
|
if (unlikely(pv->status & PVS_ACTIVE) && --hint < 0)
|
|
{
|
|
hint = pv->reg[10]; // Reload H-Int counter
|
|
do_hint(pv);
|
|
}
|
|
|
|
// Run scanline:
|
|
Pico.t.m68c_line_start = Pico.t.m68c_aim;
|
|
do_timing_hacks_start(pv);
|
|
CPUS_RUN(CYCLES_M68K_LINE);
|
|
do_timing_hacks_end(pv);
|
|
|
|
if (PicoLineHook) PicoLineHook();
|
|
pevt_log_m68k_o(EVT_NEXT_LINE);
|
|
}
|
|
|
|
if (unlikely(PicoIn.overclockM68k)) {
|
|
unsigned int l = PicoIn.overclockM68k * lines / 100;
|
|
while (l-- > 0) {
|
|
Pico.t.m68c_cnt -= CYCLES_M68K_LINE;
|
|
do_timing_hacks_start(pv);
|
|
SekSyncM68k(0);
|
|
do_timing_hacks_end(pv);
|
|
}
|
|
}
|
|
|
|
// === VBLANK last line ===
|
|
pv->status &= ~(SR_VB | PVS_VB2);
|
|
pv->status |= ((pv->reg[1] >> 3) ^ SR_VB) & SR_VB; // forced blanking
|
|
|
|
// last scanline
|
|
Pico.m.scanline = y++;
|
|
pv->v_counter = 0xff;
|
|
|
|
PAD_DELAY();
|
|
|
|
if (unlikely(pv->status & PVS_ACTIVE)) {
|
|
if (--hint < 0) {
|
|
hint = pv->reg[10]; // Reload H-Int counter
|
|
do_hint(pv);
|
|
}
|
|
}
|
|
else
|
|
hint = pv->reg[10];
|
|
|
|
// Run scanline:
|
|
Pico.t.m68c_line_start = Pico.t.m68c_aim;
|
|
PicoVideoFIFOMode(pv->reg[1]&0x40, pv->reg[12]&1);
|
|
do_timing_hacks_start(pv);
|
|
CPUS_RUN(CYCLES_M68K_LINE);
|
|
do_timing_hacks_end(pv);
|
|
|
|
if (PicoLineHook) PicoLineHook();
|
|
pevt_log_m68k_o(EVT_NEXT_LINE);
|
|
|
|
SyncCPUs(Pico.t.m68c_aim);
|
|
#ifdef PICO_32X
|
|
p32x_end_blank();
|
|
#endif
|
|
|
|
// get samples from sound chips
|
|
PsndGetSamples(y);
|
|
|
|
timers_cycle(cycles_68k_to_z80(Pico.t.m68c_aim - Pico.t.m68c_frame_start));
|
|
|
|
pv->hint_cnt = hint;
|
|
|
|
return 0;
|
|
}
|
|
|
|
#undef PAD_DELAY
|
|
#undef CPUS_RUN
|
|
|
|
// vim:shiftwidth=2:ts=2:expandtab
|