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32x: add preliminary hint emulation

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This commit is contained in:
notaz 2013-08-14 03:36:36 +03:00
parent b011c2af39
commit 5ac99d9adf
3 changed files with 36 additions and 3 deletions
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31
pico/32x/32x.c
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@ -228,6 +228,25 @@ static void p32x_start_blank(void)
p32x_sh2_poll_event(&ssh2, SH2_STATE_VPOLL, 0);
}
void p32x_schedule_hint(SH2 *sh2, int m68k_cycles)
{
// rather rough, 32x hint is useless in practice
int after;
if (!((Pico32x.sh2irq_mask[0] | Pico32x.sh2irq_mask[1]) & 4))
return; // nobody cares
// note: when Pico.m.scanline is 224, SH2s might
// still be at scanline 93 (or so)
if (!(Pico32x.sh2_regs[0] & 0x80) && Pico.m.scanline > 224)
return;
after = (Pico32x.sh2_regs[4 / 2] + 1) * 488;
if (sh2 != NULL)
p32x_event_schedule_sh2(sh2, P32X_EVENT_HINT, after);
else
p32x_event_schedule(m68k_cycles, P32X_EVENT_HINT, after);
}
// compare cycles, handling overflows
// check if a > b
#define CYCLES_GT(a, b) \
@ -244,6 +263,13 @@ static void fillend_event(unsigned int now)
p32x_sh2_poll_event(&ssh2, SH2_STATE_VPOLL, now);
}
static void hint_event(unsigned int now)
{
Pico32x.sh2irqs |= P32XI_HINT;
p32x_update_irls(NULL, now);
p32x_schedule_hint(NULL, now);
}
typedef void (event_cb)(unsigned int now);
unsigned int event_times[P32X_EVENT_COUNT];
@ -251,6 +277,7 @@ static unsigned int event_time_next;
static event_cb *event_cbs[] = {
[P32X_EVENT_PWM] = p32x_pwm_irq_event,
[P32X_EVENT_FILLEND] = fillend_event,
[P32X_EVENT_HINT] = hint_event,
};
// schedule event at some time 'after', in m68k clocks
@ -481,10 +508,14 @@ void sync_sh2s_lockstep(unsigned int m68k_target)
void PicoFrame32x(void)
{
Pico.m.scanline = 0;
Pico32x.vdp_regs[0x0a/2] &= ~P32XV_VBLK; // get out of vblank
if ((Pico32x.vdp_regs[0] & P32XV_Mx) != 0) // no forced blanking
Pico32x.vdp_regs[0x0a/2] &= ~P32XV_PEN; // no palette access
if (!(Pico32x.sh2_regs[0] & 0x80))
p32x_schedule_hint(NULL, SekCyclesDoneT2());
p32x_sh2_poll_event(&msh2, SH2_STATE_VPOLL, 0);
p32x_sh2_poll_event(&ssh2, SH2_STATE_VPOLL, 0);