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cd: fix cycle overflow issue

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This commit is contained in:
notaz 2013-10-04 23:24:36 +03:00
parent 5ad7000693
commit a6523294e2
4 changed files with 31 additions and 10 deletions
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32
pico/cd/mcd.c
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@ -11,7 +11,9 @@
extern unsigned char formatted_bram[4*0x10];
static unsigned int m68k_cycle_mult;
static unsigned int mcd_m68k_cycle_mult;
static unsigned int mcd_m68k_cycle_base;
static unsigned int mcd_s68k_cycle_base;
void (*PicoMCDopenTray)(void) = NULL;
void (*PicoMCDcloseTray)(void) = NULL;
@ -116,14 +118,14 @@ static void pcd_set_cycle_mult(void)
{
// ~1.63 for NTSC, ~1.645 for PAL
if (Pico.m.pal)
m68k_cycle_mult = ((12500000ull << 16) / (50*312*488));
mcd_m68k_cycle_mult = ((12500000ull << 16) / (50*312*488));
else
m68k_cycle_mult = ((12500000ull << 16) / (60*262*488)) + 1;
mcd_m68k_cycle_mult = ((12500000ull << 16) / (60*262*488)) + 1;
}
unsigned int pcd_cycles_m68k_to_s68k(unsigned int c)
{
return (long long)c * m68k_cycle_mult >> 16;
return (long long)c * mcd_m68k_cycle_mult >> 16;
}
/* events */
@ -234,10 +236,13 @@ static void pcd_run_events(unsigned int until)
int pcd_sync_s68k(unsigned int m68k_target, int m68k_poll_sync)
{
#define now SekCycleCntS68k
unsigned int s68k_target =
(unsigned long long)m68k_target * m68k_cycle_mult >> 16;
unsigned int s68k_target;
unsigned int target;
target = m68k_target - mcd_m68k_cycle_base;
s68k_target = mcd_s68k_cycle_base +
((unsigned long long)target * mcd_m68k_cycle_mult >> 16);
elprintf(EL_CD, "s68k sync to %u, %u->%u",
m68k_target, now, s68k_target);
@ -307,12 +312,21 @@ void pcd_run_cpus_lockstep(int m68k_cycles)
#include "../pico_cmn.c"
void pcd_prepare_frame(void)
{
pcd_set_cycle_mult();
// need this because we can't have direct mapping between
// master<->slave cycle counters because of overflows
mcd_m68k_cycle_base = SekCycleAim;
mcd_s68k_cycle_base = SekCycleAimS68k;
}
PICO_INTERNAL void PicoFrameMCD(void)
{
if (!(PicoOpt&POPT_ALT_RENDERER))
PicoFrameStart();
PicoFrameStart();
pcd_set_cycle_mult();
pcd_prepare_frame();
PicoFrameHints();
}