Fixed a bug in scx_delay’s calculation

This commit is contained in:
Lior Halphon 2017-09-11 23:56:35 +03:00
parent 14f267b4fa
commit 09b7e2fff4

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@ -292,12 +292,12 @@ static void update_display_state(GB_gameboy_t *gb, uint8_t cycles)
Todo: Investigate what causes the difference between our findings */ Todo: Investigate what causes the difference between our findings */
uint8_t stat_delay = gb->cgb_double_speed? 2 : 4; // (gb->cgb_mode? 0 : 4); uint8_t stat_delay = gb->cgb_double_speed? 2 : 4; // (gb->cgb_mode? 0 : 4);
/* Todo: Is this correct for DMG mode CGB? */ /* Todo: Is this correct for DMG mode CGB? */
uint8_t scx_delay = gb->effective_scx; uint8_t scx_delay = gb->effective_scx & 7;
if (gb->cgb_double_speed) { if (gb->cgb_double_speed) {
scx_delay = (scx_delay + 1) & ~1 & 7; scx_delay = (scx_delay + 1) & ~1;
} }
else { else {
scx_delay = (scx_delay + (gb->first_scanline ? 2 : 0)) & ~3 & 7; scx_delay = (scx_delay + (gb->first_scanline ? 2 : 0)) & ~3;
} }
/* Todo: These are correct for DMG, DMG-mode CGB, and single speed CGB. Is is correct for double speed CGB? */ /* Todo: These are correct for DMG, DMG-mode CGB, and single speed CGB. Is is correct for double speed CGB? */