The-Homebrew-Cloud/Genesis-Plus-GX
2
0
Fork 0
mirror of https://github.com/ekeeke/Genesis-Plus-GX.git synced 2024-11-13 06:15:07 +01:00
Code Issues Packages Projects Releases Wiki Activity

[Core/CPU] improved 68K/Z80 synchronization

Browse Source
This commit is contained in:
EkeEke 2018-01-07 16:24:28 +01:00
parent 238e520a4a
commit d0aa36acc3
4 changed files with 8 additions and 48 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
core/genesis.c
View File

@ -5,7 +5,7 @@
* Support for SG-1000, Mark-III, Master System, Game Gear, Mega Drive & Mega CD hardware
*
* Copyright (C) 1998-2003 Charles Mac Donald (original code)
* Copyright (C) 2007-2016 Eke-Eke (Genesis Plus GX)
* Copyright (C) 2007-2018 Eke-Eke (Genesis Plus GX)
*
* Redistribution and use of this code or any derivative works are permitted
* provided that the following conditions are met:
@ -474,8 +474,8 @@ void gen_zbusreq_w(unsigned int data, unsigned int cycles)
/* check if Z80 is going to be restarted */
if (zstate == 3)
{
/* resynchronize with 68k */
Z80.cycles = cycles;
/* resynchronize with 68k (Z80 cycles should remain a multiple of 15 MClocks) */
Z80.cycles = ((cycles + 14) / 15) * 15;
/* disable 68k access to Z80 bus */
m68k.memory_map[0xa0].read8 = m68k_read_bus_8;
@ -496,8 +496,8 @@ void gen_zreset_w(unsigned int data, unsigned int cycles)
/* check if Z80 is going to be restarted */
if (zstate == 0)
{
/* resynchronize with 68k */
Z80.cycles = cycles;
/* resynchronize with 68k (Z80 cycles should remain a multiple of 15 MClocks) */
Z80.cycles = ((cycles + 14) / 15) * 15;
/* reset Z80 & YM2612 */
z80_reset();

2
core/genesis.h
View File

@ -5,7 +5,7 @@
* Support for SG-1000, Mark-III, Master System, Game Gear, Mega Drive & Mega CD hardware
*
* Copyright (C) 1998-2003 Charles Mac Donald (original code)
* Copyright (C) 2007-2016 Eke-Eke (Genesis Plus GX)
* Copyright (C) 2007-2018 Eke-Eke (Genesis Plus GX)
*
* Redistribution and use of this code or any derivative works are permitted
* provided that the following conditions are met:

42
core/system.c
View File

@ -5,7 +5,7 @@
* Support for 16-bit & 8-bit hardware modes
*
* Copyright (C) 1998-2003 Charles Mac Donald (original code)
* Copyright (C) 2007-2017 Eke-Eke (Genesis Plus GX)
* Copyright (C) 2007-2018 Eke-Eke (Genesis Plus GX)
*
* Redistribution and use of this code or any derivative works are permitted
* provided that the following conditions are met:
@ -467,10 +467,6 @@ void system_frame_gen(int do_skip)
{
z80_run(788);
}
else
{
Z80.cycles = 788;
}
/* set VINT flag */
status |= 0x80;
@ -493,10 +489,6 @@ void system_frame_gen(int do_skip)
{
z80_run(MCYCLES_PER_LINE);
}
else
{
Z80.cycles = MCYCLES_PER_LINE;
}
/* Z80 interrupt is cleared at the end of the line */
Z80.irq_state = CLEAR_LINE;
@ -538,10 +530,6 @@ void system_frame_gen(int do_skip)
{
z80_run(mcycles_vdp + MCYCLES_PER_LINE);
}
else
{
Z80.cycles = mcycles_vdp + MCYCLES_PER_LINE;
}
/* run SVP chip */
if (svp)
@ -590,10 +578,6 @@ void system_frame_gen(int do_skip)
{
z80_run(mcycles_vdp + MCYCLES_PER_LINE);
}
else
{
Z80.cycles = mcycles_vdp + MCYCLES_PER_LINE;
}
/* run SVP chip */
if (svp)
@ -654,10 +638,6 @@ void system_frame_gen(int do_skip)
{
z80_run(mcycles_vdp + MCYCLES_PER_LINE);
}
else
{
Z80.cycles = mcycles_vdp + MCYCLES_PER_LINE;
}
/* run SVP chip */
if (svp)
@ -826,10 +806,6 @@ void system_frame_scd(int do_skip)
{
z80_run(788);
}
else
{
Z80.cycles = 788;
}
/* set VINT flag */
status |= 0x80;
@ -854,10 +830,6 @@ void system_frame_scd(int do_skip)
{
z80_run(MCYCLES_PER_LINE);
}
else
{
Z80.cycles = MCYCLES_PER_LINE;
}
/* Z80 interrupt is cleared at the end of the line */
Z80.irq_state = CLEAR_LINE;
@ -895,10 +867,6 @@ void system_frame_scd(int do_skip)
{
z80_run(mcycles_vdp + MCYCLES_PER_LINE);
}
else
{
Z80.cycles = mcycles_vdp + MCYCLES_PER_LINE;
}
/* update VDP cycle count */
mcycles_vdp += MCYCLES_PER_LINE;
@ -943,10 +911,6 @@ void system_frame_scd(int do_skip)
{
z80_run(mcycles_vdp + MCYCLES_PER_LINE);
}
else
{
Z80.cycles = mcycles_vdp + MCYCLES_PER_LINE;
}
/* update VDP cycle count */
mcycles_vdp += MCYCLES_PER_LINE;
@ -1003,10 +967,6 @@ void system_frame_scd(int do_skip)
{
z80_run(mcycles_vdp + MCYCLES_PER_LINE);
}
else
{
Z80.cycles = mcycles_vdp + MCYCLES_PER_LINE;
}
/* update VDP cycle count */
mcycles_vdp += MCYCLES_PER_LINE;

2
core/system.h
View File

@ -5,7 +5,7 @@
* Support for 16-bit & 8-bit hardware modes
*
* Copyright (C) 1998-2003 Charles Mac Donald (original code)
* Copyright (C) 2007-2017 Eke-Eke (Genesis Plus GX)
* Copyright (C) 2007-2018 Eke-Eke (Genesis Plus GX)
*
* Redistribution and use of this code or any derivative works are permitted
* provided that the following conditions are met: