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[Core/CPU] improved 68K/Z80 synchronization

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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
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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 * 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) 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 * Redistribution and use of this code or any derivative works are permitted
* provided that the following conditions are met: * 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 */ /* check if Z80 is going to be restarted */
if (zstate == 3) if (zstate == 3)
{ {
/* resynchronize with 68k */ /* resynchronize with 68k (Z80 cycles should remain a multiple of 15 MClocks) */
Z80.cycles = cycles; Z80.cycles = ((cycles + 14) / 15) * 15;
/* disable 68k access to Z80 bus */ /* disable 68k access to Z80 bus */
m68k.memory_map[0xa0].read8 = m68k_read_bus_8; 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 */ /* check if Z80 is going to be restarted */
if (zstate == 0) if (zstate == 0)
{ {
/* resynchronize with 68k */ /* resynchronize with 68k (Z80 cycles should remain a multiple of 15 MClocks) */
Z80.cycles = cycles; Z80.cycles = ((cycles + 14) / 15) * 15;
/* reset Z80 & YM2612 */ /* reset Z80 & YM2612 */
z80_reset(); 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 * 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) 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 * Redistribution and use of this code or any derivative works are permitted
* provided that the following conditions are met: * 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 * Support for 16-bit & 8-bit hardware modes
* *
* Copyright (C) 1998-2003 Charles Mac Donald (original code) * 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 * Redistribution and use of this code or any derivative works are permitted
* provided that the following conditions are met: * provided that the following conditions are met:
@ -467,10 +467,6 @@ void system_frame_gen(int do_skip)
{ {
z80_run(788); z80_run(788);
} }
else
{
Z80.cycles = 788;
}
/* set VINT flag */ /* set VINT flag */
status |= 0x80; status |= 0x80;
@ -493,10 +489,6 @@ void system_frame_gen(int do_skip)
{ {
z80_run(MCYCLES_PER_LINE); z80_run(MCYCLES_PER_LINE);
} }
else
{
Z80.cycles = MCYCLES_PER_LINE;
}
/* Z80 interrupt is cleared at the end of the line */ /* Z80 interrupt is cleared at the end of the line */
Z80.irq_state = CLEAR_LINE; Z80.irq_state = CLEAR_LINE;
@ -538,10 +530,6 @@ void system_frame_gen(int do_skip)
{ {
z80_run(mcycles_vdp + MCYCLES_PER_LINE); z80_run(mcycles_vdp + MCYCLES_PER_LINE);
} }
else
{
Z80.cycles = mcycles_vdp + MCYCLES_PER_LINE;
}
/* run SVP chip */ /* run SVP chip */
if (svp) if (svp)
@ -590,10 +578,6 @@ void system_frame_gen(int do_skip)
{ {
z80_run(mcycles_vdp + MCYCLES_PER_LINE); z80_run(mcycles_vdp + MCYCLES_PER_LINE);
} }
else
{
Z80.cycles = mcycles_vdp + MCYCLES_PER_LINE;
}
/* run SVP chip */ /* run SVP chip */
if (svp) if (svp)
@ -654,10 +638,6 @@ void system_frame_gen(int do_skip)
{ {
z80_run(mcycles_vdp + MCYCLES_PER_LINE); z80_run(mcycles_vdp + MCYCLES_PER_LINE);
} }
else
{
Z80.cycles = mcycles_vdp + MCYCLES_PER_LINE;
}
/* run SVP chip */ /* run SVP chip */
if (svp) if (svp)
@ -826,10 +806,6 @@ void system_frame_scd(int do_skip)
{ {
z80_run(788); z80_run(788);
} }
else
{
Z80.cycles = 788;
}
/* set VINT flag */ /* set VINT flag */
status |= 0x80; status |= 0x80;
@ -854,10 +830,6 @@ void system_frame_scd(int do_skip)
{ {
z80_run(MCYCLES_PER_LINE); z80_run(MCYCLES_PER_LINE);
} }
else
{
Z80.cycles = MCYCLES_PER_LINE;
}
/* Z80 interrupt is cleared at the end of the line */ /* Z80 interrupt is cleared at the end of the line */
Z80.irq_state = CLEAR_LINE; Z80.irq_state = CLEAR_LINE;
@ -895,10 +867,6 @@ void system_frame_scd(int do_skip)
{ {
z80_run(mcycles_vdp + MCYCLES_PER_LINE); z80_run(mcycles_vdp + MCYCLES_PER_LINE);
} }
else
{
Z80.cycles = mcycles_vdp + MCYCLES_PER_LINE;
}
/* update VDP cycle count */ /* update VDP cycle count */
mcycles_vdp += MCYCLES_PER_LINE; mcycles_vdp += MCYCLES_PER_LINE;
@ -943,10 +911,6 @@ void system_frame_scd(int do_skip)
{ {
z80_run(mcycles_vdp + MCYCLES_PER_LINE); z80_run(mcycles_vdp + MCYCLES_PER_LINE);
} }
else
{
Z80.cycles = mcycles_vdp + MCYCLES_PER_LINE;
}
/* update VDP cycle count */ /* update VDP cycle count */
mcycles_vdp += MCYCLES_PER_LINE; mcycles_vdp += MCYCLES_PER_LINE;
@ -1003,10 +967,6 @@ void system_frame_scd(int do_skip)
{ {
z80_run(mcycles_vdp + MCYCLES_PER_LINE); z80_run(mcycles_vdp + MCYCLES_PER_LINE);
} }
else
{
Z80.cycles = mcycles_vdp + MCYCLES_PER_LINE;
}
/* update VDP cycle count */ /* update VDP cycle count */
mcycles_vdp += MCYCLES_PER_LINE; mcycles_vdp += MCYCLES_PER_LINE;

2
core/system.h
View File

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