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Improved timing of communication between the main and sound cpus in the megadriv driver.

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This commit is contained in:
Wilbert Pol 2009-05-22 13:17:57 +00:00
parent fb0923bdf3
commit 18ed233407
1 changed files with 27 additions and 24 deletions
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51
src/mame/drivers/megadriv.c
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@ -2242,6 +2242,30 @@ static READ16_HANDLER( megadriv_68k_check_z80_bus )
}
static TIMER_CALLBACK( megadriv_z80_run_state )
{
/* Is the z80 RESET line pulled? */
if ( genz80.z80_is_reset )
{
devtag_reset( machine, "genesis_snd_z80" );
cputag_suspend( machine, "genesis_snd_z80", SUSPEND_REASON_HALT, 1 );
devtag_reset( machine, "ym" );
}
else
{
/* Check if z80 has the bus */
if ( genz80.z80_has_bus )
{
cputag_resume( machine, "genesis_snd_z80", SUSPEND_REASON_HALT );
}
else
{
cputag_suspend( machine, "genesis_snd_z80", SUSPEND_REASON_HALT, 1 );
}
}
}
static WRITE16_HANDLER( megadriv_68k_req_z80_bus )
{
/* Request the Z80 bus, allows 68k to read/write Z80 address space */
@ -2251,13 +2275,11 @@ static WRITE16_HANDLER( megadriv_68k_req_z80_bus )
{
//logerror("%06x: 68000 request z80 Bus (byte MSB access) %04x %04x\n", cpu_get_pc(space->cpu),data,mem_mask);
genz80.z80_has_bus = 0;
cputag_suspend( space->machine, "genesis_snd_z80", SUSPEND_REASON_HALT, 1 );
}
else
{
//logerror("%06x: 68000 return z80 Bus (byte MSB access) %04x %04x\n", cpu_get_pc(space->cpu),data,mem_mask);
genz80.z80_has_bus = 1;
cputag_resume( space->machine, "genesis_snd_z80", SUSPEND_REASON_HALT );
}
}
else if (!ACCESSING_BITS_8_15) // is this valid?
@ -2266,13 +2288,11 @@ static WRITE16_HANDLER( megadriv_68k_req_z80_bus )
{
//logerror("%06x: 68000 request z80 Bus (byte LSB access) %04x %04x\n", cpu_get_pc(space->cpu),data,mem_mask);
genz80.z80_has_bus = 0;
cputag_suspend( space->machine, "genesis_snd_z80", SUSPEND_REASON_HALT, 1 );
}
else
{
//logerror("%06x: 68000 return z80 Bus (byte LSB access) %04x %04x\n", cpu_get_pc(space->cpu),data,mem_mask);
genz80.z80_has_bus = 1;
cputag_resume( space->machine, "genesis_snd_z80", SUSPEND_REASON_HALT );
}
}
else // word access
@ -2281,15 +2301,14 @@ static WRITE16_HANDLER( megadriv_68k_req_z80_bus )
{
//logerror("%06x: 68000 request z80 Bus (word access) %04x %04x\n", cpu_get_pc(space->cpu),data,mem_mask);
genz80.z80_has_bus = 0;
cputag_suspend( space->machine, "genesis_snd_z80", SUSPEND_REASON_HALT, 1 );
}
else
{
//logerror("%06x: 68000 return z80 Bus (byte LSB access) %04x %04x\n", cpu_get_pc(space->cpu),data,mem_mask);
genz80.z80_has_bus = 1;
cputag_resume( space->machine, "genesis_snd_z80", SUSPEND_REASON_HALT );
}
}
timer_set( space->machine, attotime_zero, NULL, 0, megadriv_z80_run_state );
}
static WRITE16_HANDLER ( megadriv_68k_req_z80_reset )
@ -2300,16 +2319,11 @@ static WRITE16_HANDLER ( megadriv_68k_req_z80_reset )
{
//logerror("%06x: 68000 clear z80 reset (byte MSB access) %04x %04x\n", cpu_get_pc(space->cpu),data,mem_mask);
genz80.z80_is_reset = 0;
if ( genz80.z80_has_bus )
cputag_resume( space->machine, "genesis_snd_z80", SUSPEND_REASON_HALT );
}
else
{
//logerror("%06x: 68000 start z80 reset (byte MSB access) %04x %04x\n", cpu_get_pc(space->cpu),data,mem_mask);
genz80.z80_is_reset = 1;
device_reset( cputag_get_cpu(space->machine, "genesis_snd_z80") );
cputag_suspend( space->machine, "genesis_snd_z80", SUSPEND_REASON_HALT, 1 );
devtag_reset(space->machine, "ym");
}
}
else if (!ACCESSING_BITS_8_15) // is this valid?
@ -2318,17 +2332,11 @@ static WRITE16_HANDLER ( megadriv_68k_req_z80_reset )
{
//logerror("%06x: 68000 clear z80 reset (byte LSB access) %04x %04x\n", cpu_get_pc(space->cpu),data,mem_mask);
genz80.z80_is_reset = 0;
if ( genz80.z80_has_bus )
cputag_resume( space->machine, "genesis_snd_z80", SUSPEND_REASON_HALT );
}
else
{
//logerror("%06x: 68000 start z80 reset (byte LSB access) %04x %04x\n", cpu_get_pc(space->cpu),data,mem_mask);
genz80.z80_is_reset = 1;
device_reset( cputag_get_cpu(space->machine, "genesis_snd_z80") );
cputag_suspend( space->machine, "genesis_snd_z80", SUSPEND_REASON_HALT, 1 );
devtag_reset(space->machine, "ym");
}
}
else // word access
@ -2337,18 +2345,14 @@ static WRITE16_HANDLER ( megadriv_68k_req_z80_reset )
{
//logerror("%06x: 68000 clear z80 reset (word access) %04x %04x\n", cpu_get_pc(space->cpu),data,mem_mask);
genz80.z80_is_reset = 0;
if ( genz80.z80_has_bus )
cputag_resume( space->machine, "genesis_snd_z80", SUSPEND_REASON_HALT );
}
else
{
//logerror("%06x: 68000 start z80 reset (byte LSB access) %04x %04x\n", cpu_get_pc(space->cpu),data,mem_mask);
genz80.z80_is_reset = 1;
device_reset( cputag_get_cpu(space->machine, "genesis_snd_z80") );
cputag_suspend( space->machine, "genesis_snd_z80", SUSPEND_REASON_HALT, 1 );
devtag_reset(space->machine, "ym");
}
}
timer_set( space->machine, attotime_zero, NULL, 0, megadriv_z80_run_state );
}
static READ8_HANDLER( z80_read_68k_banked_data )
@ -5973,11 +5977,10 @@ MACHINE_RESET( megadriv )
if (cputag_get_cpu(machine, "genesis_snd_z80") != NULL)
{
genz80.z80_is_reset = 1;
cputag_set_input_line(machine, "genesis_snd_z80", INPUT_LINE_RESET, ASSERT_LINE);
genz80.z80_has_bus = 1;
cputag_set_input_line(machine, "genesis_snd_z80", INPUT_LINE_HALT, CLEAR_LINE);
genz80.z80_bank_addr = 0;
genesis_scanline_counter = -1;
timer_set( machine, attotime_zero, NULL, 0, megadriv_z80_run_state );
}
megadrive_imode = 0;