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[Core/SCD] improved emulation accuracy of mirrored memory areas

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This commit is contained in:
EkeEke 2015-02-08 13:53:47 +01:00
parent c478c6026a
commit 5a3d4655ba
5 changed files with 471 additions and 182 deletions
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477
core/cd_hw/scd.c
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@ -149,13 +149,227 @@ static void prg_ram_write_word(unsigned int address, unsigned int data)
#endif #endif
} }
/*--------------------------------------------------------------------------*/
/* PRG-RAM bank mirrored access */
/*--------------------------------------------------------------------------*/
static unsigned int prg_ram_z80_read_byte(unsigned int address)
{
int offset = (address >> 16) & 0x03;
if (zbank_memory_map[offset].read)
{
return zbank_memory_map[offset].read(address);
}
return READ_BYTE(m68k.memory_map[offset].base, address & 0xffff);
}
static void prg_ram_z80_write_byte(unsigned int address, unsigned int data)
{
int offset = (address >> 16) & 0x03;
if (zbank_memory_map[offset].write)
{
zbank_memory_map[offset].write(address, data);
}
else
{
WRITE_BYTE(m68k.memory_map[offset].base, address & 0xffff, data);
}
}
static unsigned int prg_ram_m68k_read_byte(unsigned int address)
{
int offset = (address >> 16) & 0x03;
if (m68k.memory_map[offset].read8)
{
return m68k.memory_map[offset].read8(address);
}
return READ_BYTE(m68k.memory_map[offset].base, address & 0xffff);
}
static unsigned int prg_ram_m68k_read_word(unsigned int address)
{
int offset = (address >> 16) & 0x03;
if (m68k.memory_map[offset].read16)
{
return m68k.memory_map[offset].read16(address);
}
return *(uint16 *)(m68k.memory_map[offset].base + (address & 0xffff));
}
static void prg_ram_m68k_write_byte(unsigned int address, unsigned int data)
{
int offset = (address >> 16) & 0x03;
if (m68k.memory_map[offset].write8)
{
m68k.memory_map[offset].write8(address, data);
}
else
{
WRITE_BYTE(m68k.memory_map[offset].base, address & 0xffff, data);
}
}
static void prg_ram_m68k_write_word(unsigned int address, unsigned int data)
{
int offset = (address >> 16) & 0x03;
if (m68k.memory_map[offset].write16)
{
m68k.memory_map[offset].write16(address, data);
}
else
{
*(uint16 *)(m68k.memory_map[offset].base + (address & 0xffff)) = data;
}
}
/*--------------------------------------------------------------------------*/
/* Word-RAM bank mirrored access */
/*--------------------------------------------------------------------------*/
static unsigned int word_ram_z80_read_byte(unsigned int address)
{
int offset = (address >> 16) & 0x23;
if (zbank_memory_map[offset].read)
{
return zbank_memory_map[offset].read(address);
}
return READ_BYTE(m68k.memory_map[offset].base, address & 0xffff);
}
static void word_ram_z80_write_byte(unsigned int address, unsigned int data)
{
int offset = (address >> 16) & 0x23;
if (zbank_memory_map[offset].write)
{
zbank_memory_map[offset].write(address, data);
}
else
{
WRITE_BYTE(m68k.memory_map[offset].base, address & 0xffff, data);
}
}
static unsigned int word_ram_m68k_read_byte(unsigned int address)
{
int offset = (address >> 16) & 0x23;
if (m68k.memory_map[offset].read8)
{
return m68k.memory_map[offset].read8(address);
}
return READ_BYTE(m68k.memory_map[offset].base, address & 0xffff);
}
static unsigned int word_ram_m68k_read_word(unsigned int address)
{
int offset = (address >> 16) & 0x23;
if (m68k.memory_map[offset].read16)
{
return m68k.memory_map[offset].read16(address);
}
return *(uint16 *)(m68k.memory_map[offset].base + (address & 0xffff));
}
static void word_ram_m68k_write_byte(unsigned int address, unsigned int data)
{
int offset = (address >> 16) & 0x23;
if (m68k.memory_map[offset].write8)
{
m68k.memory_map[offset].write8(address, data);
}
else
{
WRITE_BYTE(m68k.memory_map[offset].base, address & 0xffff, data);
}
}
static void word_ram_m68k_write_word(unsigned int address, unsigned int data)
{
int offset = (address >> 16) & 0x23;
if (m68k.memory_map[offset].write16)
{
m68k.memory_map[offset].write16(address, data);
}
else
{
*(uint16 *)(m68k.memory_map[offset].base + (address & 0xffff)) = data;
}
}
static unsigned int word_ram_s68k_read_byte(unsigned int address)
{
int offset = (address >> 16) & 0x0f;
if (s68k.memory_map[offset].read8)
{
return s68k.memory_map[offset].read8(address);
}
return READ_BYTE(s68k.memory_map[offset].base, address & 0xffff);
}
static unsigned int word_ram_s68k_read_word(unsigned int address)
{
int offset = (address >> 16) & 0x0f;
if (s68k.memory_map[offset].read16)
{
return s68k.memory_map[offset].read16(address);
}
return *(uint16 *)(s68k.memory_map[offset].base + (address & 0xffff));
}
static void word_ram_s68k_write_byte(unsigned int address, unsigned int data)
{
int offset = (address >> 16) & 0x0f;
if (s68k.memory_map[offset].write8)
{
s68k.memory_map[offset].write8(address, data);
}
else
{
WRITE_BYTE(s68k.memory_map[offset].base, address & 0xffff, data);
}
}
static void word_ram_s68k_write_word(unsigned int address, unsigned int data)
{
int offset = (address >> 16) & 0x0f;
if (s68k.memory_map[offset].write16)
{
s68k.memory_map[offset].write16(address, data);
}
else
{
*(uint16 *)(s68k.memory_map[offset].base + (address & 0xffff)) = data;
}
}
/*--------------------------------------------------------------------------*/ /*--------------------------------------------------------------------------*/
/* internal backup RAM (8KB) */ /* internal backup RAM (8KB) */
/*--------------------------------------------------------------------------*/ /*--------------------------------------------------------------------------*/
static unsigned int bram_read_byte(unsigned int address) static unsigned int bram_read_byte(unsigned int address)
{ {
/* LSB only */ /* LSB only */
if (address & 1) if (address & 0x01)
{ {
return scd.bram[(address >> 1) & 0x1fff]; return scd.bram[(address >> 1) & 0x1fff];
} }
@ -171,7 +385,7 @@ static unsigned int bram_read_word(unsigned int address)
static void bram_write_byte(unsigned int address, unsigned int data) static void bram_write_byte(unsigned int address, unsigned int data)
{ {
/* LSB only */ /* LSB only */
if (address & 1) if (address & 0x01)
{ {
scd.bram[(address >> 1) & 0x1fff] = data; scd.bram[(address >> 1) & 0x1fff] = data;
} }
@ -183,7 +397,7 @@ static void bram_write_word(unsigned int address, unsigned int data)
} }
/*--------------------------------------------------------------------------*/ /*--------------------------------------------------------------------------*/
/* PCM chip & Gate-Array area */ /* SUB-CPU polling detection and MAIN-CPU synchronization */
/*--------------------------------------------------------------------------*/ /*--------------------------------------------------------------------------*/
static void s68k_poll_detect(unsigned int reg_mask) static void s68k_poll_detect(unsigned int reg_mask)
@ -255,6 +469,10 @@ static void s68k_poll_sync(unsigned int reg_mask)
m68k.poll.detected &= ~reg_mask; m68k.poll.detected &= ~reg_mask;
} }
/*--------------------------------------------------------------------------*/
/* PCM chip & Gate-Array area */
/*--------------------------------------------------------------------------*/
static unsigned int scd_read_byte(unsigned int address) static unsigned int scd_read_byte(unsigned int address)
{ {
/* PCM area (8K) is mirrored into $FF0000-$FF7FFF */ /* PCM area (8K) is mirrored into $FF0000-$FF7FFF */
@ -474,11 +692,15 @@ INLINE void word_ram_switch(uint8 mode)
*ptr1++=*ptr3++; *ptr1++=*ptr3++;
} }
/* allow Word-RAM access from both CPU in 2M mode (fixes sync issues in Mortal Kombat) */ /* MAIN-CPU: $200000-$21FFFF is mapped to 256K Word-RAM (lower 128K) */
for (i=scd.cartridge.boot+0x20; i<scd.cartridge.boot+0x24; i++) for (i=scd.cartridge.boot+0x20; i<scd.cartridge.boot+0x22; i++)
{ {
/* MAIN-CPU: $200000-$23FFFF is mapped to 256K Word-RAM */
m68k.memory_map[i].base = scd.word_ram_2M + ((i & 0x03) << 16); m68k.memory_map[i].base = scd.word_ram_2M + ((i & 0x03) << 16);
}
/* MAIN-CPU: $220000-$23FFFF is mapped to 256K Word-RAM (upper 128K) */
for (i=scd.cartridge.boot+0x22; i<scd.cartridge.boot+0x24; i++)
{
m68k.memory_map[i].read8 = NULL; m68k.memory_map[i].read8 = NULL;
m68k.memory_map[i].read16 = NULL; m68k.memory_map[i].read16 = NULL;
m68k.memory_map[i].write8 = NULL; m68k.memory_map[i].write8 = NULL;
@ -487,18 +709,18 @@ INLINE void word_ram_switch(uint8 mode)
zbank_memory_map[i].write = NULL; zbank_memory_map[i].write = NULL;
} }
/* SUB-CPU: $080000-$0BFFFF is mapped to 256K Word-RAM */
for (i=0x08; i<0x0c; i++) for (i=0x08; i<0x0c; i++)
{ {
/* SUB-CPU: $080000-$0BFFFF is mapped to 256K Word-RAM */
s68k.memory_map[i].read8 = NULL; s68k.memory_map[i].read8 = NULL;
s68k.memory_map[i].read16 = NULL; s68k.memory_map[i].read16 = NULL;
s68k.memory_map[i].write8 = NULL; s68k.memory_map[i].write8 = NULL;
s68k.memory_map[i].write16 = NULL; s68k.memory_map[i].write16 = NULL;
} }
/* SUB-CPU: $0C0000-$0DFFFF is unmapped */
for (i=0x0c; i<0x0e; i++) for (i=0x0c; i<0x0e; i++)
{ {
/* SUB-CPU: $0C0000-$0DFFFF is unmapped */
s68k.memory_map[i].read8 = s68k_read_bus_8; s68k.memory_map[i].read8 = s68k_read_bus_8;
s68k.memory_map[i].read16 = s68k_read_bus_16; s68k.memory_map[i].read16 = s68k_read_bus_16;
s68k.memory_map[i].write8 = s68k_unused_8_w; s68k.memory_map[i].write8 = s68k_unused_8_w;
@ -1067,7 +1289,6 @@ static void scd_write_word(unsigned int address, unsigned int data)
} }
} }
void scd_init(void) void scd_init(void)
{ {
int i; int i;
@ -1076,45 +1297,49 @@ void scd_init(void)
/* MAIN-CPU low memory map ($000000-$7FFFFF) */ /* MAIN-CPU low memory map ($000000-$7FFFFF) */
/****************************************************************/ /****************************************************************/
/* 0x00: boot from CD (Mode 2), 0x40: boot from cartridge (Mode 1) */ /* 0x00: boot from CD (default) */
uint8 base = scd.cartridge.boot; /* 0x40: boot from cartridge (mode 1) when /CART is asserted */
int base = scd.cartridge.boot;
/* $400000-$7FFFFF (resp. $000000-$3FFFFF): cartridge area (4MB) */ /* $400000-$7FFFFF (resp. $000000-$3FFFFF): cartridge port (/CE0 asserted) */
cd_cart_init(); cd_cart_init();
/* $000000-$1FFFFF (resp. $400000-$5FFFFF): CD memory area */ /* $000000-$1FFFFF (resp. $400000-$5FFFFF): expansion port (/ROM asserted) */
for (i=base; i<base+0x20; i++) for (i=base+0x00; i<base+0x20; i++)
{ {
if (i & 2) /* only VA1-VA17 are connected to expansion port */
switch (i & 0x02)
{ {
/* $020000-$03FFFF (resp. $420000-$43FFFF): PRG-RAM (first 128KB bank, mirrored each 256KB) */ case 0x00:
m68k.memory_map[i].base = scd.prg_ram + ((i & 1) << 16);
m68k.memory_map[i].read8 = NULL;
m68k.memory_map[i].read16 = NULL;
m68k.memory_map[i].write8 = NULL;
m68k.memory_map[i].write16 = NULL;
zbank_memory_map[i].read = NULL;
zbank_memory_map[i].write = NULL;
}
else
{ {
/* $000000-$01FFFF (resp. $400000-$41FFFF): internal ROM (128KB, mirrored each 256KB) */ /* $000000-$01FFFF (resp. $400000-$41FFFF): internal ROM (128KB), mirrored every 256KB up to $1FFFFF (resp. $5FFFFF) */
/* NB: Flux expects it to be mapped at $440000-$45FFFF */ m68k.memory_map[i].base = scd.bootrom + ((i & 0x01) << 16);
m68k.memory_map[i].base = scd.bootrom + ((i & 1) << 16);
m68k.memory_map[i].read8 = NULL; m68k.memory_map[i].read8 = NULL;
m68k.memory_map[i].read16 = NULL; m68k.memory_map[i].read16 = NULL;
m68k.memory_map[i].write8 = m68k_unused_8_w; m68k.memory_map[i].write8 = m68k_unused_8_w;
m68k.memory_map[i].write16 = m68k_unused_16_w; m68k.memory_map[i].write16 = m68k_unused_16_w;
zbank_memory_map[i].read = NULL; zbank_memory_map[i].read = NULL;
zbank_memory_map[i].write = zbank_unused_w; zbank_memory_map[i].write = zbank_unused_w;
} break;
} }
/* $200000-$3FFFFF (resp. $600000-$7FFFFF): Word-RAM in 2M mode (256KB mirrored) */ case 0x02:
for (i=base+0x20; i<base+0x40; i++) {
/* $020000-$03FFFF (resp. $420000-$43FFFF): PRG-RAM (first 128KB bank), mirrored every 256KB up to $1FFFFF (resp. $5FFFFF) */
m68k.memory_map[i].base = scd.prg_ram + ((i & 0x01) << 16);
/* automatic mirrored range remapping when switching PRG-RAM banks */
if (i > (base + 0x03))
{
m68k.memory_map[i].read8 = prg_ram_m68k_read_byte;
m68k.memory_map[i].read16 = prg_ram_m68k_read_word;
m68k.memory_map[i].write8 = prg_ram_m68k_write_byte;
m68k.memory_map[i].write16 = prg_ram_m68k_write_word;
zbank_memory_map[i].read = prg_ram_z80_read_byte;
zbank_memory_map[i].write = prg_ram_z80_write_byte;
}
else
{ {
m68k.memory_map[i].base = scd.word_ram_2M + ((i & 3) << 16);
m68k.memory_map[i].read8 = NULL; m68k.memory_map[i].read8 = NULL;
m68k.memory_map[i].read16 = NULL; m68k.memory_map[i].read16 = NULL;
m68k.memory_map[i].write8 = NULL; m68k.memory_map[i].write8 = NULL;
@ -1122,59 +1347,140 @@ void scd_init(void)
zbank_memory_map[i].read = NULL; zbank_memory_map[i].read = NULL;
zbank_memory_map[i].write = NULL; zbank_memory_map[i].write = NULL;
} }
break;
}
}
}
/* $200000-$3FFFFF (resp. $600000-$7FFFFF): expansion port (/RAS2 asserted) */
for (i=base+0x20; i<base+0x40; i++)
{
/* $200000-$23FFFF (resp. $600000-$63FFFF): Word-RAM in 2M mode (256KB), mirrored up to $3FFFFF (resp. $7FFFFF) */
m68k.memory_map[i].base = scd.word_ram_2M + ((i & 0x03) << 16);
/* automatic mirrored range remapping when switching Word-RAM */
if (i > (base + 0x23))
{
m68k.memory_map[i].read8 = word_ram_m68k_read_byte;
m68k.memory_map[i].read16 = word_ram_m68k_read_word;
m68k.memory_map[i].write8 = word_ram_m68k_write_byte;
m68k.memory_map[i].write16 = word_ram_m68k_write_word;
zbank_memory_map[i].read = word_ram_z80_read_byte;
zbank_memory_map[i].write = word_ram_z80_write_byte;
}
else
{
m68k.memory_map[i].read8 = NULL;
m68k.memory_map[i].read16 = NULL;
m68k.memory_map[i].write8 = NULL;
m68k.memory_map[i].write16 = NULL;
zbank_memory_map[i].read = NULL;
zbank_memory_map[i].write = NULL;
}
}
/****************************************************************/ /****************************************************************/
/* SUB-CPU memory map ($000000-$FFFFFF) */ /* SUB-CPU memory map ($000000-$FFFFFF) */
/****************************************************************/ /****************************************************************/
/* $000000-$07FFFF: PRG-RAM (512KB) */ for (i=0x00; i<0x100; i++)
for (i=0x00; i<0x08; i++)
{ {
s68k.memory_map[i].base = scd.prg_ram + (i << 16); /* only A1-A19 are connected to SUB-CPU */
switch (i & 0x0f)
{
case 0x00:
case 0x01:
case 0x02:
case 0x03:
case 0x04:
case 0x05:
case 0x06:
case 0x07:
{
/* $000000-$07FFFF (mirrored every 1MB): PRG-RAM (512KB) */
s68k.memory_map[i].base = scd.prg_ram + ((i & 0x07) << 16);
s68k.memory_map[i].read8 = NULL; s68k.memory_map[i].read8 = NULL;
s68k.memory_map[i].read16 = NULL; s68k.memory_map[i].read16 = NULL;
/* first 128KB is write-protected */ /* first 128KB can be write-protected */
s68k.memory_map[i].write8 = (i < 0x02) ? prg_ram_write_byte : NULL; s68k.memory_map[i].write8 = (i & 0x0e) ? NULL : prg_ram_write_byte;
s68k.memory_map[i].write16 = (i < 0x02) ? prg_ram_write_word : NULL; s68k.memory_map[i].write16 = (i & 0x0e) ? NULL : prg_ram_write_word;
break;
} }
/* $080000-$0BFFFF: Word-RAM in 2M mode (256KB)*/ case 0x08:
for (i=0x08; i<0x0c; i++) case 0x09:
case 0x0a:
case 0x0b:
{
/* $080000-$0BFFFF (mirrored every 1MB): Word-RAM in 2M mode (256KB)*/
s68k.memory_map[i].base = scd.word_ram_2M + ((i & 0x03) << 16);
/* automatic mirrored range remapping when switching Word-RAM */
if (i > 0x0f)
{
s68k.memory_map[i].read8 = word_ram_s68k_read_byte;
s68k.memory_map[i].read16 = word_ram_s68k_read_word;
s68k.memory_map[i].write8 = word_ram_s68k_write_byte;
s68k.memory_map[i].write16 = word_ram_s68k_write_word;
}
else
{ {
s68k.memory_map[i].base = scd.word_ram_2M + ((i & 3) << 16);
s68k.memory_map[i].read8 = NULL; s68k.memory_map[i].read8 = NULL;
s68k.memory_map[i].read16 = NULL; s68k.memory_map[i].read16 = NULL;
s68k.memory_map[i].write8 = NULL; s68k.memory_map[i].write8 = NULL;
s68k.memory_map[i].write16 = NULL; s68k.memory_map[i].write16 = NULL;
} }
break;
}
/* $0C0000-$FD0000: Unused area (Word-RAM mirrored ?) */ case 0x0c:
for (i=0x0c; i<0xfd; i++) case 0x0d:
{
/* $0C0000-$0DFFFF (mirrored every 1MB): unused in 2M mode (?) */
s68k.memory_map[i].base = scd.word_ram_2M + ((i & 0x03) << 16);
/* automatic mirrored range remapping when switching Word-RAM */
if (i > 0x0f)
{
s68k.memory_map[i].read8 = word_ram_s68k_read_byte;
s68k.memory_map[i].read16 = word_ram_s68k_read_word;
s68k.memory_map[i].write8 = word_ram_s68k_write_byte;
s68k.memory_map[i].write16 = word_ram_s68k_write_word;
}
else
{ {
s68k.memory_map[i].base = scd.word_ram_2M + ((i & 3) << 16);
s68k.memory_map[i].read8 = s68k_read_bus_8; s68k.memory_map[i].read8 = s68k_read_bus_8;
s68k.memory_map[i].read16 = s68k_read_bus_16; s68k.memory_map[i].read16 = s68k_read_bus_16;
s68k.memory_map[i].write8 = s68k_unused_8_w; s68k.memory_map[i].write8 = s68k_unused_8_w;
s68k.memory_map[i].write16 = s68k_unused_16_w; s68k.memory_map[i].write16 = s68k_unused_16_w;
} }
break;
}
/* $FD0000-$FF0000 (odd address only): 8KB backup RAM, mirrored(Wonder Mega / X'Eye BIOS access it at $FD0000-$FD1FFF) */ case 0x0e:
for (i=0xfd; i<0xff; i++)
{ {
/* $FE0000-$FEFFFF (mirrored every 1MB): 8KB backup RAM (Wonder Mega / X'Eye BIOS access it at $FD0000-$FD1FFF ?) */
s68k.memory_map[i].base = NULL; s68k.memory_map[i].base = NULL;
s68k.memory_map[i].read8 = bram_read_byte; s68k.memory_map[i].read8 = bram_read_byte;
s68k.memory_map[i].read16 = bram_read_word; s68k.memory_map[i].read16 = bram_read_word;
s68k.memory_map[i].write8 = bram_write_byte; s68k.memory_map[i].write8 = bram_write_byte;
s68k.memory_map[i].write16 = bram_write_word; s68k.memory_map[i].write16 = bram_write_word;
break;
} }
/* $FF0000-$FFFFFF: PCM hardware & SUB-CPU registers */ case 0x0f:
s68k.memory_map[0xff].base = NULL; {
s68k.memory_map[0xff].read8 = scd_read_byte; /* $FF0000-$FFFFFF (mirrored every 1MB): PCM hardware & SUB-CPU registers */
s68k.memory_map[0xff].read16 = scd_read_word; s68k.memory_map[i].base = NULL;
s68k.memory_map[0xff].write8 = scd_write_byte; s68k.memory_map[i].read8 = scd_read_byte;
s68k.memory_map[0xff].write16 = scd_write_word; s68k.memory_map[i].read16 = scd_read_word;
s68k.memory_map[i].write8 = scd_write_byte;
s68k.memory_map[i].write16 = scd_write_word;
break;
}
}
}
/* Initialize CD hardware */ /* Initialize CD hardware */
cdc_init(); cdc_init();
@ -1192,8 +1498,6 @@ void scd_reset(int hard)
/* TODO: figure what exactly is resetted when RESET bit is cleared by SUB-CPU */ /* TODO: figure what exactly is resetted when RESET bit is cleared by SUB-CPU */
if (hard) if (hard)
{ {
int i;
/* Clear all ASIC registers by default */ /* Clear all ASIC registers by default */
memset(scd.regs, 0, sizeof(scd.regs)); memset(scd.regs, 0, sizeof(scd.regs));
@ -1211,13 +1515,9 @@ void scd_reset(int hard)
/* 2M mode */ /* 2M mode */
word_ram_switch(0); word_ram_switch(0);
/* reset PRG-RAM banking on MAIN-CPU side */ /* reset PRG-RAM bank on MAIN-CPU side */
for (i=scd.cartridge.boot+0x02; i<scd.cartridge.boot+0x20; i+=4) m68k.memory_map[scd.cartridge.boot + 0x02].base = scd.prg_ram;
{ m68k.memory_map[scd.cartridge.boot + 0x03].base = scd.prg_ram + 0x10000;
/* MAIN-CPU: $020000-$03FFFF (resp. $420000-$43FFFF) mapped to first 128KB PRG-RAM bank (mirrored each 256KB) */
m68k.memory_map[i].base = scd.prg_ram;
m68k.memory_map[i+1].base = scd.prg_ram + 0x10000;
}
/* reset & halt SUB-CPU */ /* reset & halt SUB-CPU */
s68k.cycles = 0; s68k.cycles = 0;
@ -1475,34 +1775,28 @@ int scd_context_load(uint8 *state)
/* PRG-RAM */ /* PRG-RAM */
load_param(scd.prg_ram, sizeof(scd.prg_ram)); load_param(scd.prg_ram, sizeof(scd.prg_ram));
/* PRG-RAM can only be accessed from MAIN 68K & Z80 when SUB-CPU is halted (Dungeon Explorer USA version) */ /* PRG-RAM 128K bank mapped on MAIN-CPU side */
m68k.memory_map[scd.cartridge.boot + 0x02].base = scd.prg_ram + ((scd.regs[0x03>>1].byte.l & 0xc0) << 11);
m68k.memory_map[scd.cartridge.boot + 0x03].base = m68k.memory_map[scd.cartridge.boot + 0x02].base + 0x10000;
/* PRG-RAM can only be accessed from MAIN 68K & Z80 if SUB-CPU is halted (Dungeon Explorer USA version) */
if ((scd.regs[0x00].byte.l & 0x03) != 0x01) if ((scd.regs[0x00].byte.l & 0x03) != 0x01)
{ {
/* $020000-$03FFFF (resp. $420000-$43FFFF) is mapped to PRG-RAM 128K bank (mirrored every 256 KB) */ m68k.memory_map[scd.cartridge.boot + 0x02].read8 = m68k.memory_map[scd.cartridge.boot + 0x03].read8 = NULL;
for (i=scd.cartridge.boot+0x02; i<scd.cartridge.boot+0x20; i+=4) m68k.memory_map[scd.cartridge.boot + 0x02].read16 = m68k.memory_map[scd.cartridge.boot + 0x03].read16 = NULL;
{ m68k.memory_map[scd.cartridge.boot + 0x02].write8 = m68k.memory_map[scd.cartridge.boot + 0x03].write8 = NULL;
m68k.memory_map[i].base = m68k.memory_map[i+1].base = scd.prg_ram + ((scd.regs[0x03>>1].byte.l & 0xc0) << 11); m68k.memory_map[scd.cartridge.boot + 0x02].write16 = m68k.memory_map[scd.cartridge.boot + 0x03].write16 = NULL;
m68k.memory_map[i].read8 = m68k.memory_map[i+1].read8 = NULL; zbank_memory_map[scd.cartridge.boot + 0x02].read = zbank_memory_map[scd.cartridge.boot + 0x03].read = NULL;
m68k.memory_map[i].read16 = m68k.memory_map[i+1].read16 = NULL; zbank_memory_map[scd.cartridge.boot + 0x02].write = zbank_memory_map[scd.cartridge.boot + 0x03].write = NULL;
m68k.memory_map[i].write8 = m68k.memory_map[i+1].write8 = NULL;
m68k.memory_map[i].write16 = m68k.memory_map[i+1].write16 = NULL;
zbank_memory_map[i].read = zbank_memory_map[i+1].read = NULL;
zbank_memory_map[i].write = zbank_memory_map[i+1].write = NULL;
}
} }
else else
{ {
/* $020000-$03FFFF (resp. $420000-$43FFFF) is not mapped (mirrored every 256 KB) */ m68k.memory_map[scd.cartridge.boot + 0x02].read8 = m68k.memory_map[scd.cartridge.boot + 0x03].read8 = m68k_read_bus_8;
for (i=scd.cartridge.boot+0x02; i<scd.cartridge.boot+0x20; i+=4) m68k.memory_map[scd.cartridge.boot + 0x02].read16 = m68k.memory_map[scd.cartridge.boot + 0x03].read16 = m68k_read_bus_16;
{ m68k.memory_map[scd.cartridge.boot + 0x02].write8 = m68k.memory_map[scd.cartridge.boot + 0x03].write8 = m68k_unused_8_w;
m68k.memory_map[i].base = m68k.memory_map[i+1].base = scd.prg_ram + ((scd.regs[0x03>>1].byte.l & 0xc0) << 11); m68k.memory_map[scd.cartridge.boot + 0x02].write16 = m68k.memory_map[scd.cartridge.boot + 0x03].write16 = m68k_unused_16_w;
m68k.memory_map[i].read8 = m68k.memory_map[i+1].read8 = m68k_read_bus_8; zbank_memory_map[scd.cartridge.boot + 0x02].read = zbank_memory_map[scd.cartridge.boot + 0x03].read = zbank_unused_r;
m68k.memory_map[i].read16 = m68k.memory_map[i+1].read16 = m68k_read_bus_16; zbank_memory_map[scd.cartridge.boot + 0x02].write = zbank_memory_map[scd.cartridge.boot + 0x03].write = zbank_unused_w;
m68k.memory_map[i].write8 = m68k.memory_map[i+1].write8 = m68k_unused_8_w;
m68k.memory_map[i].write16 = m68k.memory_map[i+1].write16 = m68k_unused_16_w;
zbank_memory_map[i].read = zbank_memory_map[i+1].read = zbank_unused_r;
zbank_memory_map[i].write = zbank_memory_map[i+1].write = zbank_unused_w;
}
} }
/* Word-RAM */ /* Word-RAM */
@ -1597,10 +1891,15 @@ int scd_context_load(uint8 *state)
/* 2M mode */ /* 2M mode */
load_param(scd.word_ram_2M, sizeof(scd.word_ram_2M)); load_param(scd.word_ram_2M, sizeof(scd.word_ram_2M));
for (i=scd.cartridge.boot+0x20; i<scd.cartridge.boot+0x24; i++) /* MAIN-CPU: $200000-$21FFFF is mapped to 256K Word-RAM (upper 128K) */
for (i=scd.cartridge.boot+0x20; i<scd.cartridge.boot+0x22; i++)
{ {
/* MAIN-CPU: $200000-$23FFFF is mapped to 256K Word-RAM */
m68k.memory_map[i].base = scd.word_ram_2M + ((i & 0x03) << 16); m68k.memory_map[i].base = scd.word_ram_2M + ((i & 0x03) << 16);
}
/* MAIN-CPU: $220000-$23FFFF is mapped to 256K Word-RAM (lower 128K) */
for (i=scd.cartridge.boot+0x22; i<scd.cartridge.boot+0x24; i++)
{
m68k.memory_map[i].read8 = NULL; m68k.memory_map[i].read8 = NULL;
m68k.memory_map[i].read16 = NULL; m68k.memory_map[i].read16 = NULL;
m68k.memory_map[i].write8 = NULL; m68k.memory_map[i].write8 = NULL;
@ -1609,18 +1908,18 @@ int scd_context_load(uint8 *state)
zbank_memory_map[i].write = NULL; zbank_memory_map[i].write = NULL;
} }
/* SUB-CPU: $080000-$0BFFFF is mapped to 256K Word-RAM */
for (i=0x08; i<0x0c; i++) for (i=0x08; i<0x0c; i++)
{ {
/* SUB-CPU: $080000-$0BFFFF is mapped to 256K Word-RAM */
s68k.memory_map[i].read8 = NULL; s68k.memory_map[i].read8 = NULL;
s68k.memory_map[i].read16 = NULL; s68k.memory_map[i].read16 = NULL;
s68k.memory_map[i].write8 = NULL; s68k.memory_map[i].write8 = NULL;
s68k.memory_map[i].write16 = NULL; s68k.memory_map[i].write16 = NULL;
} }
/* SUB-CPU: $0C0000-$0DFFFF is unmapped */
for (i=0x0c; i<0x0e; i++) for (i=0x0c; i<0x0e; i++)
{ {
/* SUB-CPU: $0C0000-$0DFFFF is unmapped */
s68k.memory_map[i].read8 = s68k_read_bus_8; s68k.memory_map[i].read8 = s68k_read_bus_8;
s68k.memory_map[i].read16 = s68k_read_bus_16; s68k.memory_map[i].read16 = s68k_read_bus_16;
s68k.memory_map[i].write8 = s68k_unused_8_w; s68k.memory_map[i].write8 = s68k_unused_8_w;

76
core/mem68k.c
View File

@ -220,7 +220,7 @@ void z80_write_word(unsigned int address, unsigned int data)
/*--------------------------------------------------------------------------*/ /*--------------------------------------------------------------------------*/
/* I/O Control */ /* MAIN-CPU polling detection and SUB-CPU synchronization (MEGA CD mode) */
/*--------------------------------------------------------------------------*/ /*--------------------------------------------------------------------------*/
static void m68k_poll_detect(unsigned int reg_mask) static void m68k_poll_detect(unsigned int reg_mask)
@ -292,6 +292,10 @@ static void m68k_poll_sync(unsigned int reg_mask)
m68k.poll.detected &= ~reg_mask; m68k.poll.detected &= ~reg_mask;
} }
/*--------------------------------------------------------------------------*/
/* I/O Control */
/*--------------------------------------------------------------------------*/
unsigned int ctrl_io_read_byte(unsigned int address) unsigned int ctrl_io_read_byte(unsigned int address)
{ {
switch ((address >> 8) & 0xFF) switch ((address >> 8) & 0xFF)
@ -679,34 +683,27 @@ void ctrl_io_write_byte(unsigned int address, unsigned int data)
/* check if SUB-CPU halt status has changed */ /* check if SUB-CPU halt status has changed */
if (s68k.stopped != halted) if (s68k.stopped != halted)
{ {
int i; /* PRG-RAM (128KB bank) is normally mapped to $020000-$03FFFF (resp. $420000-$43FFFF) */
unsigned int base = scd.cartridge.boot + 0x02;
/* PRG-RAM can only be accessed from MAIN 68K & Z80 when SUB-CPU is halted (Dungeon Explorer USA version) */ /* PRG-RAM can only be accessed from MAIN 68K & Z80 when SUB-CPU is halted (Dungeon Explorer USA version) */
if ((data & 0x03) != 0x01) if ((data & 0x03) != 0x01)
{ {
/* $020000-$03FFFF (resp. $420000-$43FFFF) is mapped to PRG-RAM 128K bank (mirrored every 256 KB) */ m68k.memory_map[base].read8 = m68k.memory_map[base+1].read8 = NULL;
for (i=scd.cartridge.boot+0x02; i<scd.cartridge.boot+0x20; i+=4) m68k.memory_map[base].read16 = m68k.memory_map[base+1].read16 = NULL;
{ m68k.memory_map[base].write8 = m68k.memory_map[base+1].write8 = NULL;
m68k.memory_map[i].read8 = m68k.memory_map[i+1].read8 = NULL; m68k.memory_map[base].write16 = m68k.memory_map[base+1].write16 = NULL;
m68k.memory_map[i].read16 = m68k.memory_map[i+1].read16 = NULL; zbank_memory_map[base].read = zbank_memory_map[base+1].read = NULL;
m68k.memory_map[i].write8 = m68k.memory_map[i+1].write8 = NULL; zbank_memory_map[base].write = zbank_memory_map[base+1].write = NULL;
m68k.memory_map[i].write16 = m68k.memory_map[i+1].write16 = NULL;
zbank_memory_map[i].read = zbank_memory_map[i+1].read = NULL;
zbank_memory_map[i].write = zbank_memory_map[i+1].write = NULL;
}
} }
else else
{ {
/* $020000-$03FFFF (resp. $420000-$43FFFF) is not mapped (mirrored every 256 KB) */ m68k.memory_map[base].read8 = m68k.memory_map[base+1].read8 = m68k_read_bus_8;
for (i=scd.cartridge.boot+0x02; i<scd.cartridge.boot+0x20; i+=4) m68k.memory_map[base].read16 = m68k.memory_map[base+1].read16 = m68k_read_bus_16;
{ m68k.memory_map[base].write8 = m68k.memory_map[base+1].write8 = m68k_unused_8_w;
m68k.memory_map[i].read8 = m68k.memory_map[i+1].read8 = m68k_read_bus_8; m68k.memory_map[base].write16 = m68k.memory_map[base+1].write16 = m68k_unused_16_w;
m68k.memory_map[i].read16 = m68k.memory_map[i+1].read16 = m68k_read_bus_16; zbank_memory_map[base].read = zbank_memory_map[base+1].read = zbank_unused_r;
m68k.memory_map[i].write8 = m68k.memory_map[i+1].write8 = m68k_unused_8_w; zbank_memory_map[base].write = zbank_memory_map[base+1].write = zbank_unused_w;
m68k.memory_map[i].write16 = m68k.memory_map[i+1].write16 = m68k_unused_16_w;
zbank_memory_map[i].read = zbank_memory_map[i+1].read = zbank_unused_r;
zbank_memory_map[i].write = zbank_memory_map[i+1].write = zbank_unused_w;
}
} }
} }
@ -911,34 +908,27 @@ void ctrl_io_write_word(unsigned int address, unsigned int data)
/* check if SUB-CPU halt status has changed */ /* check if SUB-CPU halt status has changed */
if (s68k.stopped != halted) if (s68k.stopped != halted)
{ {
int i; /* PRG-RAM (128KB bank) is normally mapped to $020000-$03FFFF (resp. $420000-$43FFFF) */
unsigned int base = scd.cartridge.boot + 0x02;
/* PRG-RAM can only be accessed from MAIN 68K & Z80 when SUB-CPU is halted (Dungeon Explorer USA version) */ /* PRG-RAM can only be accessed from MAIN 68K & Z80 when SUB-CPU is halted (Dungeon Explorer USA version) */
if ((data & 0x03) != 0x01) if ((data & 0x03) != 0x01)
{ {
/* $020000-$03FFFF (resp. $420000-$43FFFF) is mapped to PRG-RAM 128K bank (mirrored every 256 KB) */ m68k.memory_map[base].read8 = m68k.memory_map[base+1].read8 = NULL;
for (i=scd.cartridge.boot+0x02; i<scd.cartridge.boot+0x20; i+=4) m68k.memory_map[base].read16 = m68k.memory_map[base+1].read16 = NULL;
{ m68k.memory_map[base].write8 = m68k.memory_map[base+1].write8 = NULL;
m68k.memory_map[i].read8 = m68k.memory_map[i+1].read8 = NULL; m68k.memory_map[base].write16 = m68k.memory_map[base+1].write16 = NULL;
m68k.memory_map[i].read16 = m68k.memory_map[i+1].read16 = NULL; zbank_memory_map[base].read = zbank_memory_map[base+1].read = NULL;
m68k.memory_map[i].write8 = m68k.memory_map[i+1].write8 = NULL; zbank_memory_map[base].write = zbank_memory_map[base+1].write = NULL;
m68k.memory_map[i].write16 = m68k.memory_map[i+1].write16 = NULL;
zbank_memory_map[i].read = zbank_memory_map[i+1].read = NULL;
zbank_memory_map[i].write = zbank_memory_map[i+1].write = NULL;
}
} }
else else
{ {
/* $020000-$03FFFF (resp. $420000-$43FFFF) is not mapped (mirrored every 256 KB) */ m68k.memory_map[base].read8 = m68k.memory_map[base+1].read8 = m68k_read_bus_8;
for (i=scd.cartridge.boot+0x02; i<scd.cartridge.boot+0x20; i+=4) m68k.memory_map[base].read16 = m68k.memory_map[base+1].read16 = m68k_read_bus_16;
{ m68k.memory_map[base].write8 = m68k.memory_map[base+1].write8 = m68k_unused_8_w;
m68k.memory_map[i].read8 = m68k.memory_map[i+1].read8 = m68k_read_bus_8; m68k.memory_map[base].write16 = m68k.memory_map[base+1].write16 = m68k_unused_16_w;
m68k.memory_map[i].read16 = m68k.memory_map[i+1].read16 = m68k_read_bus_16; zbank_memory_map[base].read = zbank_memory_map[base+1].read = zbank_unused_r;
m68k.memory_map[i].write8 = m68k.memory_map[i+1].write8 = m68k_unused_8_w; zbank_memory_map[base].write = zbank_memory_map[base+1].write = zbank_unused_w;
m68k.memory_map[i].write16 = m68k.memory_map[i+1].write16 = m68k_unused_16_w;
zbank_memory_map[i].read = zbank_memory_map[i+1].read = zbank_unused_r;
zbank_memory_map[i].write = zbank_memory_map[i+1].write = zbank_unused_w;
}
} }
} }