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[Core/CD] improved PCM chip & Gate-Array area mirroring

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This commit is contained in:
EkeEke 2015-05-31 20:39:53 +02:00
parent 304219da58
commit bbdb551faf
1 changed files with 32 additions and 26 deletions
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58
core/cd_hw/scd.c
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@ -475,8 +475,8 @@ static void s68k_poll_sync(unsigned int reg_mask)
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) mirrored into $xF0000-$xF7FFF */
if (address < 0xff8000) if (!(address & 0x8000))
{ {
/* get /LDS only */ /* get /LDS only */
if (address & 1) if (address & 1)
@ -491,36 +491,39 @@ static unsigned int scd_read_byte(unsigned int address)
error("[%d][%d]read byte CD register %X (%X)\n", v_counter, s68k.cycles, address, s68k.pc); error("[%d][%d]read byte CD register %X (%X)\n", v_counter, s68k.cycles, address, s68k.pc);
#endif #endif
/* only A1-A8 are used for decoding */
address &= 0x1ff;
/* Memory Mode */ /* Memory Mode */
if (address == 0xff8003) if (address == 0x03)
{ {
s68k_poll_detect(1<<0x03); s68k_poll_detect(1<<0x03);
return scd.regs[0x03>>1].byte.l; return scd.regs[0x03>>1].byte.l;
} }
/* MAIN-CPU communication flags */ /* MAIN-CPU communication flags */
if (address == 0xff800e) if (address == 0x0e)
{ {
s68k_poll_detect(1<<0x0e); s68k_poll_detect(1<<0x0e);
return scd.regs[0x0e>>1].byte.h; return scd.regs[0x0e>>1].byte.h;
} }
/* CDC transfer status */ /* CDC transfer status */
if (address == 0xff8004) if (address == 0x04)
{ {
s68k_poll_detect(1<<0x04); s68k_poll_detect(1<<0x04);
return scd.regs[0x04>>1].byte.h; return scd.regs[0x04>>1].byte.h;
} }
/* GFX operation status */ /* GFX operation status */
if (address == 0xff8058) if (address == 0x58)
{ {
s68k_poll_detect(1<<0x08); s68k_poll_detect(1<<0x08);
return scd.regs[0x58>>1].byte.h; return scd.regs[0x58>>1].byte.h;
} }
/* CDC register data (controlled by BIOS, byte access only ?) */ /* CDC register data (controlled by BIOS, byte access only ?) */
if (address == 0xff8007) if (address == 0x07)
{ {
unsigned int data = cdc_reg_r(); unsigned int data = cdc_reg_r();
#ifdef LOG_CDC #ifdef LOG_CDC
@ -530,21 +533,21 @@ static unsigned int scd_read_byte(unsigned int address)
} }
/* LED status */ /* LED status */
if (address == 0xff8000) if (address == 0x00)
{ {
/* register $00 is reserved for MAIN-CPU, we use $06 instead */ /* register $00 is reserved for MAIN-CPU, we use $06 instead */
return scd.regs[0x06>>1].byte.h; return scd.regs[0x06>>1].byte.h;
} }
/* RESET status */ /* RESET status */
if (address == 0xff8001) if (address == 0x01)
{ {
/* always return 1 */ /* always return 1 */
return 0x01; return 0x01;
} }
/* Font data */ /* Font data */
if ((address >= 0xff8050) && (address <= 0xff8056)) if ((address >= 0x50) && (address <= 0x56))
{ {
/* shifted 4-bit input (xxxx00) */ /* shifted 4-bit input (xxxx00) */
uint8 bits = (scd.regs[0x4e>>1].w >> (((address & 6) ^ 6) << 1)) << 2; uint8 bits = (scd.regs[0x4e>>1].w >> (((address & 6) ^ 6) << 1)) << 2;
@ -574,7 +577,7 @@ static unsigned int scd_read_byte(unsigned int address)
} }
/* Subcode buffer */ /* Subcode buffer */
else if (address >= 0xff8100) else if (address & 0x100)
{ {
/* 64 x 16-bit mirrored */ /* 64 x 16-bit mirrored */
address &= 0x17f; address &= 0x17f;
@ -584,17 +587,17 @@ static unsigned int scd_read_byte(unsigned int address)
if (address & 1) if (address & 1)
{ {
/* register LSB */ /* register LSB */
return scd.regs[(address >> 1) & 0xff].byte.l; return scd.regs[address >> 1].byte.l;
} }
/* register MSB */ /* register MSB */
return scd.regs[(address >> 1) & 0xff].byte.h; return scd.regs[address >> 1].byte.h;
} }
static unsigned int scd_read_word(unsigned int address) static unsigned int scd_read_word(unsigned int address)
{ {
/* PCM area (8K) is mirrored into $FF0000-$FF7FFF */ /* PCM area (8K) mirrored into $xF0000-$xF7FFF */
if (address < 0xff8000) if (!(address & 0x8000))
{ {
/* get /LDS only */ /* get /LDS only */
return pcm_read((address >> 1) & 0x1fff); return pcm_read((address >> 1) & 0x1fff);
@ -604,35 +607,38 @@ static unsigned int scd_read_word(unsigned int address)
error("[%d][%d]read word CD register %X (%X)\n", v_counter, s68k.cycles, address, s68k.pc); error("[%d][%d]read word CD register %X (%X)\n", v_counter, s68k.cycles, address, s68k.pc);
#endif #endif
/* only A1-A8 are used for decoding */
address &= 0x1ff;
/* Memory Mode */ /* Memory Mode */
if (address == 0xff8002) if (address == 0x02)
{ {
s68k_poll_detect(1<<0x03); s68k_poll_detect(1<<0x03);
return scd.regs[0x03>>1].w; return scd.regs[0x03>>1].w;
} }
/* CDC host data (word access only ?) */ /* CDC host data (word access only ?) */
if (address == 0xff8008) if (address == 0x08)
{ {
return cdc_host_r(); return cdc_host_r();
} }
/* LED & RESET status */ /* LED & RESET status */
if (address == 0xff8000) if (address == 0x00)
{ {
/* register $00 is reserved for MAIN-CPU, we use $06 instead */ /* register $00 is reserved for MAIN-CPU, we use $06 instead */
return scd.regs[0x06>>1].w; return scd.regs[0x06>>1].w;
} }
/* Stopwatch counter (word access only ?) */ /* Stopwatch counter (word access only ?) */
if (address == 0xff800c) if (address == 0x0c)
{ {
/* cycle-accurate counter value */ /* cycle-accurate counter value */
return (scd.regs[0x0c>>1].w + ((s68k.cycles - scd.stopwatch) / TIMERS_SCYCLES_RATIO)) & 0xfff; return (scd.regs[0x0c>>1].w + ((s68k.cycles - scd.stopwatch) / TIMERS_SCYCLES_RATIO)) & 0xfff;
} }
/* Font data */ /* Font data */
if ((address >= 0xff8050) && (address <= 0xff8056)) if ((address >= 0x50) && (address <= 0x56))
{ {
/* shifted 4-bit input (xxxx00) */ /* shifted 4-bit input (xxxx00) */
uint8 bits = (scd.regs[0x4e>>1].w >> (((address & 6) ^ 6) << 1)) << 2; uint8 bits = (scd.regs[0x4e>>1].w >> (((address & 6) ^ 6) << 1)) << 2;
@ -671,14 +677,14 @@ static unsigned int scd_read_word(unsigned int address)
} }
/* Subcode buffer */ /* Subcode buffer */
else if (address >= 0xff8100) else if (address & 0x100)
{ {
/* 64 x 16-bit mirrored */ /* 64 x 16-bit mirrored */
address &= 0x17f; address &= 0x17f;
} }
/* default registers */ /* default registers */
return scd.regs[(address >> 1) & 0xff].w; return scd.regs[address >> 1].w;
} }
INLINE void word_ram_switch(uint8 mode) INLINE void word_ram_switch(uint8 mode)
@ -745,8 +751,8 @@ INLINE void word_ram_switch(uint8 mode)
static void scd_write_byte(unsigned int address, unsigned int data) static void scd_write_byte(unsigned int address, unsigned int data)
{ {
/* PCM area (8K) is mirrored into $FF0000-$FF7FFF */ /* PCM area (8K) mirrored into $xF0000-$xF7FFF */
if (address < 0xff8000) if (!(address & 0x8000))
{ {
/* get /LDS only */ /* get /LDS only */
if (address & 1) if (address & 1)
@ -1026,8 +1032,8 @@ static void scd_write_byte(unsigned int address, unsigned int data)
static void scd_write_word(unsigned int address, unsigned int data) static void scd_write_word(unsigned int address, unsigned int data)
{ {
/* PCM area (8K) is mirrored into $FF0000-$FF7FFF */ /* PCM area (8K) mirrored into $xF0000-$xF7FFF */
if (address < 0xff8000) if (!(address & 0x8000))
{ {
/* get /LDS only */ /* get /LDS only */
pcm_write((address >> 1) & 0x1fff, data); pcm_write((address >> 1) & 0x1fff, data);