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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)
{
/* PCM area (8K) is mirrored into $FF0000-$FF7FFF */
if (address < 0xff8000)
/* PCM area (8K) mirrored into $xF0000-$xF7FFF */
if (!(address & 0x8000))
{
/* get /LDS only */
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);
#endif
/* only A1-A8 are used for decoding */
address &= 0x1ff;
/* Memory Mode */
if (address == 0xff8003)
if (address == 0x03)
{
s68k_poll_detect(1<<0x03);
return scd.regs[0x03>>1].byte.l;
}
/* MAIN-CPU communication flags */
if (address == 0xff800e)
if (address == 0x0e)
{
s68k_poll_detect(1<<0x0e);
return scd.regs[0x0e>>1].byte.h;
}
/* CDC transfer status */
if (address == 0xff8004)
if (address == 0x04)
{
s68k_poll_detect(1<<0x04);
return scd.regs[0x04>>1].byte.h;
}
/* GFX operation status */
if (address == 0xff8058)
if (address == 0x58)
{
s68k_poll_detect(1<<0x08);
return scd.regs[0x58>>1].byte.h;
}
/* CDC register data (controlled by BIOS, byte access only ?) */
if (address == 0xff8007)
if (address == 0x07)
{
unsigned int data = cdc_reg_r();
#ifdef LOG_CDC
@ -530,21 +533,21 @@ static unsigned int scd_read_byte(unsigned int address)
}
/* LED status */
if (address == 0xff8000)
if (address == 0x00)
{
/* register $00 is reserved for MAIN-CPU, we use $06 instead */
return scd.regs[0x06>>1].byte.h;
}
/* RESET status */
if (address == 0xff8001)
if (address == 0x01)
{
/* always return 1 */
return 0x01;
}
/* Font data */
if ((address >= 0xff8050) && (address <= 0xff8056))
if ((address >= 0x50) && (address <= 0x56))
{
/* shifted 4-bit input (xxxx00) */
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 */
else if (address >= 0xff8100)
else if (address & 0x100)
{
/* 64 x 16-bit mirrored */
address &= 0x17f;
@ -584,17 +587,17 @@ static unsigned int scd_read_byte(unsigned int address)
if (address & 1)
{
/* register LSB */
return scd.regs[(address >> 1) & 0xff].byte.l;
return scd.regs[address >> 1].byte.l;
}
/* 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)
{
/* PCM area (8K) is mirrored into $FF0000-$FF7FFF */
if (address < 0xff8000)
/* PCM area (8K) mirrored into $xF0000-$xF7FFF */
if (!(address & 0x8000))
{
/* get /LDS only */
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);
#endif
/* only A1-A8 are used for decoding */
address &= 0x1ff;
/* Memory Mode */
if (address == 0xff8002)
if (address == 0x02)
{
s68k_poll_detect(1<<0x03);
return scd.regs[0x03>>1].w;
}
/* CDC host data (word access only ?) */
if (address == 0xff8008)
if (address == 0x08)
{
return cdc_host_r();
}
/* LED & RESET status */
if (address == 0xff8000)
if (address == 0x00)
{
/* register $00 is reserved for MAIN-CPU, we use $06 instead */
return scd.regs[0x06>>1].w;
}
/* Stopwatch counter (word access only ?) */
if (address == 0xff800c)
if (address == 0x0c)
{
/* cycle-accurate counter value */
return (scd.regs[0x0c>>1].w + ((s68k.cycles - scd.stopwatch) / TIMERS_SCYCLES_RATIO)) & 0xfff;
}
/* Font data */
if ((address >= 0xff8050) && (address <= 0xff8056))
if ((address >= 0x50) && (address <= 0x56))
{
/* shifted 4-bit input (xxxx00) */
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 */
else if (address >= 0xff8100)
else if (address & 0x100)
{
/* 64 x 16-bit mirrored */
address &= 0x17f;
}
/* default registers */
return scd.regs[(address >> 1) & 0xff].w;
return scd.regs[address >> 1].w;
}
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)
{
/* PCM area (8K) is mirrored into $FF0000-$FF7FFF */
if (address < 0xff8000)
/* PCM area (8K) mirrored into $xF0000-$xF7FFF */
if (!(address & 0x8000))
{
/* get /LDS only */
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)
{
/* PCM area (8K) is mirrored into $FF0000-$FF7FFF */
if (address < 0xff8000)
/* PCM area (8K) mirrored into $xF0000-$xF7FFF */
if (!(address & 0x8000))
{
/* get /LDS only */
pcm_write((address >> 1) & 0x1fff, data);