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Merge git://github.com/ekeeke/Genesis-Plus-GX

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This commit is contained in:
twinaphex 2013-02-02 17:47:50 +01:00
commit 5d03f645ea
6 changed files with 53 additions and 24 deletions
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6
source/cd_hw/scd.c
View File

@ -92,6 +92,12 @@ void prg_ram_dma_w(unsigned int words)
/* update DMA source address */
cdc.dac.w += (words << 1);
/* check PRG-RAM write protected area */
if (dst_index < (scd.regs[0x02>>1].byte.h << 9))
{
return;
}
/* DMA transfer */
while (words--)
{

25
source/genesis.c
View File

@ -327,8 +327,33 @@ void gen_reset(int hard_reset)
/* reset Z80 */
z80_reset();
/* some Z80 registers need to be initialized on Power ON */
if (hard_reset)
{
/* Power Base Converter specific */
if (system_hw == SYSTEM_PBC)
{
/* startup code logic (verified on real hardware): */
/* 21 01 E1 : LD HL, $E101
25 -- -- : DEC H
F9 -- -- : LD SP,HL
C7 -- -- : RST $00
01 01 -- : LD BC, $xx01
*/
Z80.hl.w.l = 0xE001;
Z80.sp.w.l = 0xDFFF;
Z80.r = 4;
}
/* Master System specific (when BIOS is disabled) */
else if ((system_hw & SYSTEM_SMS) && (!(config.bios & 1) || !(system_bios & SYSTEM_SMS)))
{
/* usually done by BIOS & required by some SMS games that don't initialize SP */
Z80.sp.w.l = 0xDFFF;
}
}
}
/*-----------------------------------------------------------------------*/
/* OS ROM / TMSS register control functions (Genesis mode) */

16
source/m68k/m68kcpu.h
View File

@ -1070,28 +1070,36 @@ INLINE uint OPER_PCIX_32(void) {uint ea = EA_PCIX_32(); return m68ki_read_pcre
/* ---------------------------- Stack Functions --------------------------- */
/* Push/pull data from the stack */
/* Optimized access assuming stack is always located in ROM/RAM [EkeEke] */
INLINE void m68ki_push_16(uint value)
{
REG_SP = MASK_OUT_ABOVE_32(REG_SP - 2);
m68ki_write_16(REG_SP, value);
/*m68ki_write_16(REG_SP, value);*/
*(uint16 *)(m68ki_cpu.memory_map[(REG_SP>>16)&0xff].base + (REG_SP & 0xffff)) = value;
}
INLINE void m68ki_push_32(uint value)
{
REG_SP = MASK_OUT_ABOVE_32(REG_SP - 4);
m68ki_write_32(REG_SP, value);
/*m68ki_write_32(REG_SP, value);*/
*(uint16 *)(m68ki_cpu.memory_map[(REG_SP>>16)&0xff].base + (REG_SP & 0xffff)) = value >> 16;
*(uint16 *)(m68ki_cpu.memory_map[((REG_SP + 2)>>16)&0xff].base + ((REG_SP + 2) & 0xffff)) = value & 0xffff;
}
INLINE uint m68ki_pull_16(void)
{
uint sp = REG_SP;
REG_SP = MASK_OUT_ABOVE_32(REG_SP + 2);
return m68ki_read_16(REG_SP-2);
return m68k_read_immediate_16(sp);
/*return m68ki_read_16(sp);*/
}
INLINE uint m68ki_pull_32(void)
{
uint sp = REG_SP;
REG_SP = MASK_OUT_ABOVE_32(REG_SP + 4);
return m68ki_read_32(REG_SP-4);
return m68k_read_immediate_32(sp);
/*return m68ki_read_32(sp);*/
}

6
source/mem68k.c
View File

@ -650,6 +650,12 @@ void ctrl_io_write_byte(unsigned int address, unsigned int data)
return;
}
case 0x02: /* PRG-RAM Write Protection */
{
scd.regs[0x02>>1].byte.h = data;
return;
}
case 0x03: /* Memory mode */
{
m68k_poll_sync(0x02);

21
source/z80/z80.c
View File

@ -31,6 +31,7 @@
* This Z80 emulator assumes a ZiLOG NMOS model.
*
* Additional changes [Eke-Eke]:
* - Removed z80_burn function (unused)
* - Discarded multi-chip support (unused)
* - Fixed cycle counting for FD and DD prefixed instructions
* - Fixed behavior of chained FD and DD prefixes (R register should be only incremented by one
@ -3358,11 +3359,9 @@ void z80_init(const void *config, int (*irqcallback)(int))
Z80.daisy = config;
Z80.irq_callback = irqcallback;
/* Reset registers to their initial values (NB: should be random on real hardware) */
AF = BC = DE = HL = 0;
/* Clear registers values (NB: should be random on real hardware ?) */
AF = BC = DE = HL = SP = IX = IY =0;
F = ZF; /* Zero flag is set */
IX = IY = 0xffff; /* IX and IY are FFFF after a reset! (from MAME) */
SP = 0xdfff; /* required by some SMS games that don't initialize SP */
/* setup cycle tables */
cc[Z80_TABLE_op] = cc_op;
@ -3411,20 +3410,6 @@ void z80_run(unsigned int cycles)
}
}
/****************************************************************************
* Burn 'cycles' T-states. Adjust R register for the lost time
****************************************************************************/
void z80_burn(unsigned int cycles)
{
if( cycles > 0 )
{
/* NOP takes 4 cycles per instruction */
int n = (cycles + 3) / 4;
R += n;
Z80.cycles += 4 * n * 15;
}
}
/****************************************************************************
* Get all registers in given buffer
****************************************************************************/

1
source/z80/z80.h
View File

@ -62,7 +62,6 @@ extern unsigned char (*z80_readport)(unsigned int port);
extern void z80_init(const void *config, int (*irqcallback)(int));
extern void z80_reset (void);
extern void z80_run(unsigned int cycles);
extern void z80_burn(unsigned int cycles);
extern void z80_get_context (void *dst);
extern void z80_set_context (void *src);
extern void z80_set_irq_line(unsigned int state);