mirror of
https://github.com/ekeeke/Genesis-Plus-GX.git
synced 2024-09-10 16:53:15 +02:00
Merge git://github.com/ekeeke/Genesis-Plus-GX
This commit is contained in:
commit
5d03f645ea
@ -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--)
|
||||
{
|
||||
|
@ -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) */
|
||||
|
@ -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);*/
|
||||
}
|
||||
|
||||
|
||||
|
@ -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);
|
||||
|
@ -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
|
||||
****************************************************************************/
|
||||
|
@ -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);
|
||||
|
Loading…
Reference in New Issue
Block a user