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Additional fixes

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This commit is contained in:
ekeeke31 2010-06-20 20:32:14 +00:00
parent fb4663f2e3
commit a2258d0011
2 changed files with 35 additions and 33 deletions
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26
source/genesis.c
View File

@ -282,15 +282,15 @@ void gen_zbusreq_w(unsigned int data, unsigned int cycles)
/* check if Z80 is going to be restarted */
if (zstate == 3)
{
/* resynchronize with 68k */
mcycles_z80 = cycles;
/* resynchronize with 68k */
mcycles_z80 = cycles;
/* disable 68k access to Z80 bus */
_m68k_memory_map *base = &m68k_memory_map[0xa0];
base->read8 = m68k_read_bus_8;
base->read16 = m68k_read_bus_16;
base->write8 = m68k_unused_8_w;
base->write16 = m68k_unused_16_w;
/* disable 68k access to Z80 bus */
_m68k_memory_map *base = &m68k_memory_map[0xa0];
base->read8 = m68k_read_bus_8;
base->read16 = m68k_read_bus_16;
base->write8 = m68k_unused_8_w;
base->write16 = m68k_unused_16_w;
}
/* update Z80 bus status */
@ -306,7 +306,7 @@ void gen_zreset_w(unsigned int data, unsigned int cycles)
if (zstate == 0)
{
/* resynchronize with 68k */
mcycles_z80 = cycles;
mcycles_z80 = cycles;
/* reset Z80 & YM2612 */
z80_reset();
@ -314,7 +314,7 @@ void gen_zreset_w(unsigned int data, unsigned int cycles)
}
/* check if 68k access to Z80 bus is granted */
else if (zstate == 2)
else if (zstate == 2)
{
/* enable 68k access to Z80 bus */
_m68k_memory_map *base = &m68k_memory_map[0xa0];
@ -322,6 +322,10 @@ void gen_zreset_w(unsigned int data, unsigned int cycles)
base->read16 = z80_read_word;
base->write8 = z80_write_byte;
base->write16 = z80_write_word;
/* reset Z80 & YM2612 */
z80_reset();
fm_reset(cycles);
}
/* update Z80 bus status */
@ -334,7 +338,7 @@ void gen_zreset_w(unsigned int data, unsigned int cycles)
{
/* resynchronize with 68k */
z80_run(cycles);
}
}
/* check if 68k had access to Z80 bus */
else if (zstate == 3)

32
source/vdp.c
View File

@ -117,7 +117,7 @@ static uint32 fifo_latency; /* CPU access latency */
CRAM or VSRAM for a 68K > VDP transfer, in which case it is in words.
*/
static const uint32 dma_rates[16] = {
static const uint8 dma_rates[16] = {
8, 83, 9, 102, /* 68K to VRAM (1 word = 2 bytes) */
16, 167, 18, 205, /* 68K to CRAM or VSRAM */
15, 166, 17, 204, /* DMA fill */
@ -140,10 +140,7 @@ static void dma_fill(unsigned int data);
void vdp_init(void)
{
/* PAL/NTSC timings */
if (vdp_pal)
lines_per_frame = 313;
else
lines_per_frame = 262;
lines_per_frame = vdp_pal ? 313: 262;
}
void vdp_reset(void)
@ -268,25 +265,22 @@ void vdp_restore(uint8 *vdp_regs)
void vdp_update_dma()
{
uint32 dma_cycles = 0;
int dma_cycles = 0;
/* update DMA timings */
uint32 index = dma_type;
if ((status & 8) || !(reg[1] & 0x40))
++index;
if (reg[12] & 1)
index+=2;
unsigned int index = dma_type;
if ((status & 8) || !(reg[1] & 0x40)) index++;
if (reg[12] & 1) index += 2;
/* DMA transfer rate (bytes per line) */
uint32 rate = dma_rates[index];
unsigned int rate = dma_rates[index];
/* 68k cycles left */
int32 left_cycles = (mcycles_vdp + MCYCLES_PER_LINE) - mcycles_68k;
if (left_cycles < 0)
left_cycles = 0;
int left_cycles = (mcycles_vdp + MCYCLES_PER_LINE) - mcycles_68k;
if (left_cycles < 0) left_cycles = 0;
/* DMA bytes left */
uint32 dma_bytes = (left_cycles * rate) / MCYCLES_PER_LINE;
int dma_bytes = (left_cycles * rate) / MCYCLES_PER_LINE;
#ifdef LOGVDP
error("[%d(%d)][%d(%d)] DMA type %d (%d access/line)-> %d access (%d remaining) (%x)\n", v_counter, mcycles_68k/MCYCLES_PER_LINE, mcycles_68k, mcycles_68k%MCYCLES_PER_LINE,dma_type/4, rate, dma_length, dma_bytes, m68k_get_reg (NULL, M68K_REG_PC));
@ -344,7 +338,11 @@ void vdp_ctrl_w(unsigned int data)
/* VDP register write */
reg_w((data >> 8) & 0x1F,data & 0xFF);
}
else pending = 1;
else
{
/* Set pending flag */
pending = 1;
}
addr = addr_latch | (data & 0x3FFF);
code = ((code & 0x3C) | ((data >> 14) & 0x03));