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[N64] Fix audio sync issues in Super Mario 64 and probably others, and also bring PI DMA speed into the realm of reality. [Ryan Holtz]

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[N64] Change PI DMA speed from 3 cycles/word to 5.08 cycles, as average PI speed is between 2.53 and 2.55 cycles/byte. [Ryan Holtz]
This commit is contained in:
Miodrag Milanovic 2012-02-24 08:51:46 +00:00
parent d615871662
commit fe6a725e91
1 changed files with 16 additions and 8 deletions
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24
src/mame/machine/n64.c
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@ -1299,7 +1299,7 @@ void n64_periphs::ai_dma()
ai_status |= 0x40000000; ai_status |= 0x40000000;
// adjust the timer // adjust the timer
period = attotime::from_hz(DACRATE_NTSC) * ((ai_dacrate + 1) * (current->length / 4)); period = attotime::from_hz(DACRATE_NTSC) * ((ai_dacrate + 1) * (current->length / 8));
ai_timer->adjust(period); ai_timer->adjust(period);
} }
@ -1338,8 +1338,8 @@ READ32_MEMBER( n64_periphs::ai_reg_r )
else if (ai_status & 0x40000000) else if (ai_status & 0x40000000)
{ {
double secs_left = (ai_timer->expire() - machine().time()).as_double(); double secs_left = (ai_timer->expire() - machine().time()).as_double();
unsigned int samples_left = secs_left * DACRATE_NTSC / (ai_dacrate + 1); unsigned int samples_left = (UINT32)(secs_left * (double)DACRATE_NTSC / (double)(ai_dacrate + 1));
ret = samples_left * 4; ret = samples_left * 8;
} }
else else
{ {
@ -1562,7 +1562,7 @@ WRITE32_MEMBER( n64_periphs::pi_reg_w )
pi_dma_dir = 0; pi_dma_dir = 0;
pi_status |= 1; pi_status |= 1;
attotime dma_period = attotime::from_hz(93750000) * (int)((float)(pi_rd_len + 1) * 10.2f); attotime dma_period = attotime::from_hz(93750000) * (int)((float)(pi_rd_len + 1) * 5.08f); // Measured as between 2.53 cycles per byte and 2.55 cycles per byte
//printf("want read dma in %d\n", (pi_rd_len + 1)); //printf("want read dma in %d\n", (pi_rd_len + 1));
pi_dma_timer->adjust(dma_period); pi_dma_timer->adjust(dma_period);
//pi_dma_tick(); //pi_dma_tick();
@ -1575,7 +1575,7 @@ WRITE32_MEMBER( n64_periphs::pi_reg_w )
pi_dma_dir = 1; pi_dma_dir = 1;
pi_status |= 1; pi_status |= 1;
attotime dma_period = attotime::from_hz(93750000) * (int)((float)(pi_wr_len + 1) * 10.2f); attotime dma_period = attotime::from_hz(93750000) * (int)((float)(pi_wr_len + 1) * 5.08f); // Measured as between 2.53 cycles per byte and 2.55 cycles per byte
//printf("want write dma in %d\n", (pi_wr_len + 1)); //printf("want write dma in %d\n", (pi_wr_len + 1));
pi_dma_timer->adjust(dma_period); pi_dma_timer->adjust(dma_period);
@ -1717,6 +1717,14 @@ int n64_periphs::pif_channel_handle_command(int channel, int slength, UINT8 *sda
case 0x00: // Read status case 0x00: // Read status
case 0xff: // Reset case 0xff: // Reset
{ {
if(command == 0)
{
//printf("Read status\n");
}
else
{
//printf("Reset\n");
}
switch (channel) switch (channel)
{ {
case 0: case 0:
@ -1801,7 +1809,7 @@ int n64_periphs::pif_channel_handle_command(int channel, int slength, UINT8 *sda
address = (sdata[1] << 8) | (sdata[2]); address = (sdata[1] << 8) | (sdata[2]);
address &= ~0x1f; address &= ~0x1f;
//printf("Read mempak at %04x\n", address); ////printf("Read mempak at %04x\n", address);
if(address == 0x8000) if(address == 0x8000)
{ {
@ -1831,7 +1839,7 @@ int n64_periphs::pif_channel_handle_command(int channel, int slength, UINT8 *sda
UINT32 address = (sdata[1] << 8) | (sdata[2]); UINT32 address = (sdata[1] << 8) | (sdata[2]);
address &= ~0x1f; address &= ~0x1f;
//printf("Write mempak at %04x\n", address); ////printf("Write mempak at %04x\n", address);
if (address >= 0x8000) if (address >= 0x8000)
{ {
@ -2026,7 +2034,7 @@ void n64_periphs::handle_pif()
} }
} }
//pif_ram[0x3f] = 0; pif_ram[0x3f] = 0;
} }
/*printf("After:\n"); fflush(stdout); /*printf("After:\n"); fflush(stdout);