-// Emulation routines for the RF5C164 PCM chip.
-// Based on Gens code by Stéphane Dallongeville
-// (c) Copyright 2007, Grazvydas "notaz" Ignotas
+/*
+ * Emulation routines for the RF5C164 PCM chip
+ * (C) notaz, 2007, 2013
+ *
+ * This work is licensed under the terms of MAME license.
+ * See COPYING file in the top-level directory.
+ */
#include "../pico_int.h"
-#include "pcm.h"
-static unsigned int g_rate = 0; // 18.14 fixed point
+#define PCM_STEP_SHIFT 11
-PICO_INTERNAL_ASM void pcm_write(unsigned int a, unsigned int d)
+void pcd_pcm_write(unsigned int a, unsigned int d)
{
-//printf("pcm_write(%i, %02x)\n", a, d);
-
- if (a < 7)
- {
- Pico_mcd->pcm.ch[Pico_mcd->pcm.cur_ch].regs[a] = d;
- }
- else if (a == 7) // control register
- {
- if (d & 0x40) Pico_mcd->pcm.cur_ch = d & 7;
- else Pico_mcd->pcm.bank = d & 0xf;
- Pico_mcd->pcm.control = d;
- // dprintf("pcm control=%02x", Pico_mcd->pcm.control);
- }
- else if (a == 8) // sound on/off
- {
- if (!(Pico_mcd->pcm.enabled & 0x01)) Pico_mcd->pcm.ch[0].addr =
- Pico_mcd->pcm.ch[0].regs[6] << (PCM_STEP_SHIFT + 8);
- if (!(Pico_mcd->pcm.enabled & 0x02)) Pico_mcd->pcm.ch[1].addr =
- Pico_mcd->pcm.ch[1].regs[6] << (PCM_STEP_SHIFT + 8);
- if (!(Pico_mcd->pcm.enabled & 0x04)) Pico_mcd->pcm.ch[2].addr =
- Pico_mcd->pcm.ch[2].regs[6] << (PCM_STEP_SHIFT + 8);
- if (!(Pico_mcd->pcm.enabled & 0x08)) Pico_mcd->pcm.ch[3].addr =
- Pico_mcd->pcm.ch[3].regs[6] << (PCM_STEP_SHIFT + 8);
- if (!(Pico_mcd->pcm.enabled & 0x10)) Pico_mcd->pcm.ch[4].addr =
- Pico_mcd->pcm.ch[4].regs[6] << (PCM_STEP_SHIFT + 8);
- if (!(Pico_mcd->pcm.enabled & 0x20)) Pico_mcd->pcm.ch[5].addr =
- Pico_mcd->pcm.ch[5].regs[6] << (PCM_STEP_SHIFT + 8);
- if (!(Pico_mcd->pcm.enabled & 0x40)) Pico_mcd->pcm.ch[6].addr =
- Pico_mcd->pcm.ch[6].regs[6] << (PCM_STEP_SHIFT + 8);
- if (!(Pico_mcd->pcm.enabled & 0x80)) Pico_mcd->pcm.ch[7].addr =
- Pico_mcd->pcm.ch[7].regs[6] << (PCM_STEP_SHIFT + 8);
-// printf("addr %x %x %x %x %x %x %x %x\n", Pico_mcd->pcm.ch[0].addr, Pico_mcd->pcm.ch[1].addr
-// , Pico_mcd->pcm.ch[2].addr, Pico_mcd->pcm.ch[3].addr, Pico_mcd->pcm.ch[4].addr, Pico_mcd->pcm.ch[5].addr
-// , Pico_mcd->pcm.ch[6].addr, Pico_mcd->pcm.ch[7].addr);
-
- Pico_mcd->pcm.enabled = ~d;
-//printf("enabled=%02x\n", Pico_mcd->pcm.enabled);
- }
+ unsigned int cycles = SekCyclesDoneS68k();
+ if ((int)(cycles - Pico_mcd->pcm.update_cycles) >= 384)
+ pcd_pcm_sync(cycles);
+
+ if (a < 7)
+ {
+ Pico_mcd->pcm.ch[Pico_mcd->pcm.cur_ch].regs[a] = d;
+ }
+ else if (a == 7) // control register
+ {
+ if (d & 0x40)
+ Pico_mcd->pcm.cur_ch = d & 7;
+ else
+ Pico_mcd->pcm.bank = d & 0xf;
+ Pico_mcd->pcm.control = d;
+ elprintf(EL_CD, "pcm control %02x", Pico_mcd->pcm.control);
+ }
+ else if (a == 8)
+ {
+ Pico_mcd->pcm.enabled = ~d;
+ }
+ Pico_mcd->pcm_regs_dirty = 1;
}
-
-PICO_INTERNAL void pcm_set_rate(int rate)
+unsigned int pcd_pcm_read(unsigned int a)
{
- float step = 31.8 * 1024.0 / (float) rate; // max <4 @ 8000Hz
- step *= 256*256/4;
- g_rate = (unsigned int) step;
- if (step - (float) g_rate >= 0.5) g_rate++;
- elprintf(EL_STATUS, "g_rate: %f %08x\n", (double)step, g_rate);
+ unsigned int d, cycles = SekCyclesDoneS68k();
+ if ((int)(cycles - Pico_mcd->pcm.update_cycles) >= 384)
+ pcd_pcm_sync(cycles);
+
+ d = Pico_mcd->pcm.ch[(a >> 1) & 7].addr >> PCM_STEP_SHIFT;
+ if (a & 1)
+ d >>= 8;
+
+ return d & 0xff;
}
+void pcd_pcm_sync(unsigned int to)
+{
+ unsigned int cycles = Pico_mcd->pcm.update_cycles;
+ int mul_l, mul_r, inc, smp;
+ struct pcm_chan *ch;
+ unsigned int addr;
+ int c, s, steps;
+ int enabled;
+ int *out;
+
+ if ((int)(to - cycles) < 384)
+ return;
+
+ steps = (to - cycles) / 384;
+ if (Pico_mcd->pcm_mixpos + steps > PCM_MIXBUF_LEN)
+ // shouldn't happen, but occasionally does
+ steps = PCM_MIXBUF_LEN - Pico_mcd->pcm_mixpos;
+
+ // PCM disabled or all channels off
+ enabled = Pico_mcd->pcm.enabled;
+ if (!(Pico_mcd->pcm.control & 0x80))
+ enabled = 0;
+ if (!enabled && !Pico_mcd->pcm_regs_dirty)
+ goto end;
+
+ out = Pico_mcd->pcm_mixbuf + Pico_mcd->pcm_mixpos * 2;
+ Pico_mcd->pcm_mixbuf_dirty = 1;
+ Pico_mcd->pcm_regs_dirty = 0;
+
+ for (c = 0; c < 8; c++)
+ {
+ ch = &Pico_mcd->pcm.ch[c];
+
+ if (!(enabled & (1 << c))) {
+ ch->addr = ch->regs[6] << (PCM_STEP_SHIFT + 8);
+ continue; // channel disabled
+ }
+
+ addr = ch->addr;
+ inc = *(unsigned short *)&ch->regs[2];
+ mul_l = ((int)ch->regs[0] * (ch->regs[1] & 0xf)) >> (5+1);
+ mul_r = ((int)ch->regs[0] * (ch->regs[1] >> 4)) >> (5+1);
+
+ for (s = 0; s < steps; s++, addr = (addr + inc) & 0x7FFFFFF)
+ {
+ smp = Pico_mcd->pcm_ram[addr >> PCM_STEP_SHIFT];
+
+ // test for loop signal
+ if (smp == 0xff)
+ {
+ addr = *(unsigned short *)&ch->regs[4]; // loop_addr
+ smp = Pico_mcd->pcm_ram[addr];
+ addr <<= PCM_STEP_SHIFT;
+ if (smp == 0xff)
+ break;
+ }
+
+ if (smp & 0x80)
+ smp = -(smp & 0x7f);
+
+ out[s*2 ] += smp * mul_l; // max 128 * 119 = 15232
+ out[s*2+1] += smp * mul_r;
+ }
+ ch->addr = addr;
+ }
+
+end:
+ Pico_mcd->pcm.update_cycles = cycles + steps * 384;
+ Pico_mcd->pcm_mixpos += steps;
+}
-PICO_INTERNAL void pcm_update(int *buffer, int length, int stereo)
+void pcd_pcm_update(int *buf32, int length, int stereo)
{
- struct pcm_chan *ch;
- unsigned int step, addr;
- int mul_l, mul_r, smp;
- int i, j, k;
- int *out;
-
-
- // PCM disabled or all channels off (to be checked by caller)
- //if (!(Pico_mcd->pcm.control & 0x80) || !Pico_mcd->pcm.enabled) return;
-
-//printf("-- upd %i\n", length);
-
- for (i = 0; i < 8; i++)
- {
- if (!(Pico_mcd->pcm.enabled & (1 << i))) continue; // channel disabled
-
- out = buffer;
- ch = &Pico_mcd->pcm.ch[i];
-
- addr = ch->addr; // >> PCM_STEP_SHIFT;
- mul_l = ((int)ch->regs[0] * (ch->regs[1] & 0xf)) >> (5+1); // (env * pan) >> 5
- mul_r = ((int)ch->regs[0] * (ch->regs[1] >> 4)) >> (5+1);
- step = ((unsigned int)(*(unsigned short *)&ch->regs[2]) * g_rate) >> 14; // freq step
-// fprintf(stderr, "step=%i, cstep=%i, mul_l=%i, mul_r=%i, ch=%i, addr=%x, en=%02x\n",
-// *(unsigned short *)&ch->regs[2], step, mul_l, mul_r, i, addr, Pico_mcd->pcm.enabled);
-
- if (!stereo && mul_l < mul_r) mul_l = mul_r;
-
- for (j = 0; j < length; j++)
- {
-// printf("addr=%08x\n", addr);
- smp = Pico_mcd->pcm_ram[addr >> PCM_STEP_SHIFT];
-
- // test for loop signal
- if (smp == 0xff)
- {
- addr = *(unsigned short *)&ch->regs[4]; // loop_addr
- smp = Pico_mcd->pcm_ram[addr];
- addr <<= PCM_STEP_SHIFT;
- if (smp == 0xff) break;
- }
-
- if (smp & 0x80) smp = -(smp & 0x7f);
-
- *out++ += smp * mul_l; // max 128 * 119 = 15232
- if(stereo)
- *out++ += smp * mul_r;
-
- // update address register
- k = (addr >> PCM_STEP_SHIFT) + 1;
- addr = (addr + step) & 0x7FFFFFF;
-
- for(; k < (addr >> PCM_STEP_SHIFT); k++)
- {
- if (Pico_mcd->pcm_ram[k] == 0xff)
- {
- addr = (unsigned int)(*(unsigned short *)&ch->regs[4]) << PCM_STEP_SHIFT; // loop_addr
- break;
- }
- }
- }
-
- if (Pico_mcd->pcm_ram[addr >> PCM_STEP_SHIFT] == 0xff)
- addr = (unsigned int)(*(unsigned short *)&ch->regs[4]) << PCM_STEP_SHIFT; // loop_addr
-
- ch->addr = addr;
- }
+ int step, *pcm;
+ int p = 0;
+
+ pcd_pcm_sync(SekCyclesDoneS68k());
+
+ if (!Pico_mcd->pcm_mixbuf_dirty || !(PicoIn.opt & POPT_EN_MCD_PCM))
+ goto out;
+
+ step = (Pico_mcd->pcm_mixpos << 16) / length;
+ pcm = Pico_mcd->pcm_mixbuf;
+
+ if (stereo) {
+ while (length-- > 0) {
+ *buf32++ += pcm[0];
+ *buf32++ += pcm[1];
+
+ p += step;
+ pcm += (p >> 16) * 2;
+ p &= 0xffff;
+ }
+ }
+ else {
+ while (length-- > 0) {
+ // mostly unused
+ *buf32++ += pcm[0];
+
+ p += step;
+ pcm += (p >> 16) * 2;
+ p &= 0xffff;
+ }
+ }
+
+ memset(Pico_mcd->pcm_mixbuf, 0,
+ Pico_mcd->pcm_mixpos * 2 * sizeof(Pico_mcd->pcm_mixbuf[0]));
+
+out:
+ Pico_mcd->pcm_mixbuf_dirty = 0;
+ Pico_mcd->pcm_mixpos = 0;
}
+// vim:shiftwidth=2:ts=2:expandtab
notaz.gp2x.de / picodrive.git / blobdiff