lowercasing filenames, part3

[picodrive.git] / pico / cd / pcm.c

diff --git a/pico/cd/pcm.c b/pico/cd/pcm.c
new file mode 100644 (file)
index 0000000..9217d37
--- /dev/null
+++ b/pico/cd/pcm.c
@@ -0,0 +1,133 @@
+// Emulation routines for the RF5C164 PCM chip.
+// Based on Gens code by Stéphane Dallongeville
+// (c) Copyright 2007, Grazvydas "notaz" Ignotas
+
+#include "../pico_int.h"
+#include "pcm.h"
+
+static unsigned int g_rate = 0; // 18.14 fixed point
+
+PICO_INTERNAL_ASM void 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);
+       }
+}
+
+
+PICO_INTERNAL void pcm_set_rate(int rate)
+{
+       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);
+}
+
+
+PICO_INTERNAL void pcm_update(int *buffer, 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;
+       }
+}
+