X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=Pico%2Fcd%2Fpcm.c;h=7bd8685fa8a3573e5fdf41bf23a40e263156b038;hb=bdec53c90b6e53990fc206cabaec31b844f34d1e;hp=1de04d623cdb8c3bf68f43a5474a3e81c94172e1;hpb=abe0ea43b561e2def84cf921b1d6d8c82819ea69;p=picodrive.git

diff --git a/Pico/cd/pcm.c b/Pico/cd/pcm.c
index 1de04d6..7bd8685 100644
--- a/Pico/cd/pcm.c
+++ b/Pico/cd/pcm.c
@@ -1,9 +1,13 @@
+// Emulation routines for the RF5C164 PCM chip.
+// Based on Gens code by Stéphane Dallongeville
+// (c) Copyright 2007, Grazvydas "notaz" Ignotas
+
 #include "../PicoInt.h"
 #include "pcm.h"
 
 static unsigned int g_rate = 0; // 18.14 fixed point
 
-void pcm_write(unsigned int a, unsigned int d)
+PICO_INTERNAL_ASM void pcm_write(unsigned int a, unsigned int d)
 {
 //printf("pcm_write(%i, %02x)\n", a, d);
 
@@ -46,18 +50,17 @@ void pcm_write(unsigned int a, unsigned int d)
 }
 
 
-void pcm_set_rate(int rate)
+PICO_INTERNAL void pcm_set_rate(int rate)
 {
-	double step = 31.8 * 1024.0 / (double) rate; // max <4 @ 8000Hz
+	float step = 31.8 * 1024.0 / (float) rate; // max <4 @ 8000Hz
 	step *= 256*256/4;
 	g_rate = (unsigned int) step;
-	printf("g_rate: %08x\n", g_rate);
+	if (step - (float) g_rate >= 0.5) g_rate++;
+	elprintf(EL_STATUS, "g_rate: %f %08x\n", (double)step, g_rate);
 }
 
 
-// TODO: make use of the fact that max_length == 3
-
-void pcm_update(int *buffer, int length, int stereo)
+PICO_INTERNAL void pcm_update(int *buffer, int length, int stereo)
 {
 	struct pcm_chan *ch;
 	unsigned int step, addr;
@@ -82,7 +85,7 @@ void pcm_update(int *buffer, int length, int stereo)
 		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
-//		printf("step=%i, cstep=%i, mul_l=%i, mul_r=%i, ch=%i, addr=%x, en=%02x\n",
+//		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;