fixed YM2612 reset on "soft reset"

small optimizations & fixes in FIR resampler code

source/genesis.c

@@ -146,6 +146,7 @@ void gen_reset(uint32 hard_reset)
   /* Reset CPUs */
   resetline = -1;
   gen_running = 1; 
+  fm_reset(0);
   m68k_pulse_reset();
   z80_reset();
 }
@@ -214,8 +215,8 @@ void gen_reset_w(uint32 state)
     }
 
     /* Reset Z80 & YM2612 */
+    fm_reset(mcycles_68k);
     z80_reset();
-    fm_reset();
 
     /* update Z80 bus status */
     zstate &= 2;

source/sound/Fir_Resampler.c

@@ -53,7 +53,7 @@ static void gen_sinc(double rolloff, int width, double offset, double spacing, d
   }
 }
 
-static int available( long input_count )
+/*static int available( long input_count )
 {
   int cycle_count = input_count / input_per_cycle;
   int output_count = cycle_count * res * STEREO;
@@ -74,6 +74,36 @@ static int available( long input_count )
   }
   return output_count;
 }
+*/
+int Fir_Resampler_avail()
+{
+  long count = 0;
+  sample_t* in = buffer;
+  sample_t* end_pos = write_pos;
+  unsigned long skip = skip_bits >> imp_phase;
+  int remain = res - imp_phase;
+  if ( end_pos - in >= WIDTH * STEREO )
+  {
+    end_pos -= WIDTH * STEREO;
+    do
+    {
+			count++;
+      remain--;
+      in += (skip * STEREO) & STEREO;
+      skip >>= 1;
+      in += step;
+
+      if ( !remain )
+      {
+        skip = skip_bits;
+        remain = res;
+      }
+    }
+    while ( in <= end_pos );
+  }
+
+  return count;
+}
 
 int Fir_Resampler_initialize( int new_size )
 {
@@ -191,10 +221,10 @@ int Fir_Resampler_written( void )
 }
 
 /* Number of output samples available */
-int Fir_Resampler_avail( void )
+/*int Fir_Resampler_avail( void )
 {
   return available( write_pos - &buffer [WIDTH * STEREO] );
-}
+}*/
 
 void Fir_Resampler_write( long count )
 {
@@ -274,13 +304,14 @@ int Fir_Resampler_read( sample_t* out, long count )
   return out - out_;
 }
 
+ /* fixed (Eke_Eke) */
 int Fir_Resampler_input_needed( long output_count )
 {
   long input_count = 0;
 
   unsigned long skip = skip_bits >> imp_phase;
   int remain = res - imp_phase;
-  while ( (output_count) > 0 ) /* fixed (Eke_Eke) */
+  while ( (output_count) > 0 )
   {
     input_count += step + (skip & 1) * STEREO;
     skip >>= 1;
@@ -289,13 +320,13 @@ int Fir_Resampler_input_needed( long output_count )
       skip = skip_bits;
       remain = res;
     }
-    output_count -= 2;
+    output_count --;
   }
 
   long input_extra = input_count - (write_pos - &buffer [WRITE_OFFSET]);
   if ( input_extra < 0 )
     input_extra = 0;
-  return input_extra;
+  return (input_extra >> 1);
 }
 
 int Fir_Resampler_skip_input( long count )

source/sound/sound.c

@@ -148,7 +148,7 @@ void sound_init(void)
     Fir_Resampler_time_ratio(mclk / (double)snd.sample_rate / (144.0 * 7.0));
   }
 
-#ifdef LOG_SOUND
+#ifdef LOGSOUND
   error("%d mcycles per PSG samples\n", psg_cycles_ratio);
   error("%d mcycles per FM samples\n", fm_cycles_ratio);
 #endif
@@ -172,26 +172,26 @@ int sound_update(unsigned int cycles)
   /* number of available samples */
   int size = snd.psg.pos - snd.psg.buffer;
 
-#ifdef LOG_SOUND
-  error("%d PSG samples available\n",snd.psg.pos - snd.psg.buffer);
+#ifdef LOGSOUND
+    error("%d PSG samples available\n",size);
 #endif
 
   /* FM resampling */
   if (config.hq_fm)
   {
-    /* resynchronize FM & PSG chips */
-    int remain = Fir_Resampler_input_needed(size << 1) >> 1;
-
     /* get remaining FM samples */
+    int remain = Fir_Resampler_input_needed(size);
+
     if (remain > 0)
     {
+      /* resynchronize FM & PSG chips */
       YM2612Update(Fir_Resampler_buffer(), remain);
       Fir_Resampler_write(remain << 1);
     }
 
     fm_cycles_count = psg_cycles_count;
 
-#ifdef LOG_SOUND
+#ifdef LOGSOUND
     error("%d FM samples available\n",Fir_Resampler_written() >> 1);
 #endif
   }
@@ -200,12 +200,12 @@ int sound_update(unsigned int cycles)
     /* run FM chip until end of frame */
     fm_update(cycles);
 
-#ifdef LOG_SOUND
+#ifdef LOGSOUND
     error("%d FM samples available\n",(snd.fm.pos - snd.fm.buffer)>>1);
 #endif
   }
 
-#ifdef LOG_SOUND
+#ifdef LOGSOUND
   error("%lu PSG cycles run\n",psg_cycles_count);
   error("%lu FM cycles run \n",fm_cycles_count);
 #endif
@@ -214,7 +214,7 @@ int sound_update(unsigned int cycles)
   psg_cycles_count  -= (cycles << 11);
   fm_cycles_count   -= (cycles << 11);
 
-#ifdef LOG_SOUND
+#ifdef LOGSOUND
   error("%lu PSG cycles left\n",psg_cycles_count);
   error("%lu FM cycles left\n",fm_cycles_count);
 #endif
@@ -222,10 +222,10 @@ int sound_update(unsigned int cycles)
   return size;
 }
 
-/* Reset FM chip during 68k execution */
-void fm_reset(void)
+/* Reset FM chip */
+void fm_reset(unsigned int cycles)
 {
-  fm_update(mcycles_68k);
+  fm_update(cycles);
   YM2612ResetChip();
 }
 

source/sound/sound.h

@@ -28,7 +28,7 @@
 extern void sound_init(void);
 extern void sound_reset(void);
 extern int sound_update(unsigned int cycles);
-extern void fm_reset(void);
+extern void fm_reset(unsigned int cycles);
 extern void fm_write(unsigned int cycles, unsigned int address, unsigned int data);
 extern unsigned int fm_read(unsigned int cycles, unsigned int address);
 extern void psg_write(unsigned int cycles, unsigned int data);

source/system.c

@@ -84,7 +84,7 @@ int audio_update (void)
     /* resample into FM output buffer */
     Fir_Resampler_read(fm,size);
 
-#ifdef LOG_SOUND
+#ifdef LOGSOUND
     error("%d FM samples remaining\n",Fir_Resampler_written() >> 1);
 #endif
   }
@@ -93,7 +93,7 @@ int audio_update (void)
     /* adjust remaining samples in FM output buffer*/
     snd.fm.pos -= (size << 1);
 
-#ifdef LOG_SOUND
+#ifdef LOGSOUND
     error("%d FM samples remaining\n",(snd.fm.pos - snd.fm.buffer)>>1);
 #endif
   }
@@ -101,7 +101,7 @@ int audio_update (void)
   /* adjust remaining samples in PSG output buffer*/
   snd.psg.pos -= size;
 
-#ifdef LOG_SOUND
+#ifdef LOGSOUND
   error("%d PSG samples remaining\n",snd.psg.pos - snd.psg.buffer);
 #endif
 
@@ -155,7 +155,7 @@ int audio_update (void)
   memcpy(snd.fm.buffer, fm, (snd.fm.pos - snd.fm.buffer) << 1);
   memcpy(snd.psg.buffer, psg, (snd.psg.pos - snd.psg.buffer) << 1);
 
-#ifdef LOG_SOUND
+#ifdef LOGSOUND
   error("%d samples returned\n\n",size);
 #endif
 
@@ -398,7 +398,7 @@ int system_frame (int do_skip)
       if (line == vdp_height)
       {
         /* render overscan */
-        if (line < end_line)
+        if (!do_skip && (line < end_line))
           render_line(line, 1);
 
         /* update inputs (doing this here fix Warriors of Eternal Sun) */
@@ -439,7 +439,7 @@ int system_frame (int do_skip)
     else
     {
       /* render overscan */
-      if ((line < end_line) || (line >= start_line))
+      if (!do_skip && ((line < end_line) || (line >= start_line)))
         render_line(line, 1);
 
       /* clear any pending Z80 interrupt */