1 files changed, 89 insertions, 0 deletions
diff --git a/apps/codecs/libgme/nes_vrc7_apu.c b/apps/codecs/libgme/nes_vrc7_apu.c
new file mode 100644
index 0000000000..d8768bfc7e
--- /dev/null
+++ b/apps/codecs/libgme/nes_vrc7_apu.c
@@ -0,0 +1,89 @@
+#include "nes_vrc7_apu.h"
+#include "blargg_source.h"
+int const period = 36; // NES CPU clocks per FM clock
+void Vrc7_init( struct Nes_Vrc7_Apu* this )
+{
+        Synth_init( &this->synth );
+        
+        OPLL_new ( &this->opll, 3579545, 3579545 / 72 );
+    OPLL_reset_patch( &this->opll, OPLL_VRC7_TONE );
+        
+        this->osc.output = 0;
+        this->osc.last_amp = 0;
+        this->mask = 0;
+        Vrc7_volume( this, 1.0 );
+        Vrc7_reset( this );
+}
+void Vrc7_reset( struct Nes_Vrc7_Apu* this )
+{
+        this->addr      = 0;
+        this->next_time = 0;
+        this->osc.last_amp = 0;
+        OPLL_reset (&this->opll);       
+        OPLL_setMask(&this->opll, this->mask);
+}
+void Vrc7_set_rate( struct Nes_Vrc7_Apu* this, double r )
+{
+        OPLL_set_quality( &this->opll, r < 44100 ? 0 : 1 );
+    OPLL_set_rate( &this->opll, (e_uint32)r );
+}
+void Vrc7_write_reg( struct Nes_Vrc7_Apu* this, int data )
+{
+        this->addr = data;
+}
+void Vrc7_run_until( struct Nes_Vrc7_Apu* this, blip_time_t end_time );
+void Vrc7_write_data( struct Nes_Vrc7_Apu* this, blip_time_t time, int data )
+{       
+        if ( time > this->next_time )
+                Vrc7_run_until( this, time );
+        OPLL_writeIO( &this->opll, 0, this->addr );
+        OPLL_writeIO( &this->opll, 1, data );
+}
+void Vrc7_end_frame( struct Nes_Vrc7_Apu* this, blip_time_t time )
+{
+        if ( time > this->next_time )
+                Vrc7_run_until( this, time );
+        
+        this->next_time -= time;
+        assert( this->next_time >= 0 );
+        
+        if ( this->osc.output )
+                Blip_set_modified( this->osc.output );
+}
+void Vrc7_run_until( struct Nes_Vrc7_Apu* this, blip_time_t end_time )
+{
+        require( end_time > this->next_time );
+        blip_time_t time = this->next_time;
+        OPLL* opll = &this->opll; // cache
+        struct Blip_Buffer* const output = this-> osc.output;
+        if ( output )
+        {
+                do
+                {
+                        int amp = OPLL_calc( opll ) << 1;
+                        int delta = amp - this->osc.last_amp;
+                        if ( delta )
+                        {
+                                this->osc.last_amp = amp;
+                                Synth_offset_inline( &this->synth, time, delta, output );
+                        }
+                        time += period;
+                }
+                while ( time < end_time );
+        }
+        this->next_time = time;
+}

diff --git a/apps/codecs/libgme/nes_vrc7_apu.c b/apps/codecs/libgme/nes_vrc7_apu.c new file mode 100644 index 0000000000..d8768bfc7e --- /dev/null +++ b/apps/codecs/libgme/nes_vrc7_apu.c
@@ -0,0 +1,89 @@
	1
	2	#include "nes_vrc7_apu.h"
	3	#include "blargg_source.h"
	4
	5	int const period = 36; // NES CPU clocks per FM clock
	6
	7	void Vrc7_init( struct Nes_Vrc7_Apu* this )
	8	{
	9	Synth_init( &this->synth );
	10
	11	OPLL_new ( &this->opll, 3579545, 3579545 / 72 );
	12	OPLL_reset_patch( &this->opll, OPLL_VRC7_TONE );
	13
	14	this->osc.output = 0;
	15	this->osc.last_amp = 0;
	16	this->mask = 0;
	17
	18	Vrc7_volume( this, 1.0 );
	19	Vrc7_reset( this );
	20	}
	21
	22	void Vrc7_reset( struct Nes_Vrc7_Apu* this )
	23	{
	24	this->addr = 0;
	25	this->next_time = 0;
	26	this->osc.last_amp = 0;
	27
	28	OPLL_reset (&this->opll);
	29	OPLL_setMask(&this->opll, this->mask);
	30	}
	31
	32	void Vrc7_set_rate( struct Nes_Vrc7_Apu* this, double r )
	33	{
	34	OPLL_set_quality( &this->opll, r < 44100 ? 0 : 1 );
	35	OPLL_set_rate( &this->opll, (e_uint32)r );
	36	}
	37
	38	void Vrc7_write_reg( struct Nes_Vrc7_Apu* this, int data )
	39	{
	40	this->addr = data;
	41	}
	42
	43	void Vrc7_run_until( struct Nes_Vrc7_Apu* this, blip_time_t end_time );
	44	void Vrc7_write_data( struct Nes_Vrc7_Apu* this, blip_time_t time, int data )
	45	{
	46	if ( time > this->next_time )
	47	Vrc7_run_until( this, time );
	48
	49	OPLL_writeIO( &this->opll, 0, this->addr );
	50	OPLL_writeIO( &this->opll, 1, data );
	51	}
	52
	53	void Vrc7_end_frame( struct Nes_Vrc7_Apu* this, blip_time_t time )
	54	{
	55	if ( time > this->next_time )
	56	Vrc7_run_until( this, time );
	57
	58	this->next_time -= time;
	59	assert( this->next_time >= 0 );
	60
	61	if ( this->osc.output )
	62	Blip_set_modified( this->osc.output );
	63	}
	64
	65	void Vrc7_run_until( struct Nes_Vrc7_Apu* this, blip_time_t end_time )
	66	{
	67	require( end_time > this->next_time );
	68
	69	blip_time_t time = this->next_time;
	70	OPLL* opll = &this->opll; // cache
	71	struct Blip_Buffer* const output = this-> osc.output;
	72	if ( output )
	73	{
	74	do
	75	{
	76	int amp = OPLL_calc( opll ) << 1;
	77	int delta = amp - this->osc.last_amp;
	78	if ( delta )
	79	{
	80	this->osc.last_amp = amp;
	81	Synth_offset_inline( &this->synth, time, delta, output );
	82	}
	83	time += period;
	84	}
	85	while ( time < end_time );
	86	}
	87
	88	this->next_time = time;
	89	}