1 files changed, 27 insertions, 16 deletions

diff --git a/apps/codecs/libgme/hes_apu.h b/apps/codecs/libgme/hes_apu.h
index 8f8a525108..0265e6a3ad 100644
--- a/apps/codecs/libgme/hes_apu.h
+++ b/apps/codecs/libgme/hes_apu.h
@@ -5,40 +5,46 @@
 #define HES_APU_H
 
 #include "blargg_common.h"
+#include "blargg_source.h"
 #include "blip_buffer.h"
 
 enum { amp_range = 0x8000 };
-enum { osc_count = 6 };
-enum { start_addr = 0x0800 };
-enum { end_addr   = 0x0809 };
+enum { osc_count = 6 }; // 0 <= chan < osc_count
+
+// Registers are at io_addr to io_addr+io_size-1
+enum { apu_io_addr = 0x0800 };
+enum { apu_io_size = 10 };
 
 struct Hes_Osc
 {
-        unsigned char wave [32];
+        byte wave [32];
+        int  delay;
+        int  period;
+        int  phase;
+        
+        int  noise_delay;
+        byte noise;
+        unsigned lfsr;
+        
+        byte control;
+        byte balance;
+        byte dac;
         short volume [2];
         int last_amp [2];
-        int delay;
-        int period;
-        unsigned char noise;
-        unsigned char phase;
-        unsigned char balance;
-        unsigned char dac;
-        blip_time_t last_time;
         
-        struct Blip_Buffer* outputs [2];
-        struct Blip_Buffer* chans [3];
-        unsigned noise_lfsr;
-        unsigned char control;
+        blip_time_t last_time;
+        struct Blip_Buffer* output [2];
+        struct Blip_Buffer* outputs [3];
 };
 
 void Osc_run_until( struct Hes_Osc* this, struct Blip_Synth* synth, blip_time_t );
 
 struct Hes_Apu {
-        struct Hes_Osc oscs [osc_count];
         
         int latch;
         int balance;
         struct Blip_Synth synth;
+        struct Hes_Osc oscs [osc_count];
 };
 
 // Init HES apu sound chip
@@ -48,7 +54,12 @@ void Apu_init( struct Hes_Apu* this );
 void Apu_reset( struct Hes_Apu* this );
 
 void Apu_osc_output( struct Hes_Apu* this, int index, struct Blip_Buffer* center, struct Blip_Buffer* left, struct Blip_Buffer* right );
+
+// Emulates to time t, then writes data to addr
 void Apu_write_data( struct Hes_Apu* this, blip_time_t, int addr, int data );
+
+// Emulates to time t, then subtracts t from the current time.
+// OK if previous write call had time slightly after t.
 void Apu_end_frame( struct Hes_Apu* this, blip_time_t );
 
 static inline void Apu_volume( struct Hes_Apu* this, int v ) { Synth_volume( &this->synth, (v*9)/5 / osc_count / amp_range ); }