Diff: main.cpp

Revision:

2:225f68a31496

Parent:

1:86ac6f8d9713

Child:

3:b72b559aaee0

--- a/main.cpp	Tue Apr 28 08:48:29 2015 +0000
+++ b/main.cpp	Tue Apr 28 22:54:13 2015 +0000
@@ -11,12 +11,53 @@
 #define PI          3.14159265
 #define N_SAMPLES   15000
 #define K           3.0
+#define K2          10.0
 
 Ticker          out;
 short           sample[ N_SAMPLES ];
 float           amp;
 int             count    = 0;
 float           ci  = 1.0;
+float           base_tone;
+
+enum Tone_list {
+    Tone_A      = 0,
+    Tone_Ais,
+    Tone_B,
+    Tone_C,
+    Tone_Cis,
+    Tone_D,
+    Tone_Dis,
+    Tone_E,
+    Tone_Eis,
+    Tone_F,
+    Tone_G,
+    Tone_Gis,
+};
+
+void init( void );
+void out_sample();
+
+int main() {
+    
+    float   ai;
+    
+    init();
+    
+    while(1) {
+        amp = key0 * 2.0;
+        ai  = distanceSensor.rd();
+        
+        ci  = (2.25 - ai * 1.5);
+        
+        if ( (0.95 < ci) && (ci < 1.05) )
+            led = 1;
+        else
+            led = 0;
+            
+        wait( 0.001 );
+    }
+}
 
 void init( void )
 {
@@ -31,32 +72,15 @@
         sample[ i ] = (float)i / (float)N_SAMPLES;
     }
 #endif
+
+    base_tone   = (442.0 * pow( 2.0, (float)Tone_C / 12.0 )) /K2 * K;
+    
+    i2c.frequency(400000);
+    out.attach( &out_sample, 1.0 / ((float)(N_SAMPLES / K) * K2) );
 }
 
 void out_sample()
 {
     ao      = 0.5 + (amp * ((float)sample[ count % N_SAMPLES  ] / 65536.0));
-    count  += (int)(52.3251 * K * ci);
+    count  += (int)(base_tone * ci);
 }
-
-
-int main() {
-    init();
-    i2c.frequency(400000);
-    out.attach( &out_sample, 1.0 / ((float)(N_SAMPLES / K) * 10.0) );
-    float   ai;
-    while(1) {
-        ai  = distanceSensor.rd();
-
-        
-        ci  = (2.25 - ai * 1.5);
-        amp = key0 * 2.0;
-        
-        if ( (0.95 < ci) && (ci < 1.05) )
-            led = 1;
-        else
-            led = 0;
-            
-        wait( 0.001 );
-    }
-}