Merge branch 'teensy_dac' of dronus/MicroDexed into master

Many thanks!

MicroDexed.ino

@@ -80,6 +80,16 @@ AudioOutputI2S           i2s1;
 AudioConnection          patchCord11(volume_r, 0, i2s1, 0);
 AudioConnection          patchCord12(volume_l, 0, i2s1, 1);
 AudioControlWM8731master wm8731_1;
+#elif defined(TEENSY_DAC)
+AudioOutputAnalogStereo  dacOut;
+AudioConnection          patchCord11(volume_r, 0, dacOut, 0);
+AudioConnection          patchCord12(volume_l, 0, dacOut, 1);
+#elif defined(TEENSY_DAC_SYMMETRIC)
+AudioOutputAnalogStereo  dacOut;
+AudioMixer4              invMixer;
+AudioConnection          patchCord11(volume_l, 0, dacOut  , 0);
+AudioConnection          patchCord12(volume_l, 0, invMixer, 0);
+AudioConnection          patchCord13(invMixer, 0, dacOut  , 1);
 #else
 AudioOutputPT8211        pt8211_1;
 AudioConnection          patchCord11(volume_r, 0, pt8211_1, 0);
@@ -190,6 +200,11 @@ void setup()
   wm8731_1.enable();
   wm8731_1.volume(1.0);
   Serial.println(F("TGA board enabled."));
+#elif defined(TEENSY_DAC)
+  Serial.println(F("Internal DAC enabled."));
+#elif defined(TEENSY_DAC_SYMMETRIC)
+  invMixer.gain(0,-1.f);
+  Serial.println(F("Internal DAC using symmetric outputs enabled."));
 #else
   Serial.println(F("PT8211 enabled."));
 #endif

config.h

@@ -51,9 +51,11 @@
 #define MIDI_DEVICE_NUMBER 0
 
 // AUDIO
-// If nothing is defined PT8211 is used as audio output device!
+// If nothing is defined Teensy internal DAC is used as audio output device!
-#define TEENSY_AUDIO_BOARD 1
+// Left and right channel audio signal is presented on pins A21 and A22.
-//#define TGA_AUDIO_BOARD
+#define TEENSY_DAC
+// #define TEENSY_AUDIO_BOARD 1
+// #define TGA_AUDIO_BOARD
 
 //*************************************************************************************************
 //* MIDI SETTINGS