notes

midisynth/dds_01/dds_01.ino

@@ -1,5 +1,5 @@
 
-
+ //dds01 
 
 #include "avr/pgmspace.h"
 
@@ -76,13 +76,12 @@ void TC5_Handler()                                         // Interrupt Service
     // read value fron ROM sine table and send to PWM DAC
 
     uint32_t value = pgm_read_byte_near(sine256 + icnt);
-
-    // value = value << 1;
-
+
 
     analogWrite(A0, value);
 
 
+    // toggle a bit too...just to measure things.
     counter++;
     if (counter % 2 == 0) {
       digitalWrite(A2, true);

midisynth/dds_01/readme.md

@@ -0,0 +1,17 @@
+# DDS 01  
+
+Simple tones
+
+We are going to work our way to something that works incrementally.
+Mostly, because this is how I learn and I find that if I have to go back to relearn things....its just easier that way.
+
+Start out with a simple sketch that works with TWO timers.  T4 and T5.
+
+One is going pretty fast, and is our DDS ( Direct Digital Synthesis) timer.
+Its a 32 bit counter that you shift by 24 bits and use the last 8 bits as an index into your wave table.
+
+The other timer does nothing.
+
+If successful, you should be hearing a tone on the dac pin and a squarewave
+on the other outside of audio, but enough to verify the timing of the interrupt.
+

midisynth/dds_02/readme.md

@@ -0,0 +1,3 @@
+# dds02
+
+add random notes via the slower timer

midisynth/dds_03/readme.md

@@ -0,0 +1,3 @@
+# dds03
+
+add second note and envelope

midisynth/dds_04/readme.md

@@ -0,0 +1,3 @@
+# dds04
+
+roll back some sound stuff, but add midi