tested midi example

examples/device/midi/src/main.c

@@ -30,6 +30,12 @@
 #include "bsp/board.h"
 #include "tusb.h"
 
+/* This MIDI example send sequence of note (on/off) repeatedly. To test on PC, you need to install
+ * synth software and midi connection management software. On
+ * - Linux (Ubuntu) : install qsynth, qjackctl. Then connect TinyUSB output port to FLUID Synth input port
+ *
+ */
+
 //--------------------------------------------------------------------+
 // MACRO CONSTANT TYPEDEF PROTYPES
 //--------------------------------------------------------------------+
@@ -48,6 +54,7 @@ enum  {
 static uint32_t blink_interval_ms = BLINK_NOT_MOUNTED;
 
 void led_blinking_task(void);
+void midi_task(void);
 
 /*------------- MAIN -------------*/
 int main(void)
@@ -62,6 +69,8 @@ int main(void)
     tud_task();
 
     led_blinking_task();
+
+    midi_task();
   }
 
   return 0;
@@ -98,6 +107,49 @@ void tud_resume_cb(void)
   blink_interval_ms = BLINK_MOUNTED;
 }
 
+//--------------------------------------------------------------------+
+// MIDI Task
+//--------------------------------------------------------------------+
+
+// Variable that holds the current position in the sequence.
+uint32_t note_pos = 0;
+
+// Store example melody as an array of note values
+uint8_t note_sequence[] =
+{
+  74,78,81,86,90,93,98,102,57,61,66,69,73,78,81,85,88,92,97,100,97,92,88,85,81,78,
+  74,69,66,62,57,62,66,69,74,78,81,86,90,93,97,102,97,93,90,85,81,78,73,68,64,61,
+  56,61,64,68,74,78,81,86,90,93,98,102
+};
+
+void midi_task(void)
+{
+  static uint32_t start_ms = 0;
+
+  // send note every 1000 ms
+  if (board_millis() - start_ms < 286) return; // not enough time
+  start_ms += 286;
+
+  // Previous positions in the note sequence.
+  int previous = note_pos - 1;
+
+  // If we currently are at position 0, set the
+  // previous position to the last note in the sequence.
+  if (previous < 0) previous = sizeof(note_sequence) - 1;
+
+  // Send Note On for current position at full velocity (127) on channel 1.
+  tudi_midi_write24(0, 0x90, note_sequence[note_pos], 127);
+
+  // Send Note Off for previous note.
+  tudi_midi_write24(0, 0x80, note_sequence[previous], 0);
+
+  // Increment position
+  note_pos++;
+
+  // If we are at the end of the sequence, start over.
+  if (note_pos >= sizeof(note_sequence)) note_pos = 0;
+}
+
 //--------------------------------------------------------------------+
 // BLINKING TASK
 //--------------------------------------------------------------------+
@@ -106,7 +158,7 @@ void led_blinking_task(void)
   static uint32_t start_ms = 0;
   static bool led_state = false;
 
-  // Blink every 1000 ms
+  // Blink every interval ms
   if ( board_millis() - start_ms < blink_interval_ms) return; // not enough time
   start_ms += blink_interval_ms;