AudioApplets: Display CPU and MEM

software/src/AudioAppletSubapp.h

@@ -101,14 +101,17 @@ class AudioAppletSubapp {
     for (size_t i = 0; i < Slots; i++) {
       print_applet_line(i);
     }
+
     if (edit_state == EDIT_LEFT) {
       HemisphereAudioApplet& applet = IsStereo(left_cursor)
         ? get_stereo_applet(left_cursor)
         : get_mono_applet(LEFT_HEMISPHERE, left_cursor);
       applet.BaseView();
       gfxFrame(64, 0, 64, 64);
     } else {
-      gfxPrint(65, 2, "R Channel");
+      // gfxPrint(65, 2, "R Channel");
+      gfxPos(65, 2);
+      graphics.printf("MEM%3d%%) R", mem_percent);
       gfxDottedLine(64, 10, 126, 10);
     }
     if (edit_state == EDIT_RIGHT) {
@@ -118,9 +121,23 @@ class AudioAppletSubapp {
       applet.BaseView();
       gfxFrame(0, 0, 64, 64);
     } else {
-      gfxPrint(1, 2, "L Channel");
+      // gfxPrint(1, 2, "L Channel");
+      gfxPos(1, 2);
+      graphics.printf("L (CPU%3d%%", cpu_percent);
       gfxDottedLine(0, 10, 62, 10);
     }
+
+    // Recall that unsigned substraction rolls over correclty, so when millis()
+    // rolls over, this will still work.
+    if (millis() - last_stats_update > 250) {
+      last_stats_update = millis();
+      mem_percent = static_cast<int16_t>(
+        100 * static_cast<float>(AudioMemoryUsageMax()) / OC::AudioIO::AUDIO_MEMORY
+      );
+      cpu_percent = static_cast<int16_t>(AudioProcessorUsageMax());
+      AudioProcessorUsageMaxReset();
+      AudioMemoryUsageMaxReset();
+    }
   }
 
   void HandleEncoderButtonEvent(const UI::Event& event) {
@@ -320,6 +337,10 @@ class AudioAppletSubapp {
 
   uint32_t last_update = 0;
 
+  int16_t mem_percent = 0;
+  int16_t cpu_percent = 0;
+  uint32_t last_stats_update = 0;
+
   enum EditState {
     EDIT_NONE,
     EDIT_LEFT,

software/src/AudioIO.cpp

@@ -19,7 +19,7 @@ namespace OC {
     }
 
     void Init() {
-      AudioMemory(128);
+      AudioMemory(AUDIO_MEMORY);
     }
   }
 }

software/src/AudioIO.h

@@ -4,6 +4,7 @@
 
 namespace OC {
   namespace AudioIO {
+    const int AUDIO_MEMORY = 128;
     AudioInputI2S2& InputStream();
     AudioOutputI2S2& OutputStream();
     void Init();