Add TFT tutorial example

examples/Tutorial/Part_3_03_TFT_Display/Part_3_03_TFT_Display.ino

+// Advanced Microcontroller-based Audio Workshop
+// 
+// Part 3-3: TFT Display
+
+#include <ILI9341_t3.h>
+#include <font_Arial.h> // from ILI9341_t3
+
+
+///////////////////////////////////
+// copy the Design Tool code here
+///////////////////////////////////
+
+
+
+
+
+#define TFT_DC      20
+#define TFT_CS      21
+#define TFT_RST    255  // 255 = unused, connect to 3.3V
+#define TFT_MOSI     7
+#define TFT_SCLK    14
+#define TFT_MISO    12
+ILI9341_t3 tft = ILI9341_t3(TFT_CS, TFT_DC, TFT_RST, TFT_MOSI, TFT_SCLK, TFT_MISO);
+
+
+void setup() {
+  Serial.begin(9600);
+  delay(500);
+  tft.begin();
+  tft.fillScreen(ILI9341_BLACK);
+  tft.setTextColor(ILI9341_YELLOW);
+  tft.setFont(Arial_24);
+  //tft.setTextSize(3);
+  tft.setCursor(40, 8);
+  tft.println("Peak Meter");
+  
+  AudioMemory(10);
+  sgtl5000_1.enable();
+  sgtl5000_1.volume(0.5);
+  SPI.setMOSI(7);
+  SPI.setSCK(14);
+  if (!(SD.begin(10))) {
+    while (1) {
+      Serial.println("Unable to access the SD card");
+      delay(500);
+    }
+  }
+  delay(1000);
+}
+
+elapsedMillis msecs;
+
+void loop() {
+  if (playSdWav1.isPlaying() == false) {
+    Serial.println("Start playing");
+    //playSdWav1.play("SDTEST1.WAV");
+    //playSdWav1.play("SDTEST2.WAV");
+    playSdWav1.play("SDTEST3.WAV");
+    //playSdWav1.play("SDTEST4.WAV");
+    delay(10); // wait for library to parse WAV info
+  }
+  
+  if (msecs > 15) {
+    if (peak1.available() && peak2.available()) {
+      msecs = 0;
+      float leftNumber = peak1.read();
+      float rightNumber = peak2.read();
+      Serial.print(leftNumber);
+      Serial.print(", ");
+      Serial.print(rightNumber);
+      Serial.println();
+
+      // draw the verticle bars
+      int height = leftNumber * 240;
+      tft.fillRect(60, 280 - height, 40, height, ILI9341_GREEN);
+      tft.fillRect(60, 280 - 240, 40, 240 - height, ILI9341_BLACK);
+      height = rightNumber * 240;
+      tft.fillRect(140, 280 - height, 40, height, ILI9341_GREEN);
+      tft.fillRect(140, 280 - 240, 40, 240 - height, ILI9341_BLACK);
+      // a smarter approach would redraw only the changed portion...
+
+      // draw numbers underneath each bar
+      tft.setFont(Arial_14);
+      tft.fillRect(60, 284, 40, 16, ILI9341_BLACK);
+      tft.setCursor(60, 284);
+      tft.print(leftNumber);
+      tft.fillRect(140, 284, 40, 16, ILI9341_BLACK);
+      tft.setCursor(140, 284);
+      tft.print(rightNumber);
+    }
+  }
+}