Scrolling Text Matrix with Bluetooth app control

1#include <Adafruit_GFX.h>
2#include <Adafruit_NeoMatrix.h>
3#include  <Adafruit_NeoPixel.h>
4#include <BluetoothSerial.h> // Available here : https://github.com/espressif/arduino-esp32/tree/master/libraries/BluetoothSerial
5
6BluetoothSerial  BT_Text;
7
8#define PIN 25 // This is the led signal pin
9
10Adafruit_NeoMatrix  matrix = Adafruit_NeoMatrix(32, 8, PIN,
11  NEO_MATRIX_TOP    + NEO_MATRIX_LEFT  +
12  NEO_MATRIX_COLUMNS + NEO_MATRIX_ZIGZAG,
13  NEO_GRB            + NEO_KHZ800);
14
15int  i; 
16String Text;
17int x = matrix.width();
18int Size;
19
20const uint16_t  colors[] = {
21  matrix.Color(204, 0, 204), matrix.Color(204, 204, 0), matrix.Color(0,  255, 255),
22  matrix.Color(255, 10, 127), matrix.Color(127, 0, 255), matrix.Color(0,  255, 0),
23  matrix.Color(255, 99, 255), matrix.Color(204,177,0), matrix.Color(0,0,244)  };  // Colour presets
24
25void PrintOut() {
26  while (!BT_Text.available())  {
27    }
28    while (BT_Text.available()) {
29      i = BT_Text.read();
30      Text = Text + char (i);
31    }
32}
33
34
35  
36
37void setup() {
38  // Serial.begin(115200);
39  BT_Text.begin("BT_Text");  //Name of the Bluetooth  interface (On your phone)
40  matrix.begin();
41  matrix.setTextWrap(false);
42  matrix.setBrightness(40);
43  matrix.setTextColor(colors[0]);
44  Text = "*MERRY  CHRISTMAS*";
45  Size = Text.length()*6;
46}
47
48
49
50void loop() {
51  if (BT_Text.available()) {
52    i = BT_Text.read();
53      if (i < 9) {
54      matrix.setTextColor(colors[i]);
55      }
56      else {
57        Text  = "";
58        PrintOut();
59        Size = Text.length()*6;
60      }
61      }
62  matrix.fillScreen(0);    //Turn off all the LEDs
63  matrix.setCursor(x,  0);
64  matrix.print(Text);
65  if ( --x < -Size) {
66    x = matrix.width();
67  }
68  matrix.show();
69  delay(50);
70}
71