function to print upside down on a 7 segment display

rotated_display.h

// Function to display rotated characters
// on a 7 segment display to go with TM1637Display
//
// Usage:
//    dispArr(int[0,4]);
//
//        eg:
//        dispArr(104);


// Create an array to send to the display
// from flipped characters
void dispArr(int n) {
  // Make a blank display
  uint8_t Disp[] = {0x00,0x00,0x00,0x00};
  char input [4];
  // Pad with 0s
  sprintf(input, "%04d", n); 
  for (int i = 3; i >= 0; i--) {
    // Make an upside down pattern for each number
    Disp[i] = char2segments(input[3-i]);
  }
  tm1637.setSegments(Disp);
}

// Map of segment patterns to characters
// This one has been rotated 180.
uint8_t char2segments(char c) {
  switch (c) {
      case ' ' : return 0x00;
      case '-' : return 0x40;
      case '0' : return 0x3F;
      case '1' : return 0x30;
      case '2' : return 0x5B;
      case '3' : return 0x79;
      case '4' : return 0x74;
      case '5' : return 0x6D;
      case '6' : return 0x6F;
      case '7' : return 0x38;
      case '8' : return 0x7F;
      case '9' : return 0x7D;
      case 'A' : return 0x7E;
      case 'B' : return 0x7F;
      case 'C' : return 0x0F;
      case 'D' : return 0x3F;
      case 'E' : return 0x4F;
      case 'F' : return 0x4E;
      case 'G' : return 0x6F;
      case 'H' : return 0x76;
      case 'I' : return 0x30;
      case 'J' : return 0x3B;
      case 'K' : return 0x76;
      case 'L' : return 0x07;
      case 'O' : return 0x3F;
      case 'P' : return 0x5E;
      case 'S' : return 0x6D;
      case 'U' : return 0x37;
      case 'V' : return 0x37;
      case 'Y' : return 0x74;
      case 'Z' : return 0x5B;
      case '_' : return 0x01;
      case 'b' : return 0x67;
      case 'c' : return 0x43;
      case 'd' : return 0x73;
      case 'h' : return 0x66;
      case 'l' : return 0x30;
      case 'n' : return 0x62;
      case 'o' : return 0x63;
      case 'r' : return 0x42;
  }
  return 0;
}