Added text helper functions (enlarge, bg color, etc.)

Adafruit_RA8875.cpp

@@ -291,6 +291,31 @@ void Adafruit_RA8875::textTransparent(uint16_t foreColor)
   writeData(temp);  
 }
 
+/**************************************************************************/
+/*!
+      Sets the text enlarge settings, using one of the following values:
+      
+      0 = 1x zoom
+      1 = 2x zoom
+      2 = 3x zoom
+      3 = 4x zoom
+      
+      @args scale[in]   The zoom factor (0..3 for 1-4x zoom)
+*/
+/**************************************************************************/
+void Adafruit_RA8875::textEnlarge(uint8_t scale)
+{
+  if (scale > 3) scale = 3;
+
+  /* Set font size flags */
+  writeCommand(0x22);
+  uint8_t temp = readData();
+  temp &= ~(0xF); // Clears bits 0..3
+  temp |= scale << 2;
+  temp |= scale;
+  writeData(temp);  
+}
+
 /**************************************************************************/
 /*!
       Renders some text on the screen when in text mode

Adafruit_RA8875.h

@@ -64,6 +64,7 @@ class Adafruit_RA8875 : public Adafruit_GFX {
   void    textMode(void);
   void    textColor(uint16_t foreColor, uint16_t bgColor);
   void    textTransparent(uint16_t foreColor);
+  void    textEnlarge(uint8_t scale);
   void    textWrite(uint8_t* buffer, uint16_t len);
   
   void    pushPixels(uint32_t num, uint16_t p);

examples/textmode/textmode.ino

@@ -27,9 +27,18 @@ void setup()
   tft.fillScreen(RA8875_BLACK);
   
   tft.textMode();
+  // tft.textEnlarge(0);
+  // tft.textColor(RA8875_WHITE, RA8875_RED);
   tft.textTransparent(RA8875_WHITE);
-  uint8_t string[14] = "Hello, World!";
+  uint8_t string[15] = "Hello, World! ";
-  tft.textWrite(string, 14);
+  tft.textWrite(string, 15);
+  tft.textWrite(string, 15);
+  tft.textWrite(string, 15);
+  tft.textWrite(string, 15);
+  tft.textWrite(string, 15);
+  tft.textWrite(string, 15);
+  tft.textWrite(string, 15);
+  tft.textWrite(string, 15);
 }
 
 void loop()