diff --git a/OLEDDisplay.cpp b/OLEDDisplay.cpp
index 47ecbece91e3dba4433d5ad573ae472173ce77fa..57566d3cb563339a8266f6d90b99a69d54223146 100644
--- a/OLEDDisplay.cpp
+++ b/OLEDDisplay.cpp
@@ -347,11 +347,11 @@ void OLEDDisplay::drawProgressBar(uint16_t x, uint16_t y, uint16_t width, uint16
   fillCircle(xRadius + maxProgressWidth, yRadius, innerRadius);
 }
 
-void OLEDDisplay::drawFastImage(int16_t xMove, int16_t yMove, int16_t width, int16_t height, const unsigned char *image) {
+void OLEDDisplay::drawFastImage(int16_t xMove, int16_t yMove, int16_t width, int16_t height, const uint8_t *image) {
   drawInternal(xMove, yMove, width, height, image, 0, 0);
 }
 
-void OLEDDisplay::drawXbm(int16_t xMove, int16_t yMove, int16_t width, int16_t height, const unsigned char *xbm) {
+void OLEDDisplay::drawXbm(int16_t xMove, int16_t yMove, int16_t width, int16_t height, const uint8_t *xbm) {
   int16_t widthInXbm = (width + 7) / 8;
   uint8_t data;
 
@@ -525,7 +525,7 @@ void OLEDDisplay::setTextAlignment(OLEDDISPLAY_TEXT_ALIGNMENT textAlignment) {
   this->textAlignment = textAlignment;
 }
 
-void OLEDDisplay::setFont(const unsigned char *fontData) {
+void OLEDDisplay::setFont(const uint8_t *fontData) {
   this->fontData = fontData;
 }
 
@@ -692,7 +692,7 @@ void OLEDDisplay::sendInitCommands(void) {
   sendCommand(DISPLAYON);
 }
 
-void inline OLEDDisplay::drawInternal(int16_t xMove, int16_t yMove, int16_t width, int16_t height, const unsigned char *data, uint16_t offset, uint16_t bytesInData) {
+void inline OLEDDisplay::drawInternal(int16_t xMove, int16_t yMove, int16_t width, int16_t height, const uint8_t *data, uint16_t offset, uint16_t bytesInData) {
   if (width < 0 || height < 0) return;
   if (yMove + height < 0 || yMove > DISPLAY_HEIGHT)  return;
   if (xMove + width  < 0 || xMove > DISPLAY_WIDTH)   return;
diff --git a/OLEDDisplay.h b/OLEDDisplay.h
index b8067fcae7d9f37c64786648d152cc2769846722..c850694859ab886973c2f4c3dfe6ce8694d8217c 100644
--- a/OLEDDisplay.h
+++ b/OLEDDisplay.h
@@ -155,10 +155,10 @@ class OLEDDisplay : public Print {
     void drawProgressBar(uint16_t x, uint16_t y, uint16_t width, uint16_t height, uint8_t progress);
 
     // Draw a bitmap in the internal image format
-    void drawFastImage(int16_t x, int16_t y, int16_t width, int16_t height, const unsigned char *image);
+    void drawFastImage(int16_t x, int16_t y, int16_t width, int16_t height, const uint8_t *image);
 
     // Draw a XBM
-    void drawXbm(int16_t x, int16_t y, int16_t width, int16_t height, const unsigned char *xbm);
+    void drawXbm(int16_t x, int16_t y, int16_t width, int16_t height, const uint8_t *xbm);
 
     /* Text functions */
 
@@ -184,7 +184,7 @@ class OLEDDisplay : public Print {
 
     // Sets the current font. Available default fonts
     // ArialMT_Plain_10, ArialMT_Plain_16, ArialMT_Plain_24
-    void setFont(const unsigned char *fontData);
+    void setFont(const uint8_t *fontData);
 
     /* Display functions */
 
@@ -237,7 +237,7 @@ class OLEDDisplay : public Print {
     OLEDDISPLAY_TEXT_ALIGNMENT   textAlignment = TEXT_ALIGN_LEFT;
     OLEDDISPLAY_COLOR            color         = WHITE;
 
-    const unsigned char          *fontData     = ArialMT_Plain_10;
+    const uint8_t          *fontData     = ArialMT_Plain_10;
 
     // State values for logBuffer
     uint16_t   logBufferSize                   = 0;
@@ -259,7 +259,7 @@ class OLEDDisplay : public Print {
     static char* utf8ascii(String s);
     static byte utf8ascii(byte ascii);
 
-    void inline drawInternal(int16_t xMove, int16_t yMove, int16_t width, int16_t height, const unsigned char *data, uint16_t offset, uint16_t bytesInData) __attribute__((always_inline));
+    void inline drawInternal(int16_t xMove, int16_t yMove, int16_t width, int16_t height, const uint8_t *data, uint16_t offset, uint16_t bytesInData) __attribute__((always_inline));
 
     void drawStringInternal(int16_t xMove, int16_t yMove, char* text, uint16_t textLength, uint16_t textWidth);
 
diff --git a/OLEDDisplayFonts.h b/OLEDDisplayFonts.h
index e885a7036f3379b7603742b41a8dd2055e976456..3544edb80d1721237febea01c3f6389ee6e2ad60 100644
--- a/OLEDDisplayFonts.h
+++ b/OLEDDisplayFonts.h
@@ -1,7 +1,7 @@
 #ifndef OLEDDISPLAYFONTS_h
 #define OLEDDISPLAYFONTS_h
 
-const unsigned char ArialMT_Plain_10[] PROGMEM = {
+const uint8_t ArialMT_Plain_10[] PROGMEM = {
   0x0A, // Width: 10
   0x0D, // Height: 13
   0x20, // First Char: 32
@@ -425,7 +425,7 @@ const unsigned char ArialMT_Plain_10[] PROGMEM = {
   0x20,0x00,0xC8,0x09,0x00,0x06,0xC8,0x01,0x20  // 255
 };
 
-const unsigned char ArialMT_Plain_16[] PROGMEM = {
+const uint8_t ArialMT_Plain_16[] PROGMEM = {
   0x10, // Width: 16
   0x13, // Height: 19
   0x20, // First Char: 32
@@ -848,7 +848,7 @@ const unsigned char ArialMT_Plain_16[] PROGMEM = {
   0x00,0x00,0x00,0xF8,0xFF,0x03,0x80,0x20,0x00,0x40,0x40,0x00,0x40,0x40,0x00,0x40,0x40,0x00,0x80,0x20,0x00,0x00,0x1F, // 254
   0xC0,0x01,0x00,0x00,0x06,0x02,0x10,0x38,0x02,0x00,0xE0,0x01,0x10,0x38,0x00,0x00,0x07,0x00,0xC0  // 255
 };
-const unsigned char ArialMT_Plain_24[] PROGMEM = {
+const uint8_t ArialMT_Plain_24[] PROGMEM = {
   0x18, // Width: 24
   0x1C, // Height: 28
   0x20, // First Char: 32
@@ -1271,4 +1271,4 @@ const unsigned char ArialMT_Plain_24[] PROGMEM = {
   0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xE0,0xFF,0xFF,0x07,0xE0,0xFF,0xFF,0x07,0x00,0x1C,0x18,0x00,0x00,0x06,0x30,0x00,0x00,0x06,0x30,0x00,0x00,0x06,0x30,0x00,0x00,0x0E,0x38,0x00,0x00,0x1C,0x1C,0x00,0x00,0xF8,0x0F,0x00,0x00,0xF0,0x03, // 254
   0x00,0x00,0x00,0x00,0x00,0x0E,0x00,0x00,0x00,0x7E,0x00,0x06,0xC0,0xF0,0x01,0x06,0xC0,0x80,0x0F,0x07,0x00,0x00,0xFE,0x03,0x00,0x00,0xFC,0x00,0xC0,0xC0,0x1F,0x00,0xC0,0xF8,0x03,0x00,0x00,0x3E,0x00,0x00,0x00,0x06 // 255
 };
-#endif 
+#endif
diff --git a/OLEDDisplayUi.cpp b/OLEDDisplayUi.cpp
index cea3bb5d37aafb289fb1acb1065dd5565a95acf1..f9b8370fb445e72024c5f8f23040ff860404bdb1 100644
--- a/OLEDDisplayUi.cpp
+++ b/OLEDDisplayUi.cpp
@@ -90,10 +90,10 @@ void OLEDDisplayUi::setIndicatorPosition(IndicatorPosition pos) {
 void OLEDDisplayUi::setIndicatorDirection(IndicatorDirection dir) {
   this->indicatorDirection = dir;
 }
-void OLEDDisplayUi::setActiveSymbol(const unsigned char* symbol) {
+void OLEDDisplayUi::setActiveSymbol(const uint8_t* symbol) {
   this->activeSymbol = symbol;
 }
-void OLEDDisplayUi::setInactiveSymbol(const unsigned char* symbol) {
+void OLEDDisplayUi::setInactiveSymbol(const uint8_t* symbol) {
   this->inactiveSymbol = symbol;
 }
 
@@ -361,7 +361,7 @@ void OLEDDisplayUi::drawIndicator() {
     }
 
     uint16_t frameStartPos = (12 * frameCount / 2);
-    const unsigned char *image;
+    const uint8_t *image;
     uint16_t x,y;
     for (byte i = 0; i < this->frameCount; i++) {
 
diff --git a/OLEDDisplayUi.h b/OLEDDisplayUi.h
index ac2d9ed3c5266a1348550d5616c72a2f72f36f40..1e6372e157eedcab15770b373a74382dee2540c9 100644
--- a/OLEDDisplayUi.h
+++ b/OLEDDisplayUi.h
@@ -61,11 +61,11 @@ enum FrameState {
 };
 
 
-const unsigned char ANIMATION_activeSymbol[] PROGMEM = {
+const uint8_t ANIMATION_activeSymbol[] PROGMEM = {
   0x00, 0x18, 0x3c, 0x7e, 0x7e, 0x3c, 0x18, 0x00
 };
 
-const unsigned char ANIMATION_inactiveSymbol[] PROGMEM = {
+const uint8_t ANIMATION_inactiveSymbol[] PROGMEM = {
   0x00, 0x0, 0x0, 0x18, 0x18, 0x0, 0x0, 0x00
 };
 
@@ -106,8 +106,8 @@ class OLEDDisplayUi {
     IndicatorPosition   indicatorPosition         = BOTTOM;
     IndicatorDirection  indicatorDirection        = LEFT_RIGHT;
 
-    const unsigned char*         activeSymbol              = ANIMATION_activeSymbol;
-    const unsigned char*         inactiveSymbol            = ANIMATION_inactiveSymbol;
+    const uint8_t*         activeSymbol              = ANIMATION_activeSymbol;
+    const uint8_t*         inactiveSymbol            = ANIMATION_inactiveSymbol;
 
     bool                shouldDrawIndicators      = true;
 
@@ -240,12 +240,12 @@ class OLEDDisplayUi {
     /**
      * Set the symbol to indicate an active frame in the indicator bar.
      */
-    void setActiveSymbol(const unsigned char* symbol);
+    void setActiveSymbol(const uint8_t* symbol);
 
     /**
      * Set the symbol to indicate an inactive frame in the indicator bar.
      */
-    void setInactiveSymbol(const unsigned char* symbol);
+    void setInactiveSymbol(const uint8_t* symbol);
 
 
     // Frame settings
diff --git a/examples/SSD1306SimpleDemo/images.h b/examples/SSD1306SimpleDemo/images.h
index 5526ed4734b0d66797ded4e254caf391dd7a0cb3..50417990fd0d3d0854b4385afac1334d45223214 100644
--- a/examples/SSD1306SimpleDemo/images.h
+++ b/examples/SSD1306SimpleDemo/images.h
@@ -1,6 +1,6 @@
 #define WiFi_Logo_width 60
 #define WiFi_Logo_height 36
-const unsigned char WiFi_Logo_bits[] PROGMEM = {
+const uint8_t WiFi_Logo_bits[] PROGMEM = {
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF8,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80, 0xFF, 0x07, 0x00, 0x00, 0x00,
   0x00, 0x00, 0xE0, 0xFF, 0x1F, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF8, 0xFF,
diff --git a/examples/SSD1306UiDemo/images.h b/examples/SSD1306UiDemo/images.h
index 662bd1f8c75702ab2e777e41f8c65924668614a6..2489d1e5de658663f1bf16b456b18743193cf1c0 100644
--- a/examples/SSD1306UiDemo/images.h
+++ b/examples/SSD1306UiDemo/images.h
@@ -1,6 +1,6 @@
 #define WiFi_Logo_width 60
 #define WiFi_Logo_height 36
-const unsigned char WiFi_Logo_bits[] PROGMEM = {
+const uint8_t WiFi_Logo_bits[] PROGMEM = {
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF8,
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80, 0xFF, 0x07, 0x00, 0x00, 0x00,
   0x00, 0x00, 0xE0, 0xFF, 0x1F, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF8, 0xFF,
@@ -27,7 +27,7 @@ const unsigned char WiFi_Logo_bits[] PROGMEM = {
   0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   };
 
-const unsigned char activeSymbol[] PROGMEM = {
+const uint8_t activeSymbol[] PROGMEM = {
     B00000000,
     B00000000,
     B00011000,
@@ -38,7 +38,7 @@ const unsigned char activeSymbol[] PROGMEM = {
     B00011000
 };
 
-const unsigned char inactiveSymbol[] PROGMEM = {
+const uint8_t inactiveSymbol[] PROGMEM = {
     B00000000,
     B00000000,
     B00000000,