transmitter:18: error: 'U8G2_SSD1306_128X32_UNIVISION_1_HW_I2C' does not name a type

[StefanMeGit]

I run into an issue while compiling your build. What did I wrong?

I installed following libraries:

U8g2
RF24
U8glib
VescUartControlMaster

all the newest version.

Arduino: 1.8.5 (Mac OS X), Board: "Arduino Nano, ATmega328P"

Build options changed, rebuilding all
/Users/XXXXXXX/Downloads/nRF24-Esk8-Remote-master/transmitter/transmitter.ino: In function 'void setup()':
transmitter:160: error: 'u8g2' was not declared in this scope
   u8g2.begin();
   ^
/Users/XXXXXXX/Downloads/nRF24-Esk8-Remote-master/transmitter/transmitter.ino: In function 'void drawSettingNumber()':
transmitter:267: error: 'u8g2' was not declared in this scope
   u8g2.drawRFrame(x + 102, y - 10, 22, 32, 4);
   ^
transmitter:273: error: 'u8g2_font_profont22_tn' was not declared in this scope
   u8g2.setFont(u8g2_font_profont22_tn);
                ^
/Users/XXXXXXX/Downloads/nRF24-Esk8-Remote-master/transmitter/transmitter.ino: In function 'void drawSettingsMenu()':
transmitter:285: error: 'u8g2' was not declared in this scope
   u8g2.setFont(u8g2_font_profont12_tr);
   ^
transmitter:285: error: 'u8g2_font_profont12_tr' was not declared in this scope
   u8g2.setFont(u8g2_font_profont12_tr);
                ^
transmitter:292: error: 'u8g2_font_10x20_tr' was not declared in this scope
   u8g2.setFont(u8g2_font_10x20_tr  );
                ^
/Users/XXXXXXX/Downloads/nRF24-Esk8-Remote-master/transmitter/transmitter.ino: In function 'void updateMainDisplay()':
transmitter:488: error: 'u8g2' was not declared in this scope
   u8g2.firstPage();
   ^
/Users/XXXXXXX/Downloads/nRF24-Esk8-Remote-master/transmitter/transmitter.ino: In function 'void drawStartScreen()':
transmitter:505: error: 'u8g2' was not declared in this scope
   u8g2.firstPage();
   ^
transmitter:511: error: 'u8g2_font_helvR10_tr' was not declared in this scope
     u8g2.setFont(u8g2_font_helvR10_tr  );
                  ^
/Users/XXXXXXX/Downloads/nRF24-Esk8-Remote-master/transmitter/transmitter.ino: In function 'void drawTitleScreen(String)':
transmitter:518: error: 'u8g2' was not declared in this scope
   u8g2.firstPage();
   ^
transmitter:521: error: 'u8g2_font_helvR10_tr' was not declared in this scope
     u8g2.setFont(u8g2_font_helvR10_tr  );
                  ^
/Users/XXXXXXX/Downloads/nRF24-Esk8-Remote-master/transmitter/transmitter.ino: In function 'void drawPage()':
transmitter:573: error: 'u8g2' was not declared in this scope
   u8g2.setFont(u8g2_font_profont12_tr);
   ^
transmitter:573: error: 'u8g2_font_profont12_tr' was not declared in this scope
   u8g2.setFont(u8g2_font_profont12_tr);
                ^
transmitter:589: error: 'u8g2_font_logisoso22_tn' was not declared in this scope
   u8g2.setFont(u8g2_font_logisoso22_tn );
                ^
/Users/XXXXXXX/Downloads/nRF24-Esk8-Remote-master/transmitter/transmitter.ino: In function 'void drawThrottle()':
transmitter:611: error: 'u8g2' was not declared in this scope
   u8g2.drawHLine(x, y, 52);
   ^
/Users/XXXXXXX/Downloads/nRF24-Esk8-Remote-master/transmitter/transmitter.ino: In function 'void drawSignal()':
transmitter:644: error: 'u8g2' was not declared in this scope
       u8g2.drawXBM(x, y, 12, 12, signal_transmitting_bits);
       ^
transmitter:646: error: 'u8g2' was not declared in this scope
       u8g2.drawXBM(x, y, 12, 12, signal_connected_bits);
       ^
transmitter:655: error: 'u8g2' was not declared in this scope
       u8g2.drawXBM(x, y, 12, 12, signal_connected_bits);
       ^
transmitter:657: error: 'u8g2' was not declared in this scope
       u8g2.drawXBM(x, y, 12, 12, signal_noconnection_bits);
       ^
/Users/XXXXXXX/Downloads/nRF24-Esk8-Remote-master/transmitter/transmitter.ino: In function 'void drawBatteryLevel()':
transmitter:668: error: 'u8g2' was not declared in this scope
   u8g2.drawFrame(x + 2, y, 18, 9);
   ^
exit status 1
'u8g2' was not declared in this scope

This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

[StefanMeGit]

I tried the development branch... worked without any problems. Is it safe to use?