added contrast control function for gLCDs

Marlin/Configuration.h

   #endif
 #endif
 
+// default LCD contrast for dogm-like LCD displays
+#ifdef DOGLCD
+# ifndef DEFAULT_LCD_CONTRAST
+#  define DEFAULT_LCD_CONTRAST 32
+# endif
+#endif
+
 // Increase the FAN pwm frequency. Removes the PWM noise but increases heating in the FET/Arduino
 //#define FAST_PWM_FAN
 

Marlin/ConfigurationStore.cpp

 // the default values are used whenever there is a change to the data, to prevent
 // wrong data being written to the variables.
 // ALSO:  always make sure the variables in the Store and retrieve sections are in the same order.
-#define EEPROM_VERSION "V07"
+#define EEPROM_VERSION "V08"
 
 #ifdef EEPROM_SETTINGS
 void Config_StoreSettings() 
     EEPROM_WRITE_VAR(i,dummy);
     EEPROM_WRITE_VAR(i,dummy);
   #endif
+  #ifndef DOGLCD
+    int lcd_contrast = 32;
+  #endif
+  EEPROM_WRITE_VAR(i,lcd_contrast);
   char ver2[4]=EEPROM_VERSION;
   i=EEPROM_OFFSET;
   EEPROM_WRITE_VAR(i,ver2); // validate data
         EEPROM_READ_VAR(i,Kp);
         EEPROM_READ_VAR(i,Ki);
         EEPROM_READ_VAR(i,Kd);
+        #ifndef DOGLCD
+        int lcd_contrast;
+        #endif
+        EEPROM_READ_VAR(i,lcd_contrast);
 
 		// Call updatePID (similar to when we have processed M301)
 		updatePID();
     absPreheatHPBTemp = ABS_PREHEAT_HPB_TEMP;
     absPreheatFanSpeed = ABS_PREHEAT_FAN_SPEED;
 #endif
+#ifdef DOGLCD
+    lcd_contrast = DEFAULT_LCD_CONTRAST;
+#endif
 #ifdef PIDTEMP
     Kp = DEFAULT_Kp;
     Ki = scalePID_i(DEFAULT_Ki);

Marlin/Marlin_main.cpp

 // M220 S<factor in percent>- set speed factor override percentage
 // M221 S<factor in percent>- set extrude factor override percentage
 // M240 - Trigger a camera to take a photograph
+// M250 - Set LCD contrast C<contrast value> (value 0..63)
 // M280 - set servo position absolute. P: servo index, S: angle or microseconds
 // M300 - Play beepsound S<frequency Hz> P<duration ms>
 // M301 - Set PID parameters P I and D
   servo_init();
 
   lcd_init();
+  _delay_ms(1000);	// wait 1sec to display the splash screen
   
   #if defined(CONTROLLERFAN_PIN) && CONTROLLERFAN_PIN > -1
     SET_OUTPUT(CONTROLLERFAN_PIN); //Set pin used for driver cooling fan
       #endif
      }
     break;
+#ifdef DOGLCD
+    case 250: // M250  Set LCD contrast value: C<value> (value 0..63)
+     {
+	  if (code_seen('C')) {
+	   lcd_setcontrast( ((int)code_value())&63 );
+          }
+          SERIAL_PROTOCOLPGM("lcd contrast value: ");
+          SERIAL_PROTOCOL(lcd_contrast);
+          SERIAL_PROTOCOLLN("");
+     }
+    break;
+#endif
     #ifdef PREVENT_DANGEROUS_EXTRUDE
     case 302: // allow cold extrudes, or set the minimum extrude temperature
     {

Marlin/dogm_lcd_implementation.h

 
 #define FONT_STATUSMENU	u8g_font_6x9
 
+int lcd_contrast;
+
 // LCD selection
 #ifdef U8GLIB_ST7920
 //U8GLIB_ST7920_128X64_RRD u8g(0,0,0);
 
 static void lcd_implementation_init()
 {
+#ifdef LCD_PIN_BL
+	pinMode(LCD_PIN_BL, OUTPUT);	// Enable LCD backlight
+	digitalWrite(LCD_PIN_BL, HIGH);
+#endif
+
+        u8g.setContrast(lcd_contrast);	
 	//  Uncomment this if you have the first generation (V1.10) of STBs board
 	//  pinMode(17, OUTPUT);	// Enable LCD backlight
 	//  digitalWrite(17, HIGH);
 			u8g.setFont(u8g_font_6x10_marlin);
 			u8g.drawStr(62,10,"MARLIN"); 
 			u8g.setFont(u8g_font_5x8);
-			u8g.drawStr(62,19,"V1.0.0 RC2");
+			u8g.drawStr(62,19,"V1.0.0 RC2-mm");
 			u8g.setFont(u8g_font_6x10_marlin);
 			u8g.drawStr(62,28,"by ErikZalm");
 			u8g.drawStr(62,41,"DOGM128 LCD");
 			u8g.setFont(u8g_font_5x8);
 			u8g.drawStr(62,48,"enhancements");
 			u8g.setFont(u8g_font_5x8);
-			u8g.drawStr(62,55,"by STB");
+			u8g.drawStr(62,55,"by STB, MM");
 			u8g.drawStr(62,61,"uses u");
 			u8g.drawStr90(92,57,"8");
 			u8g.drawStr(100,61,"glib");

Marlin/language.h

 	#define MSG_RECTRACT "Rectract"
 	#define MSG_TEMPERATURE "Temperature"
 	#define MSG_MOTION "Motion"
+	#define MSG_CONTRAST "LCD contrast"
 	#define MSG_STORE_EPROM "Store memory"
 	#define MSG_LOAD_EPROM "Load memory"
 	#define MSG_RESTORE_FAILSAFE "Restore Failsafe"
 	#define MSG_RECTRACT "Wycofanie"
 	#define MSG_TEMPERATURE "Temperatura"
 	#define MSG_MOTION "Ruch"
+	#define MSG_CONTRAST "LCD contrast"
 	#define MSG_STORE_EPROM "Zapisz w pamieci"
 	#define MSG_LOAD_EPROM "Wczytaj z pamieci"
 	#define MSG_RESTORE_FAILSAFE " Ustawienia fabryczne"
 #define MSG_TEMPERATURE_WIDE " Temperature \x7E"
 #define MSG_TEMPERATURE_RTN " Temperature \003"
 #define MSG_MOTION_WIDE " Mouvement \x7E"
+	#define MSG_CONTRAST "LCD contrast"
 #define MSG_STORE_EPROM " Sauvegarder memoire"
 #define MSG_LOAD_EPROM " Lire memoire"
 #define MSG_RESTORE_FAILSAFE " Restaurer memoire"
 
 	#define MSG_SD_INSERTED      "SDKarte erkannt"
 	#define MSG_SD_REMOVED       "SDKarte entfernt"
-	#define MSG_MAIN             "Hauptmneü"
+	#define MSG_MAIN             "Hauptmenü"
 	#define MSG_AUTOSTART        "Autostart"
 	#define MSG_DISABLE_STEPPERS "Stepper abschalten"
 	#define MSG_AUTO_HOME        "Auto Nullpunkt"
 	#define MSG_NOZZLE2          "Düse3"
 	#define MSG_BED              "Bett"
 	#define MSG_FAN_SPEED        "Lüftergeschw."
-	#define MSG_FLOW             "Fluß"
+	#define MSG_FLOW             "Fluss"
 	#define MSG_CONTROL          "Einstellungen"
 	#define MSG_MIN              "\002 Min"
 	#define MSG_MAX              "\002 Max"
 	#define MSG_WATCH            "Beobachten"
 	#define MSG_TEMPERATURE      "Temperatur"
 	#define MSG_MOTION           "Bewegung"
+	#define MSG_CONTRAST "LCD contrast"
 	#define MSG_STORE_EPROM      "EPROM speichern"
 	#define MSG_LOAD_EPROM       "EPROM laden"
 	#define MSG_RESTORE_FAILSAFE "Standardkonfig."
 #define MSG_RECTRACT    					" Откат подачи      \x7E"
 #define MSG_TEMPERATURE  				" Температура       \x7E"
 #define MSG_MOTION						" Скорости          \x7E"
+	#define MSG_CONTRAST "LCD contrast"
 #define MSG_STORE_EPROM						" Сохранить настройки"
 #define MSG_LOAD_EPROM						" Загрузить настройки"
 #define MSG_RESTORE_FAILSAFE				" Сброс настроек     "
 	#define MSG_RECTRACT             "Ritrai"
 	#define MSG_TEMPERATURE          "Temperatura"
 	#define MSG_MOTION               "Movimento"
+	#define MSG_CONTRAST "LCD contrast"
 	#define MSG_STORE_EPROM          "Salva in EEPROM"
 	#define MSG_LOAD_EPROM           "Carica da EEPROM"
 	#define MSG_RESTORE_FAILSAFE     "Impostaz. default"
 	#define MSG_RECTRACT "Veda takaisin"
 	#define MSG_TEMPERATURE "Lampotila"
 	#define MSG_MOTION "Liike"
+	#define MSG_CONTRAST "LCD contrast"
 	#define MSG_STORE_EPROM "Tallenna muistiin"
 	#define MSG_LOAD_EPROM "Lataa muistista"
 	#define MSG_RESTORE_FAILSAFE "Palauta oletus"

Marlin/ultralcd.cpp

 static void lcd_control_temperature_preheat_pla_settings_menu();
 static void lcd_control_temperature_preheat_abs_settings_menu();
 static void lcd_control_motion_menu();
+#ifdef DOGLCD
+static void lcd_set_contrast();
+#endif
 static void lcd_control_retract_menu();
 static void lcd_sdcard_menu();
 
     MENU_ITEM(back, MSG_MAIN, lcd_main_menu);
     MENU_ITEM(submenu, MSG_TEMPERATURE, lcd_control_temperature_menu);
     MENU_ITEM(submenu, MSG_MOTION, lcd_control_motion_menu);
+#ifdef DOGLCD
+//    MENU_ITEM_EDIT(int3, MSG_CONTRAST, &lcd_contrast, 0, 63);
+    MENU_ITEM(submenu, MSG_CONTRAST, lcd_set_contrast);
+#endif
 #ifdef FWRETRACT
     MENU_ITEM(submenu, MSG_RETRACT, lcd_control_retract_menu);
 #endif
     END_MENU();
 }
 
+#ifdef DOGLCD
+static void lcd_set_contrast()
+{
+    if (encoderPosition != 0)
+    {
+        lcd_contrast -= encoderPosition;
+        if (lcd_contrast < 0) lcd_contrast = 0;
+        else if (lcd_contrast > 63) lcd_contrast = 63;
+        encoderPosition = 0;
+        lcdDrawUpdate = 1;
+        u8g.setContrast(lcd_contrast);
+    }
+    if (lcdDrawUpdate)
+    {
+        lcd_implementation_drawedit(PSTR("Contrast"), itostr2(lcd_contrast));
+    }
+    if (LCD_CLICKED)
+    {
+        lcd_quick_feedback();
+        currentMenu = lcd_control_menu;
+        encoderPosition = 0;
+    }
+}
+#endif
+
 #ifdef FWRETRACT
 static void lcd_control_retract_menu()
 {
     lcd_status_message_level = 0;
 }
 
+#ifdef DOGLCD
+void lcd_setcontrast(uint8_t value)
+{
+    lcd_contrast = value & 63;
+    u8g.setContrast(lcd_contrast);	
+}
+#endif
+
 #ifdef ULTIPANEL
 /* Warning: This function is called from interrupt context */
 void lcd_buttons_update()

Marlin/ultralcd.h

   void lcd_setstatuspgm(const char* message);
   void lcd_setalertstatuspgm(const char* message);
   void lcd_reset_alert_level();
-  
+
+#ifdef DOGLCD
+  extern int lcd_contrast;
+  void lcd_setcontrast(uint8_t value);
+#endif
+
   static unsigned char blink = 0;	// Variable for visualisation of fan rotation in GLCD
 
   #define LCD_MESSAGEPGM(x) lcd_setstatuspgm(PSTR(x))