diff --git a/Firmware/Configuration.h b/Firmware/Configuration.h
index d1d0b8ab9..eba8eb67f 100644
--- a/Firmware/Configuration.h
+++ b/Firmware/Configuration.h
@@ -722,4 +722,5 @@ enum CalibrationStatus
 
 #include "Configuration_adv.h"
 #include "thermistortables.h"
+
 #endif //__CONFIGURATION_H
diff --git a/Firmware/cardreader.cpp b/Firmware/cardreader.cpp
index a9ee7e574..f41f20ac7 100644
--- a/Firmware/cardreader.cpp
+++ b/Firmware/cardreader.cpp
@@ -81,7 +81,7 @@ void CardReader::lsDive(const char *prepend, SdFile parent, const char * const m
         if(lsAction==LS_SerialPrint)
         {
           SERIAL_ECHO_START;
-          SERIAL_ECHOLN(MSG_SD_CANT_OPEN_SUBDIR);
+          SERIAL_ECHORPGM(MSG_SD_CANT_ENTER_SUBDIR);
           SERIAL_ECHOLN(lfilename);
         }
       }
diff --git a/Firmware/variants/1_75mm_MK2-RAMBo10a-E3Dv6full.h b/Firmware/variants/1_75mm_MK2-RAMBo10a-E3Dv6full.h
index 2c49e68a8..3e89889aa 100644
--- a/Firmware/variants/1_75mm_MK2-RAMBo10a-E3Dv6full.h
+++ b/Firmware/variants/1_75mm_MK2-RAMBo10a-E3Dv6full.h
@@ -37,7 +37,7 @@ const bool Z_MIN_ENDSTOP_INVERTING = false; // set to true to invert the logic o
 #define MANUAL_Z_HOME_POS 0.15
 
 // Travel limits after homing
-#define X_MAX_POS 255
+#define X_MAX_POS 250
 #define X_MIN_POS 0
 #define Y_MAX_POS 210
 #define Y_MIN_POS -2.2
@@ -93,20 +93,18 @@ EXTRUDER SETTINGS
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 
+// Prusa Single extruder multiple material suport
+//#define SNMM
 
+#ifdef SNMM
+//#define BOWDEN_LENGTH	408
+#define BOWDEN_LENGTH 457 //total length for filament fast loading part; max length for extrusion is 465 mm!
+#define FIL_LOAD_LENGTH 102 //length for loading filament into the nozzle
+#define FIL_RETURN_LENGTH 30.5 //for filament adjusting (PRUSAY code)
+#define E_MOTOR_LOW_CURRENT 350 // current for PRUSAY code
+#define E_MOTOR_HIGH_CURRENT 700 //current for unloading filament, stop print, PRUSAY ramming
 
-/*------------------------------------
-LOAD/UNLOAD FILAMENT SETTINGS
-*------------------------------------*/
-
-// Load filament commands
-#define LOAD_FILAMENT_0 "M83"
-#define LOAD_FILAMENT_1 "G1 E70 F400"
-#define LOAD_FILAMENT_2 "G1 E40 F100"
-
-// Unload filament commands
-#define UNLOAD_FILAMENT_0 "M83"
-#define UNLOAD_FILAMENT_1 "G1 E-80 F7000"
+#endif
 
 /*------------------------------------
 CHANGE FILAMENT SETTINGS
@@ -312,5 +310,22 @@ THERMISTORS SETTINGS
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_BED 1
 
+#define STACK_GUARD_TEST_VALUE 0xA2A2
+
+#define MAX_BED_TEMP_CALIBRATION 50
+#define MAX_HOTEND_TEMP_CALIBRATION 50
+
+#define MAX_E_STEPS_PER_UNIT 250
+#define MIN_E_STEPS_PER_UNIT 100
+
+#define PRINT_STARTED 0xFE
+#define PRINT_FINISHED 0xFF
+
+#define Z_BABYSTEP_MIN -3999
+#define Z_BABYSTEP_MAX 0
+
+#define PING_TIME 60 //time in s
+#define PING_TIME_LONG 600 //10 min; used when length of commands buffer > 0 to avoid false triggering when dealing with long gcodes
+#define PING_ALLERT_PERIOD 60 //time in s
 
 #endif //__CONFIGURATION_PRUSA_H
diff --git a/Firmware/variants/1_75mm_MK2-RAMBo13a-E3Dv6full.h b/Firmware/variants/1_75mm_MK2-RAMBo13a-E3Dv6full.h
index c7e3ecb8a..a36f3c9a3 100644
--- a/Firmware/variants/1_75mm_MK2-RAMBo13a-E3Dv6full.h
+++ b/Firmware/variants/1_75mm_MK2-RAMBo13a-E3Dv6full.h
@@ -37,7 +37,7 @@ const bool Z_MIN_ENDSTOP_INVERTING = false; // set to true to invert the logic o
 #define MANUAL_Z_HOME_POS 0.15
 
 // Travel limits after homing
-#define X_MAX_POS 255
+#define X_MAX_POS 250
 #define X_MIN_POS 0
 #define Y_MAX_POS 210
 #define Y_MIN_POS -2.2
@@ -93,20 +93,18 @@ EXTRUDER SETTINGS
 #define EXTRUDER_AUTO_FAN_TEMPERATURE 50
 #define EXTRUDER_AUTO_FAN_SPEED   255  // == full speed
 
+// Prusa Single extruder multiple material suport
+//#define SNMM
 
+#ifdef SNMM
+//#define BOWDEN_LENGTH	408
+#define BOWDEN_LENGTH 457 //total length for filament fast loading part; max length for extrusion is 465 mm!
+#define FIL_LOAD_LENGTH 102 //length for loading filament into the nozzle
+#define FIL_RETURN_LENGTH 30.5 //for filament adjusting (PRUSAY code)
+#define E_MOTOR_LOW_CURRENT 350 // current for PRUSAY code
+#define E_MOTOR_HIGH_CURRENT 700 //current for unloading filament, stop print, PRUSAY ramming
 
-/*------------------------------------
-LOAD/UNLOAD FILAMENT SETTINGS
-*------------------------------------*/
-
-// Load filament commands
-#define LOAD_FILAMENT_0 "M83"
-#define LOAD_FILAMENT_1 "G1 E70 F400"
-#define LOAD_FILAMENT_2 "G1 E40 F100"
-
-// Unload filament commands
-#define UNLOAD_FILAMENT_0 "M83"
-#define UNLOAD_FILAMENT_1 "G1 E-80 F7000"
+#endif
 
 /*------------------------------------
 CHANGE FILAMENT SETTINGS
@@ -312,5 +310,22 @@ THERMISTORS SETTINGS
 #define TEMP_SENSOR_2 0
 #define TEMP_SENSOR_BED 1
 
+#define STACK_GUARD_TEST_VALUE 0xA2A2
+
+#define MAX_BED_TEMP_CALIBRATION 50
+#define MAX_HOTEND_TEMP_CALIBRATION 50
+
+#define MAX_E_STEPS_PER_UNIT 250
+#define MIN_E_STEPS_PER_UNIT 100
+
+#define PRINT_STARTED 0xFE
+#define PRINT_FINISHED 0xFF
+
+#define Z_BABYSTEP_MIN -3999
+#define Z_BABYSTEP_MAX 0
+
+#define PING_TIME 60 //time in s
+#define PING_TIME_LONG 600 //10 min; used when length of commands buffer > 0 to avoid false triggering when dealing with long gcodes
+#define PING_ALLERT_PERIOD 60 //time in s
 
 #endif //__CONFIGURATION_PRUSA_H