HELP : create connection with arduino 3Dprinter

Hello !

I'm trying to connect grasshopper to my Arduino Printer (Tractus3D Delta-printer).

Steps I have taken: grasshopper-firefly-arduino(firmata)-arduino Mega 2560.

I'm not an IT'er so I don't understand everything and I need help.

Below: I have found in Marlin the pins of X,Y,Z,... but I don't know how to connect them and get response. In Firefly "Uno write" we have just pins 3,5,6,8,9,10,11,12,13 and I see more pins below.And what's the difference between Digital/PWM/Servo.

All help is very  appreciated !

/****************************************************************************************

#define X_STEP_PIN       49
#define X_DIR_PIN        13
#define X_ENABLE_PIN     48
#define X_MIN_PIN        35
#define X_MAX_PIN        -1 //34

#define Y_STEP_PIN         11
#define Y_DIR_PIN          9
#define Y_ENABLE_PIN       12
#define Y_MIN_PIN          33
#define Y_MAX_PIN          -1 //32

#define Z_STEP_PIN         7
#define Z_DIR_PIN          6
#define Z_ENABLE_PIN       8
#define Z_MIN_PIN          31
#define Z_MAX_PIN          -1 //30

#define E2_STEP_PIN        43
#define E2_DIR_PIN         47
#define E2_ENABLE_PIN      42

#define E1_STEP_PIN        18
#define E1_DIR_PIN         19
#define E1_ENABLE_PIN      38

#define E0_STEP_PIN        40
#define E0_DIR_PIN         41
#define E0_ENABLE_PIN      37

#define SDPOWER            -1
#define LED_PIN            -1 //Use +12V Aux port for LED Ring

#define FAN_PIN            16 //5V PWM

#define PS_ON_PIN          10 //Set to -1 if using a manual switch on the PWRSW Connector
#define SLEEP_WAKE_PIN   26 //This feature still needs work

#define HEATER_0_PIN       45 //12V PWM1
#define HEATER_1_PIN       46 //12V PWM2
#define HEATER_2_PIN       17 //12V PWM3
#define HEATER_BED_PIN     44 //DOUBLE 12V PWM
#define TEMP_0_PIN         3 //ANALOG NUMBERING
#define TEMP_1_PIN         2  //ANALOG NUMBERING
#define TEMP_2_PIN         1  //ANALOG NUMBERING
#define TEMP_BED_PIN       0 //ANALOG NUMBERING

#define BEEPER            36

#define KILL_PIN           -1