Write the program, plug in the USB cable, burn the code to the Mars board. After upload is done, open the Serial Monitor.

Remember to inlcude the library below:

/*

|| || @file Keypad.h || @version 3.1 || @author Mark Stanley, Alexander Brevig || @contact mstanley@technologist.com, alexanderbrevig@gmail.com || || @description || | This library provides a simple interface for using matrix || | keypads. It supports multiple keypresses while maintaining || | backwards compatibility with the old single key library. || | It also supports user selectable pins and definable keymaps. || # || || @license || | This library is free software; you can redistribute it and/or || | modify it under the terms of the GNU Lesser General Public || | License as published by the Free Software Foundation; version || | 2.1 of the License. || | || | This library is distributed in the hope that it will be useful, || | but WITHOUT ANY WARRANTY; without even the implied warranty of || | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU || | Lesser General Public License for more details. || | || | You should have received a copy of the GNU Lesser General Public || | License along with this library; if not, write to the Free Software || | Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA || # || */ #ifndef KEYPAD_H #define KEYPAD_H #include "utility/Key.h" // Arduino versioning. #if defined(ARDUINO) && ARDUINO >= 100 #include "Arduino.h" #else #include "WProgram.h" #endif // bperrybap - Thanks for a well reasoned argument and the following macro(s). // See http://arduino.cc/forum/index.php/topic,142041.msg1069480.html#msg1069480 #ifndef INPUT_PULLUP #warning "Using pinMode() INPUT_PULLUP AVR emulation" #define INPUT_PULLUP 0x2 #define pinMode(_pin, _mode) _mypinMode(_pin, _mode) #define _mypinMode(_pin, _mode) \ do { \ if(_mode == INPUT_PULLUP) \ pinMode(_pin, INPUT); \ digitalWrite(_pin, 1); \ if(_mode != INPUT_PULLUP) \ pinMode(_pin, _mode); \ }while(0) #endif #define OPEN LOW #define CLOSED HIGH typedef char KeypadEvent; typedef unsigned int uint; typedef unsigned long ulong; // Made changes according to this post http://arduino.cc/forum/index.php?topic=58337.0 // by Nick Gammon. Thanks for the input Nick. It actually saved 78 bytes for me. :) typedef struct { byte rows; byte columns; } KeypadSize; #define LIST_MAX 10 // Max number of keys on the active list. #define MAPSIZE 10 // MAPSIZE is the number of rows (times 16 columns) #define makeKeymap(x) ((char*)x) //class Keypad : public Key, public HAL_obj { class Keypad : public Key { public: Keypad(char *userKeymap, byte *row, byte *col, byte numRows, byte numCols); virtual void pin_mode(byte pinNum, byte mode) { pinMode(pinNum, mode); } virtual void pin_write(byte pinNum, boolean level) { digitalWrite(pinNum, level); } virtual int pin_read(byte pinNum) { return digitalRead(pinNum); } uint bitMap[MAPSIZE]; // 10 row x 16 column array of bits. Except Due which has 32 columns. Key key[LIST_MAX]; unsigned long holdTimer; char getKey(); bool getKeys(); KeyState getState(); void begin(char *userKeymap); bool isPressed(char keyChar); void setDebounceTime(uint); void setHoldTime(uint); void addEventListener(void (*listener)(char)); int findInList(char keyChar); int findInList(int keyCode); char waitForKey(); bool keyStateChanged(); byte numKeys(); private: unsigned long startTime; char *keymap; byte *rowPins; byte *columnPins; KeypadSize sizeKpd; uint debounceTime; uint holdTime; bool single_key; void scanKeys(); bool updateList(); void nextKeyState(byte n, boolean button); void transitionTo(byte n, KeyState nextState); void (*keypadEventListener)(char); }; #endif /* || @changelog || | 3.1 2013-01-15 - Mark Stanley : Fixed missing RELEASED & IDLE status when using a single key. || | 3.0 2012-07-12 - Mark Stanley : Made library multi-keypress by default. (Backwards compatible) || | 3.0 2012-07-12 - Mark Stanley : Modified pin functions to support Keypad_I2C || | 3.0 2012-07-12 - Stanley & Young : Removed static variables. Fix for multiple keypad objects. || | 3.0 2012-07-12 - Mark Stanley : Fixed bug that caused shorted pins when pressing multiple keys. || | 2.0 2011-12-29 - Mark Stanley : Added waitForKey(). || | 2.0 2011-12-23 - Mark Stanley : Added the public function keyStateChanged(). || | 2.0 2011-12-23 - Mark Stanley : Added the private function scanKeys(). || | 2.0 2011-12-23 - Mark Stanley : Moved the Finite State Machine into the function getKeyState(). || | 2.0 2011-12-23 - Mark Stanley : Removed the member variable lastUdate. Not needed after rewrite. || | 1.8 2011-11-21 - Mark Stanley : Added test to determine which header file to compile, || | WProgram.h or Arduino.h. || | 1.8 2009-07-08 - Alexander Brevig : No longer uses arrays || | 1.7 2009-06-18 - Alexander Brevig : This library is a Finite State Machine every time a state changes || | the keypadEventListener will trigger, if set || | 1.7 2009-06-18 - Alexander Brevig : Added setDebounceTime setHoldTime specifies the amount of || | microseconds before a HOLD state triggers || | 1.7 2009-06-18 - Alexander Brevig : Added transitionTo || | 1.6 2009-06-15 - Alexander Brevig : Added getState() and state variable || | 1.5 2009-05-19 - Alexander Brevig : Added setHoldTime() || | 1.4 2009-05-15 - Alexander Brevig : Added addEventListener || | 1.3 2009-05-12 - Alexander Brevig : Added lastUdate, in order to do simple debouncing || | 1.2 2009-05-09 - Alexander Brevig : Changed getKey() || | 1.1 2009-04-28 - Alexander Brevig : Modified API, and made variables private || | 1.0 2007-XX-XX - Mark Stanley : Initial Release || # */

Here is the code:

<p>/*******************************************************<br> name:Password Lock function: the I2C LCD1602 will display "Welcome!" after power on. At this point, the indicator LED on the relay keeps off. When you press "*" key, it will prompt "Input Your Code:". If you enter “123456” and press “#” key to confirm, the indicator LED on the relay module will light up. The I2C LCD1602 will display "Input Correctly" "Please Come In". Two seconds later, "Welcome!" *********************************************************/ //Email:support@sunfounder.com //Website:www.sunfounder.com</p><p>#include #include //use the servo Servo myservo; //Declare the servo</p><p>const byte ROWS = 4; //four rows const byte COLS = 4; //four columns //define the cymbols on the buttons of the keypads char hexaKeys[ROWS][COLS] = { { '1', '2', '3', '4' }, { '5', '6', '7', '8' }, { '9', 'A', 'B', 'C' }, { 'D', '*', '0', '#' } }; //行 byte rowPins[ROWS] = { 2, 3, 4, 5 }; //列 byte colPins[COLS] = { 6, 7, 8, 9 };</p><p>int pos = 0; char secretCode[6] = { '1', '2', '3', '4', '5', '6'}; char inputCode[6] = { '0', '0', '0', '0', '0', '0'};</p><p>//initialize an instance of class NewKeypad Keypad customKeypad = Keypad( makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS);</p><p>void setup() {</p><p> Serial.begin(9600); delay(2000); pinMode(11, OUTPUT); //绿灯 pinMode(12, OUTPUT); //绿灯 myservo.attach(10); //舵机digital pin 10</p><p>}</p><p>void loop() { readKey(); }</p><p>void readKey() { int correct = 0; int i; char customKey = customKeypad.getKey();//get the key value</p><p> if (customKey) {</p><p> switch (customKey) { case '*': //if press in "*" ,then print "Input Your Code:" pos = 0; Serial.println("Input Your Code: "); break; case '#': //if press in "#" ,then see the password whether "1 2 3 4 5 6" for (i = 0; i < 6; i++) { if (inputCode[i] == secretCode[i]) { correct ++; } } if (correct == 6) //if it right { Serial.println("Input correctly!"); digitalWrite(11, HIGH); //relay connected digitalWrite(12, LOW); for (int i = 0; i < 120; i++) { myservo.write(i); delay(10); } for (int i = 120; i > 0; i--) { myservo.write(i); delay(10); } for (int i = 0; i < 120; i++) { myservo.write(i); delay(10); } for (int i = 120; i > 0; i--) { myservo.write(i); delay(10); } } else { Serial.println("Input Error!"); digitalWrite(12, HIGH); digitalWrite(11, LOW); } break; default: inputCode[pos] = customKey; Serial.println(inputCode[pos]); pos ++;</p><p> } } }</p>