- The numeric password can be of any length of our choice ( max.length 15).
- Password programmable by SMS from a unique authorised number.
- SMS Commands, Alerts , Maximum 3 wrong attempts , Emergency freeze mode for increased security.
- Developer : Mitu Raj
Step 1: Components Required
2) SIM 900A GSM module
3) 4x4 matrix keypad
4) 5V Relay Module
5) 16x2 LCD display
Step 2: Circuit Connection
1) 4x4 Keypad pins 1-8 are connected to D2-D9 pins of Arduino. If you get incorrect response from the keypad , it maybe because you connected it in the reverse order. Take a note of this.
2) SIM 900A GSM module's RX and TX are connected to D11, D10 respectively. We use these pins as software serial . GND of GSM is connected to Arduino GND .
3) Use 9V 2A adapter as power supply to GSM module. 2A is preferred over 1A rated adapter. The same may be used to power the Arduino too. Your wish.
4) The 5V relay module is connected to D12 pin. and "Busy" status LED . Choose the relay wisely ( generally capable to switch 24V DC/ 240V AC 5A rating).
5) Interface the LCD display as in the circuit diagram shown.
You are ready to GO !!!
Note : The Led in 13th pin is connected in reverse manner in the circuit diagram . please connect the positive of the Led to the Vcc of the arduino , and the negative to D13 via the resistor . Also connect the analog pins to LCD in the reverse order to that in the circuit diagram .
Step 3: Notes
link to my paper :
For any queries please contact me @firstname.lastname@example.org
Thank You !
mail : email@example.com