DTMF Based Door Opener System
Entry into a residence
is still primarily limited to a manual process which involves inserting a key
into a bolt and physically moving the locking mechanism. and its required
physical involvement of person sometimes it’s too difficult for person with
disability to open or close the door also it is not complete secure method if
someone finds the key of lock then it is easy to open the door without owner’s
permission. so we required the mechanism that develop remote devices and also reduces
the human efforts and maintenance cost
So here we are
introducing DTMF Cell Phone Based Door Opener System in which door is opened by
using mobile phone where users entered the unique password to open/closed the door. To activate the mobile phone unit, the
caller has to make a call which is connected to door. Then the user has to
enter the password. As the caller enters a specific password, to open the doors
If the password is wrongly entered four times in a row, from the interface – an
error sound is generated. And thus, security is kept intact because these
passwords are known and owned by selected persons only. DTMF frequencies are
more practical and less expensive to implement than the other signalling method
used by rotary telephones
.
Block diagram:
This
project includes DTMF {dual tone multi frequency} tones are composed of a series of low frequencies for each
column of keys and a series of high frequencies for each row of keys. Each
pressed key creates a signal that is equal to the sum of the column’s low
frequency and the row’s high frequencies. When the signal is sent over the
telephone line to the telephone company’s switching center, a DTMF decoder
separates the signal back into the two frequencies and passes it along to the
recipient’s phone. The DTMF decoder is responsible for doing this for all
telephone numbers entered by all callers in its designated area every day.
When
user wants to open the door he need to make a call on mobile which is connected
to door. Once the key or password is entered by person it will check with key which
is stored in 8085 microcontroller memory if the password is
successful, then microcontroller initiates the mechanism to open the door and grant
entrance. This automation introduces a form of secure,
keyless entry into a residence along with the convenience of a fully responsive
security system monitor.
Hardware
specification
·
8051
Microcontroller
·
Power
supply
·
DTMF
decoder circuit
·
Cell
phone
Software Specifications
·
MC Programming Language: Embedded C
·
Keil
version IDE
·
Proteus
For Circuit &PCB Design
