Security Alarm System (PIC16F877A)

Posted on Feb 8, 2013

This system uses a Microchip's PIC16F877A as a main controller, LM339 as sensor interface, UM3561 as a tone generator and ?PC2002 as a speaker driver (audio amplifier). LM7805, LM7812 and LM317 voltage regulators are used to obtain +5V, +12V and +3V respectively. Touch tone phone dialing interface. 5W High powerful audio alarm. 2 sensor interface with separate sensitivity adjustments. Programmed through the RS232 interface. Build-In intelligent light ON/OFF switch.

Security Alarm System (PIC16F877A)
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In this project we design low cost high performance programmable home security system using few LDR's as an input sensors. When above sensor(s) get triggered system may dial the user specified phone number (using build-in DTMF generator) and activate the high power audio alarm and lights. All the parameters of DTMF generator, audio alarm and light interface are programmed through the RS232 serial interface. Current firmware of this system presents interactive control system through the RS232 interface. This control system consist with the menu driven configuration options, self tests, system report generators, etc. DC Power input : Attach DC power supply with 18V - 25V (2A Max.) output. RS232 Connector : Connect RS232 serial cable to the port to configure the system. Do not use RS232 Null Modem cable with this port. PHONE/LINE connector : Attach standard RJ12/RJ11 telephone cable connector to this port. One port is need to use with the phone line and remaining port is for the phone (and it is optional). 3V LASER supply : 3V supply line for LASER diode assembly. Connectors for Sensor 1/2 : Attach high sensitive LDRs for these ports. To get the maximum sensitivity it is recommended to use EG&G VACTEC LDRs. Status Indicator : Indicate run, program and sensor trigger modes. Reset Switch : Press this button to reset entire alarm system. This button enable only when the audible alarm get activated. It is not...

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