Cellphone Operated Home Automation System

Dial your number using DTMF phone or Cell phone from anywhere in the world and remotely turn on/off any of the 8 relays. The MCU on the interface senses Telephone ring, Automatic telephone pick up, and line hang up, displays information on a 16x2 LCD module and controls the relay switching. This interface uses the popular MT8870 DTMF decoder IC along with AT89S51 Microcontroller. The HOME AUTOMATION SYSTEM is connected to cell phone using enhancement. The caller has to dial the cell phone number. After two or three rings the cell phone picks up call. Then he has to enter the six-digit password. After the successfully entering of password the relay will be activated. When the password has been incorrectly entered four times in a row, the interface an error sound is produced and the receiver replaced on-hook this function thwarts any attempt by 'hackers' to quickly try a large number of codes in a sequence.