This document describes a voice operated home appliance control system. The system uses a programmable speech recognition circuit that can be trained to recognize specific words or phrases in order to control electrical devices and appliances. A microcontroller interfaces with the speech recognition board and relays to control appliances based on voice commands. An LCD display provides status updates. The system is powered by a 5V regulated supply from a step-down transformer and rectifier circuit.

1. VOICE OPERATED HOME APPLIANCE CONTROL
ABSTRACT
Voice based industrial electrical appliances control is an interesting voice based project,
mainly useful for industrial applications, home automation. This project gives exact concept
of controlling a high voltage electrical device or DC / AC motor a voice instruction. This
project is the first step to design of voice based industrial automation projects.
The speech recognition system is easy to use programmable speech recognition circuit.
Programmable, in the sense that the system to be trained the words (or vocal utterances) the
user wants the circuit to recognize. This board allows us to experiment with many facets of
speech recognition technology. It has 8 bit data out which can be interfaced with any micro
controller. Some of interfacing applications which can be made are controlling home
appliances, robotics movements, Speech Assisted technologies, Speech to text translation,
and many more.
The 89C51 microcontroller contains four ports of each eight pins. In this project one port is
dedicated for speech recognition. Relays are interfaced through ULN driver circuit to control
the electrical appliances. A simple yet powerful program is written in assembly language and
burned into the microcontroller to record and accept voice instructions and to control the
devices. A 16 X 2 LCD with contrast control preset is provided for status display.
This project uses regulated 5V, 500mA power supply. 7805 three terminal voltage regulator
is used for voltage regulation. Bridge type full wave rectifier is used to rectify the ac output
of secondary of 230/12V step down transformer.

2. BLOCK DIAGRAM