An answering machine or automatic system is an electronic device that automatically responds to an incoming telephone call and plays a pre-recorded message and is able to record a message that the caller wishes to leave. These systems include a message recording system that has remote access to message playback, automatic dialing, alarm receiving equipment, automatic data entry systems and other common telephone devices used in conjunction with modem equipment. The microcontroller typically controls a series of peripherals, components of the answering machine, such as an LCD or LED display, an indicator light for recording and playback options, a DTMF receiver and an audio controller.
An answering machine must be capable of being remotely activated consisting of:
A switch that decides the mode of operation either automatic or normal.
Provision to receive calls automatically in automatic mode.
Provision for recording the message to be delivered to the incoming user and also to record their message
Storage for message
Microcontroller to deliver the control signal according to the mode of operation
The commonly used telephone answering devices comprise a number of features that allow the user to examine the presence of a call, capture calls, play recorded voice messages, record an announcement, and so on. Shooting a telephone answering machine made by counting the incoming bell signals AND when the count exceeds a predefined number set by the user. The machine is programmed in such a way that if the user does not reach his telephone within a specified period of time which is the function of the number of ring signals, the call is automatically answered and a message is again sent to the caller He to leave a message.
