This Voice Shield is particularly useful to activate the voice messages to the occurrence of an event in an alarm system, for a control I / O and generic for home automation, or to reproduce an alert when it is detected the approach of a person or a vehicle in a zone.
Based on chip ISD1790PY, this shield for Arduino, allows you to record and play up to 90 seconds of music and speech. The control with Arduino is easy thanks to a special library. The shield has several control buttons (REC, PLAY, FWD, ERASE, VOL, etc.), microphone capsule, a jack for audio input and a jack for audio output. Recording messages is done through the microphone and the audio input line IN can be used to record messages or music from an external source (MP3 players, mixers, etc.). The recording time is determined by the clock frequency of the internal oscillator; such frequency is defined with the value of the resistor R4 and in this case is 8 kHz.