When we need to read some data from database usually we make a query and get data in text or other displayable format. But Achu wend different way. He designed an Interactive Voice Response System that simply dictates data over mobile phone.
This is how this works. Person who is accessing data makes a call to a predetermined phone number and then enters DTMF encoded request. As database is academic so student details, admission number, semester code, exam code etc. is required. Then query data from phone is sent to AVR microcontroller which communicates to PC via USB to serial converter. In computer a Python script makes an MySQL query which then is read with open source speech synthesizer (espeak). Sound routed to mobile phone so person hears data dictated. Sounds fun and its completely open source.
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