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Altera_Forum's avatar
Altera_Forum
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13 years ago

VHDL Noob - creating one octave monophonic synthesizer

I am working on a project for school and was wondering how do you go about creating a sound frequency in VHDL? I am using quartus II

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  • Altera_Forum's avatar
    Altera_Forum
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    13 years ago

    What kind of signal do you want generate? I think DDS is the best technique for sound generation. See: www.fpga4fun.com

    You may create just a sinusoidal output, or a Fourier synthesis or an arbitrary waveform.
  • Altera_Forum's avatar
    Altera_Forum
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    13 years ago

    I'm not sure... this is the assignment:

    You are to design a keyboard which plays any note on a single octave. The user interface will consist

    of eight push buttons and a breadboard circuit that interfaces to the DE1. The DE1 will use the push

    buttons as keyboard keys and play the appropriate note frequency on the octave. The note should be

    audible using a piezo buzzer speaker. Frequencies are given by Table 1.
  • Altera_Forum's avatar
    Altera_Forum
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    13 years ago

    I made a synthesizer much like you're a trying to do. I used a PIC micro to read a 24 touch switches and send a byte to the FPGA and it generates a sinusoidal waveform ( with the proper frequency ) during 300ms. I make a ROM table with the senoidal values. This table is read with the DDS method ( phase addition ) and the music note determines the frequency of the waveform.