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Altera_Forum's avatar
Altera_Forum
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16 years ago

DE2 Echo Feature

Hello,

I am working with a DE2 trying to add an echo feature which would take the sound input, add an echo, and send the result to the output. I am having trouble with this, and was wondering if anyone could help me out with suggestions for how to do this.

I am new to the DE2, so please try to keep any ideas in basic terms.

Thanks!

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    Hi,

    You can configure the audio codec chip's register such that line input directly routed to line output.

    Regards,

    Hardik Sheth
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    Hello,

    Thank you for your reply. I actually am having trouble with adding the echo prior to output. Do you have any ideas on that?

    Thanks!
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    Hi, you need to create some sort of RAM memory, i just ordered DE2 board so I can't help with it yet. but on my spartan 3an i did it that way : created single block memory of about 16k addreses(remember, read first write later) , 14 bit width (ADC on spartan board is just 14 bit, DAC - 12 bit), and then in each clk cycle i did this : 

    
dina <= input(13 downto 0) + ( '0' & douta(13 downto 1) );
addra <= addra + 1;
output <= dina(13 downto 2);
-- addra is addres of RAM row
-- dina is input port of RAM (14 bits)
-- douta is output from RAM
-- input is signal from ADC (14 bit)
-- output is data do DAC (12 bit)
-- input is mixed with RAM data divided by two (to silence echo part)
-- and sended to DAC

    Echo works amazingly good, even on ADC\DAC not created for audio processing :)

    Any question more, just ask :) When Terasic will send me my DE2 i'll post here more often :) :)