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    I want phase shift in DDS output depending upon the input

    I m using a DDS (Xilinx block) and i am gettin a sine wave with sample period of 0.001
    i have made the phase increment option in block parameter as register and im getting two new ports 'data' and 'we'

    ... so now i need to know how should i get a phase increment of pi radians ...what should be the input data type to the 'data'pin of DDS?

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    I want phase shift in DDS output depending upon the input

    Xilinx provides at least two different DDS cores. Which one are you using?

    The DATA phase input values range from 0 to almost 2*pi radians. For example, if your DATA is 16 bits wide, then values from 0 to 65536 represent 0 to 2*pi radians. You would input 32768 to get pi radians.



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  3. #3
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    I want phase shift in DDS output depending upon the input

    thnx very much echo ...

    i have system generator 7.1 and the model version of DDS is 1.4

    im making a M-aryPSK transceiver with transmitter havin ROM ... so my input to DDS will be from ROM

    how to calculate this value of 32768 for pi radians ?

    Added after 1 hours 14 minutes:

    ok ok i got the answer ... thnx echo.... i had not read it properly.... [:P]



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