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Altera_Forum's avatar
Altera_Forum
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12 years ago

ALTSHIFT_TAPS Usage

Using the ALTSHIFT_TAPS with MLABS selected for the Cyclone V it looks like you get an output every three clocks since that is the minimum distance between taps. How about getting an output every clock AND without using a clock*3 for the ALTSHIFT_TAPS megafunction. Is there a way to get an output at every tap say by using some primitives along with the ALTSHIFT_TAPS. I don't want to clock it at 3 times the clock because now one has to be concerned with clock domains. Anyone know if it can be done?

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    12 years ago

    --- Quote Start ---

    Using the ALTSHIFT_TAPS with MLABS selected for the Cyclone V it looks like you get an output every three clocks since that is the minimum distance between taps. How about getting an output every clock AND without using a clock*3 for the ALTSHIFT_TAPS megafunction. Is there a way to get an output at every tap say by using some primitives along with the ALTSHIFT_TAPS. I don't want to clock it at 3 times the clock because now one has to be concerned with clock domains. Anyone know if it can be done?

    --- Quote End ---

    I don't think you can if the core does not support taps every stage.

    Multiply clock by 3 is not a problem if your clock is in phase and tied up to your system clock.
  • Altera_Forum's avatar
    Altera_Forum
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    12 years ago

    Rather than adhering to ALTSHIFT_TAPS, there are probably many ways to achieve what you want with a combination of internal RAM and registers. But what do you want to achieve exactly?