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Altera_Forum's avatar
Altera_Forum
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13 years ago

Accumulator in dsp builder

Hi i was wondering if there is an accumulator in the standard blockset of DSP Builder. if not, how do i make it?

thank you

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    13 years ago

    The Altera DSP Builder does not provide a accumulator. But you can easily build one with an adder and a register.

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

    There's a Multiply Accumulate block in the arithmetic library. You could wire the b input to a constant 1 so that it just does simple accumulation, but that might use up a DSP. It's possible that if you set "Use Dedicated Multiplier Circuitry" to NO, that Quartus might optimise away the multiply. You'd really have to see for yourself if that works.

    The other option would be to add a Pipelined adder, set its latency to one and feed its output into one of the inputs. Again this block is in the artithmetic library.