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Altera_Forum's avatar
Altera_Forum
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15 years ago

Timing issue

Hi,

How do I know how match conditions I can put inside the "if (conditions) then" without causing any timing issue (missing clocks...)? Can I write: "if (a='1' and b='0' and…… z='1') then idan<='1';"? maybe something to do to Fmax …

Thanks, Idan

1 Reply

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

    I commonly use this construct to test for saturation:

    clocked process...

    if signed(data) < 32768 and signed(data > -32768 then...

    with data about 18 or 20 bits thus the test involves 40 bits comparator.

    I don't see any timing problem. But data is registered before the if test.

    So as long as your inputs to the if test are registered and result is registered then hope it will not be a burden on timing.