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Altera_Forum's avatar
Altera_Forum
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12 years ago

Radix 4 FFT implementation problem in vhdl

I am getting a problem with the operand and multiple driver while implementing radix 4 FFT.

the problem is that

g2(0) <= add(s(1),mult(s(5),w(1)));

g2(0) <= add(s(1),mult(s(9),w(2)));

g2(0) <= add(s(1),mult(s(13),w(3)));

from g2 actually there are three expressions arising...i am not able to use any operand in between them like and/or/+ so that i can avoid writing three times g2(0) which is nothing but problem of multiple driver.

the error is...and/or/+ cannot be any operand in such context like that(whatever operator i put there)....so what should i do plz help

Even though i have tried to convert those expressions in binary and then use the + operand in between but still the same problem persist....and even i tried with declaring function in the package with "and" but in either way also i was not able to solve the problem....so please help me

1 Reply

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

    please post the real code, and the real error. The code you posted shows a multiple driver error because you assignming g2(0) from 3 different sources. The rest of your post doesnt make a lot of sense.