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Altera_Forum
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16 years ago

m9k memory block reading in cyclone3

hi

i created ram with two ports (one read and one write) in cyclone3 using quartus. while reading data from ram ,read data is changing only at the end of address in simulation,ie 0 location data is appearing at 1st location,

please help me any one

with regards

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

    --- Quote Start ---

    reading data from ram ,read data is changing only at the end of address in simulation,ie 0 location data is appearing at 1st location

    --- Quote End ---

    This is normal as the address and data of the RAM blocks from the MegaWizard are registered by the clock. This means that there is a delay of one clock cycle before you see the result of a specific address during a read cycle.

    When you also add registers at the output, the delay will be two clock periods.