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Altera_Forum's avatar
Altera_Forum
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16 years ago

Can Altera's sync_FIFO or async_FIFO be dead?

Hi,

There is a sync_FIFO or async_FIFO in a design. If we write data into it when it's full or read data from it when it's empty, is there any chance that the FIFO will be dead? I mean, in this case, we could not write any data into it no matter it is full or not, or we could not read correct data from it any more.

If the FIFO is turely dead, we could make it alive again except power-off-and-on? Can a positive pulse on asynchronous clear be useful?

Do we have any means to avoid this phenomenon?

Best Regards

2 Replies

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

    It won't be "dead", but can become corrupted. In that case a clear will reset the state of the FIFO.

    There are some safe functions that can be enabled in the megawizard (and I think they are enabled by default). With those options the FIFO won't become corrupted if you try to write to it when it's full or read when it is empty. The action will just be ignored by the FIFO.