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FPGAOLOG's avatar
FPGAOLOG
Icon for Occasional Contributor rankOccasional Contributor
4 years ago
Solved

Is waitrequestAllowance suported for Altera EMIF external mem interface?

The Avalon document mentions waitrequestAllowance parameter but I cant see a way to set it in either Avalon mm bridge or EMIF Avalon interfaces. How can I set it to 1 for EMIF Avalon interface?
  • FPGAOLOG's avatar
    FPGAOLOG
    3 years ago

    " waitrequest will usually only be ...". There is no usually in RTL. There is always. So waitrequest may be asserted DURING the burst. This means everything connected to waitrequest must be combinatorial, and can't be pipelined.

    Thanks for the help. You may close this ticket.

sstrell's avatar
sstrell
Icon for Super Contributor rankSuper Contributor
4 years ago

Interface properties like that are usually for when you create a custom component that makes use of that property. It may or may not be available as a parameter for an off-the-shelf IP. If it's not in the parameter editor, it's not available for customization.

What are you trying to accomplish? Perhaps there's an alternate way to do it.

FPGAOLOG's avatar
FPGAOLOG
Icon for Occasional Contributor rankOccasional Contributor
4 years ago

I am trying to avoid combinatorial waitrequest signal handshaking between the ddr IP and the user logic .