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Altera_Forum's avatar
Altera_Forum
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15 years ago

Is there a maximum number of IO port for NIOS2/e ?

Hello,

I am working on quartus 9.1SP1, SOPCbuilders and SBT for eclipse.

Is there a maximum IO ports with NIOS2/e ?

because my design works with 14 IO ports and if i want to add one port in order to evolve my design, the design after programming .sof not working.

I don't understand.

Thank you for reply.

Vincent.

5 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    If you add too many Avalon slaves then your reduce fMax.

    But more likely you've done something stupid :-)
  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    There isn't a maximum, but if you add to many peripherals without pipelines it may become difficult to meet the timing requirements.

    Is your design properly constrained and does Timequest say it meets the timing requirements?
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    15 years ago

    Thank for replies,

    Actually I think its a Fmax problem or my design is not constrained correctly.

    I'am verifying my design : timequest and avalon MM bridges.

    Thank you.

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

    After checking my design (constrained timequest etc...) and read "user guide SOPC Builder" and "instantiating The Nios II Processor in SOPCBuilder" , I solved my problem.

    I think the AVALON pipeline bridges are not necessary for my design.

    We need every IO port is connected to the CPU instruction_master in SOPC_builder even if it takes a little more than the resources.

    My design work and the Fmax is the same.

    thank you for your ideas. :o

    Vincent.