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Altera_Forum's avatar
Altera_Forum
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16 years ago

no bidirectional PIO on Stratix III?

Hi,

I'm trying to implement the graphics display that comes with the stratix iii (DSP) dev. kit. Because there's no special core for this 128x64 b/w display I want to use a pio with bidirectional pins (to be able to read the busy flag), but the SOPC builder doesn't offer this option.

When I switch to a Cyclone III device the option is available.

Anybody got an idea if this is a bug or a feature:confused:

btw. I'm using Quartus II 8.1 (and don't want to change version during project)

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    Im not familiar to SOPC builder stuff, but I guess the problem may come from a pin definition as out rather than inout in the design?

  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    thanks for the response especially because it's sunday!

    I'm afraid I don't know exactly what you mean. By the time I configure the PIO core in the SPOC builder the configuration of the FPGA pins isn't made yet. This usually happens where the SOPC design is instantiated.

    The strange thing is when I switch the FPGA family from Stratix III to Cyclone III in the SOPC builder the "bidirectional" option for the PIO ist there otherwise not.

    Is there a difference between the Stratix III pins and the Cyclone III pins I'm too blind to see?
  • Altera_Forum's avatar
    Altera_Forum
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    16 years ago

    I was referring to the port setting in the design top, that isn't set necessarily by the SOPC builder. But your report sounds like it's a different issue. Stratix III has I/O cells similar to other FPGA families, thus I don't see a basic difference. But I fear, I can't help in this regard.