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Altera_Forum's avatar
Altera_Forum
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11 years ago

Bidirectional pin

Hi :)

I've heard that integrating bidirectional pins for an FPGA device is expensive.

Is there any way that I would know how many inout pins supported for an FPGA chip?

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    What exactly do you mean by expensive? the pins on the chips all have IO buffers to allow bidirectional ports, and so are essentially "free".

    But you should never have bidirectional ports inside the logic of the FPGA as there are none inside the device, and so any in your code will be converted to muxes.
  • Altera_Forum's avatar
    Altera_Forum
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    I meant to build a bidirectional pin was expensive. I mistook the FPGA with a PIC or assemble chip :P

    Anyway, you made things clear for me now.

    Thanks Tricky :)