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Altera_Forum's avatar
Altera_Forum
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16 years ago

how can i simulate about the inout pin.

Why is QuartussII wave 'Z' for ever when I simulate one inout pin.i should how do it?

Wether the inout pin is support with the simulate tool in QuartussII?

3 Replies

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

    You need to think of 'Z' as '0' or '1'

    if the drive is '0' your wave should be '0'

    if the drive is '1' your wave should be '1'

    if there is no drive then the wave should be 'Z'

    if there is unknown drive then wave should be X

    for inout you need to drive the output when it is ouput...
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    16 years ago

    i know what you says.however,'0' or '1' drives it by output,output is 'z'.but its output is right when i use modesim .

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

    --- Quote Start ---

    Why is QuartussII wave 'Z' for ever when I simulate one inout pin.

    --- Quote End ---

    I don't understand the question. Inout or bidirectional is of course supported by the Quartus simulator. But which "wave" you are refering to? Quartus displays two signals, the input state and the the state driven to the output. What you see depends on

    - what you drive to the pin externally

    - if the output driver is enabled or disabled