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Altera_Forum
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14 years ago

Bidirectional buffer

Hi, I am working on Altera FPGA. Please help me to code a Bidirectional bus using HDL. Can anyone share a code for this. Regards, freak
Altera_Forum's avatar
Altera_Forum
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12 years ago

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In any case the real signal always falls into a specific state, low or high.

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Not necessarily. A floating pin without pull/up, pull-down or hold circuit might also arbitrarily oscillate between '1' and '0'. 'X' in simulation can be understood as reflecting this unknown state.

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there is not a 'tristate' level.

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That's the essential point. 'Z' can't be detected as an input state.