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Altera_Forum's avatar
Altera_Forum
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11 years ago

Tristate outputs - how to?

Hi, I want to tristate a group of outputs based on the state of an input pin (MAX7000S). I have found the TRI megafunction but it looks like this uses additional resources that shouldn't b...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
10 years ago

Answering my own question because Altera tech support does not exist. To create a tri-state output pin, connect the output of a TRI or TRI-BUF library part directly to the input of an output pin library part. The compiler will interpret this to mean you want a tri-state pin. The TRI control input is non-inverting - a high on the control enables the device output pin. A low on the control input puts the device pin in tri-state.

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