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Altera_Forum's avatar
Altera_Forum
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16 years ago

how to sample io pin using signaltap 2 logic analyzer?

using signaltap2 logic analyzer, when sample io pins , the waveform always low , but in fact , the pin is not always low .what is the matter?
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

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input pins and output pins are no problems. but bidirectional pins always low.

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Bidirectional pins are not generally inaccessible by SignalTap II. I often monitored complete data busses without a problem. But in some cases, SignalTap don't connect them, apparently depending on the way, the bidirectional pin is connected in the design. I didn't yet figure out a rule.