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Altera_Forum
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14 years ago

CPLD I/O voltage for bidirectional pins

We are using Altera MAX V CPLD “5m160zt100c5n “in of our project. We are facing issues that when CPLD is not programming IO voltages on Bidirectional data lines are 3.3 V but when once CPL...
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Altera_Forum
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14 years ago

Do you check the voltage with a voltmeter or with an oscilloscope? If they are changing constantly, the measurement with a voltmeter could give you a bad value.

What else is connected on those pins?

Did you try a very simple design that just puts 1 on the output?