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Altera_Forum
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14 years ago

Unused CPLD Pins

I have two CPLDs on my PCB that connect to a common SPI bus. In order to keep things simple I'm trying to talk to only one of the chips at first but I'm having some trouble with the voltages which le...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

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If you're using a new CPLD, then the default setting should be as input. Did you change it?

Cheers,

Dave

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I did not change it, actually. Until recently, I didn't even know how to change it. In the compilation log I always noticed that Qaurtus was warning me that all unused pins were set to as outputs driving ground. Does this mean that they are basically an output set to low?