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Altera_Forum
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15 years ago

cyclone III unused inputs

Folks, I'm working on a Cyclone III design with a BT.656 video input interface. The FPGA will be used in two products - one with the BT.656 circuitry populated and one without it populated. W...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

Thanks FvM.

I went ahead and assigned weak pullups on those pins, but apparently two of them do not support weak pullups so the build fails!

I'm trying to find some documentation on those pins to determine why they don't support pullups but I'm not finding any documents that get that specific.

The device is EP3C25F256A7and the failing pins are E1 and E2.

Pin Planner is showing them as dedicated clock pins, so perhaps that's why they don't support weak pullups?