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Altera_Forum
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17 years ago

Cyclone 3 problem: Holding nConfig low

I am having a really weird problem with a really simple board. Using an EP3C25E144C8N, active serial configuration mode with an EPCS16, MSEL[2:0] = 010. I can successfully erase and program the con...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
17 years ago

Did you electrically connect the exposed pad? Also, there may be a problem with non-monotonous rise of the 3.3V supply (drops after the 1.2 and 2.5V supply have reached their valid levels), see the respective comments in the device manual. If these points are O.K., nConfig may be simply shorted somewhere.