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could it be that this board is reconfigured by a watchdoch or a fpga pin ?
maybe you use a pin a bit different than the working sof.
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Yes...
Finally I found the solution for this problem:
quartus menu
assignments > device > device and pin options... > unused pins > Reserve all unused pins:
as input tri-stated (Before it was set to
as output driving ground.)
That is mentioned in the my first fpga tutorial:
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For Cyclone III devices, unused I/O pins default to tri-stated inputs. You can change this setting using the
unused pins tab in the
device and pin options dialog box. Refer to Quartus II Help for more information about this option and how to use it.
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This morning I already read that, but I thought that it was not important and I wanted to get on fast. Now I spent the whole day finding this simple error/bug. So we can see, that one should always work
unhurriedly.
So, thank you, MSchmitt! :)
Honored Contributor
