From memory the data sheet discusses limiting the input current using a resistor. It then says that during configuration the PCI clamp diode is not in circuit so you need to make sure there are no 5V signals applied before the end of cunfiguration!
Pretty limiting, I always use IDT quickswitches to protect the FPGA pins from 5V inputs. They're simple, work well and cheap as chips (french fries).
Nial
------------------------------------------------ Nial Stewart Developments Ltd FPGA and High Speed Digital Design Cyclone Based 'Easy PCI' proto board
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