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Altera_Forum
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19 years ago

Cyclone III AS configuration bizarreness

I am using a cyclone III (EP3C25F324C8N) with an EPCS16 configuration device. I am programming the configuration device through the FPGA with the serial flash loader. The problem is that the Cyc...
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Altera_Forum
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18 years ago

This configuration thing is highly annoying - hard to do a confident design for mass-production with tight schedules while this is unresolved. I had exactly the same situation with the probe/screwdriver on CONF_DONE & shorting nSTATUS high. When adding a large cap (>1000uF) on the 3.3V line, then that will not work anymore either. This will also be influenced by the reference used for the pullups and MSEL's, since the behaviour completely changed when I changed the reference used for MSEL from VCCA to VCCIO (3.3V). Athough the errata sheet also makes mention of this, it still didn't really help regardless of tying to VCCIO or VCCA.