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Altera_Forum
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16 years ago

Cyclone III Initialization issue

Hi, I am using Cyclone III [EP3C16] on my custom built board. I programmed the device with a simple .sof file using Quartus II 9.0sp2 Web Edition via USB Blaster. I see the CONF_DONE pin high ...
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Altera_Forum
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16 years ago

Sounds like the FPGA looses it's configuration. One possible reason is either in NCONFIG driven low or a conflicting action of the on-chip configuration controller. The latter can happen, if e.g. an unconfigured AS device is connected to the FPGA. There's a Quartus programmer option to halt the on-chip configuration controller. Another possible reason is momentary drop of a power supply below the POR threshold.