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Altera_Forum
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15 years ago

Cyclone III and EPCS4

Hi, i am trying to start Cyclone III with EPSC4. I write VHDL code wich toggles one of FPGA pins, but nothing happens, Quartus is programming the flash device - programmer says that everything is ok,...
Altera_Forum's avatar
Altera_Forum
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15 years ago

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Is the exposed pad of the Cyclone III connected to ground?

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I also thought about this point, it's explicitely shown in the schematic. I wonder, if the pin is also known to be soldered correctly?

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at beginning system connects only 3.3V bus, when it is done CONF_DONE looks like in attachment, then 3.3V is off, and then all supplies are on togheter

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I'm not sure, what you are describing here. Is it about a irregular power-up sequence?

According to the hardware manual, schottky diode should be used as AS clamp diodes, I assume that the LED symbols have been used by mistake.