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Altera_Forum's avatar
Altera_Forum
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17 years ago

Error & CONF DONE LED both glow when programming cyclone III fpga

Hi,

I m using Cyclone III EP3C120F780C7N FPGA in my project.

While programming FPGA using .sof file, Error LED glows for a moment & then after some time CONF DONE LED glows.

But when i see output on user LED, it seems that Program ( using simple counter) is working fine.

So please tell me , why Error LED glows for a moment before CONFIGURATION is DONE !!

whether there is mistake in programming methode ?

I m beginner in FPGA field, so experimenting with small program on Board to get familiar with QuartusII s/w & Board resources...

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    17 years ago

    Whenever you program your device, all outputs are floating thus all LEDs are "half on" (no matter if you drive oder sink with output pin in the design later on). Also applies to the time, the FPGA need to download it's data from a configuration device. At least that is what happens on my development boards with Cyclone II and III FPGAs that have LEDs connected.