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Altera_Forum's avatar
Altera_Forum
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13 years ago

FPGA fried?

Hi,

I am using a cyclone iii on a custom board I made and I am trying to make sure the fpga section of the board is functional. When I program the fpga, I get the "100% successful" message from Quartus. However, when I test the output pins, they are all stuck at high regardless of my inputs. I was wondering if this means the chip is fried even though the JTAG function is working?

Best,

7 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    13 years ago

    If there is no smoke or smell then I would exclude that. try signaltap on few nodes.

  • Altera_Forum's avatar
    Altera_Forum
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    13 years ago

    I just checked and the nCE is tied to the ground on the board.

  • Altera_Forum's avatar
    Altera_Forum
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    13 years ago

    It might be worth checking the state of the nStatus and Config_Done pins after programming. Even though Quartus thinks everything is OK, something may still be amiss.

  • Altera_Forum's avatar
    Altera_Forum
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    13 years ago

    Right now, I am trying to use signal tap as kaz mentioned but I get an "Invalid JTAG configuration" message in the Instance Manager. I must add that I do not get any problems messages when I "scan JTAG chain". Is there some problem that the JTAG scanner is not picking up on?

  • Altera_Forum's avatar
    Altera_Forum
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    13 years ago

    Thanks gj_leeson.

    You were right, it was the "Config_done" pin. It was pulled up to 1.2V with a 1Kohm. I changed it to a 10K to 2.5V and now it's working.

    You guys were great help.