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Altera_Forum
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8 years ago

JTAG Programming successfull but no effect at the ouput

I am using a Cyclone III EP3C120F484 device for my custom board. When I connect the USB Blaster and run the JTAG programmer in Quartus, the programming is done with no error. The code is just written to on/off the two LEDs. I have no PLLs or clocks involved yet to keep things simple. However, after the programming is done, I see no output on the pins. Everything is tied to 3.3V regardless of the configured program.

I have three voltage supplies for my FPGA: 1.2V for the core, which is okay, 2.5V for the JTAG and PLL, which are okay, and 3.3V for outputs on all banks, which look okay. I also checked the JTAG chain in Quartus which seemed okay.

I have checked the Conf_Done pin. This pin is high before programming and goes low after programming is done.Monitor the TDI and TDO pins. But i didn't reach the problem.

Can anyone help me with what could potentially be the problem?

6 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    CONF_DONE should be HIGH after programming. This is true when programming using any method. When in JTAG mode the programmer monitors the status of CONF_DONE through the JTAG port.

    Before and during programming, user I/O will be tri-stated and pulled up via internal pull-up resistors. So, if "Everything is tied to 3.3V" - and CONF_DONE is LOW, then your device is not programmed and you are looking at the internal pull-ups that are active on each I/O pin.

    Some other things to check:

    1) Is nCE tied to GND?

    2) Are both CONF_DONE & nSTATUS pulled up externally?

    Have you looked through the "configuration, design security, and remote system upgrades in the cyclone iii device family (https://www.altera.com/content/dam/altera-www/global/en_us/pdfs/literature/hb/cyc3/cyc3_ciii51016.pdf)" section of the handbook?

    Cheers,

    Alex
  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    Yes i have checked that nCE pin is tied to GND and both CONF_DONE & nSTATUS pins are pulled up externally. But didn't find any result yet.

    Mohsin
  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    1) Are all your power pins connected? Are they all at the correct voltages?

    2) Are all the MSEL pins connected directly to GND or VCCA?

    3) Is nCONFIG pulled up?

    4) Are you sure you're using the right programming file? You said the "programming is done with no error". However, I've never known the Quartus programmer to indicate everything is OK when the device hasn't actually been programmed. Can you check this again?

    Cheers,

    Alex
  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    Yes i have checked all Power pins and measure the voltages. Its seems ok.

    MSEL apins are durectly connected to GND and VCCA.

    nCONFIG pin is pulled up with 10K resistor and 3V3.

    I recheck the programming file but after all this analysis, fault not found yet.