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Altera_Forum
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14 years ago

Ignored reserve pin compiler assignments

I got the following Quartus II V11.0 compiler warning messages for a Cyclone III with Active Serial Configuration with a Configuration Device via the basic Serial Flash Loader megafunction without shared ASMI interface. Unused pins are configured "As input tri-stated with weak pull-up". There is no external memory or other FPGA on the board.

Warning: Found Invalid Fitter assignments. See the Ignored Assignments panel in the Fitter Compilation Report for more information.

Warning: Ignored reserve pin assignment to SPI programming pin Data[0]

Warning: Ignored reserve pin assignment to SPI programming pin Data[1]/ASDO

Warning: Ignored reserve pin assignment to SPI programming pin DCLK

Warning: Ignored reserve pin assignments to SPI programming pin FLASH_nCE/nCSO

Someone has said these Warnings might be elevated to Critical Warnings, and the pins should be assigned as regular I/O to get rid of the warnings. I don't understand why.

(1) These are default assignments made automatically by the compiler. Why should it object? What is critical?

(2) The ignored values are "ON" for SDO, SCE, DCLK, Data[0]. There are no such assignments in the Assignment editor. The only assignments to these pins are Default Current Strength for SDO, SCE, DCLK (prefaced by "sfl:inst40|altserial_flash_loader:alt_serial_flash_loader_component|\GEN_ASMI_TYPE_1:asmi_inst~ALTERA_") assigned by the compiler.

(3) There is no assignment to Data[1]/ASDO in the Assignment Editor. Why is there a Warning?

(4) There is no SCE pin on the package. Why is there a Current Strength assignment in the Assignment Editor? I think the compiler assigned it.

(5) These pins are not used in user mode. They do not appear explicitly in the program. Should not DCLK, ASDO, nCSO be configured as outputs, dedicated programming pins, or compiler configured pins in user mode?

I am confused. Please clarify.

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    It sounds like it's picking up pin assignments for these in the QSF or perhaps the default_assignment file.

    If you post the qsf I'll look for it. I've never seen that warning unless I had a typo in my QSF where I accidentally assigned a pin on one of the configuration pins.

    Pete
  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    Here is the applicable part of the QSF file, plus a comment which I added and subsequently removed. I will send the rest if you really want all of it.

    I remembered that I had edited three assignments into the QSF file upon the recommendation of somebody at Altera. Here they are, preceded by the comment:

    # The next three lines are only needed so the compiler says there are no unassigned current strengths. Only DEFAULT is acceptable. What is the default current strength?

    set_instance_assignment -name CURRENT_STRENGTH_NEW DEFAULT -to "sfl:inst40|altserial_flash_loader:altserial_flash_loader_component|\\GEN_ASMI_TYPE_1:asmi_inst~ALTERA_DCLK"

    set_instance_assignment -name CURRENT_STRENGTH_NEW DEFAULT -to "sfl:inst40|altserial_flash_loader:altserial_flash_loader_component|\\GEN_ASMI_TYPE_1:asmi_inst~ALTERA_SCE"

    set_instance_assignment -name CURRENT_STRENGTH_NEW DEFAULT -to "sfl:inst40|altserial_flash_loader:altserial_flash_loader_component|\\GEN_ASMI_TYPE_1:asmi_inst~ALTERA_SDO"

    The SDC file has output delay assignments for DCLK, SCE, SDO; and an input delay assignment for DATA0. I think I put them there to stop TimeQuest from complaining but I am not certain.

    There are no package pins for SDO or SCE. The QDF files do not assign them. They are in the QSF file because I put them there.

    The QDF files assign ASDO "Use as regular IO" for several families (Cyclone II, Cyclone, Stratix II GX, Hardcopy II, Arria GX, Stratix II but not Cyclone III). The QSF file does not assign ASDO.

    The QDF files assign DATA0 and DATA1 "As input tri-stated". The QSF file does not assign them.
  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    I forgot to trace FLASH_nCE, nCSO, and DCLK:

    QDF files assign DCLK "Use as programming pin".

    QSF file only assigns DCLK Current Strength.

    QDF files assign FLASH_nCE and nCSO "As input tri-stated".

    QSF file does not assign FLASH_nCE or nCSO.