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Altera_Forum's avatar
Altera_Forum
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14 years ago

QuartusII: Invalid assignment for clock

solved

the problem was to leave a space between '10' and '[' :

create_clock -period 10 [get_ports ref_clk_i]

*****************************************************

Hi all,

before TimeQuest Analysis, i was setting clock_port named "ref_clk_i" to a signal of 100MHz:

create_clock -period 10[get_ports ref_clk_i]

but appears this error:

warning: invalid assignment for clock: the option -name has the following error: could not identify a name for this clock. clock was not created or updated.

Where am I going wrong?

7 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    create_clock -period 10 -name ref_clk [get_ports ref_clk_i]

    When you get errors like that, type "create_clock -long_help" in TimeQuest and it usually becomes apparent.
  • Altera_Forum's avatar
    Altera_Forum
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    thanks for your answer, but now I've another problem :)

    in the same project, I have 2 clocks in input: 'ref_clk_i' and 'clock_i'.

    I set up these clocks with tickle commands

    create_clock -period 10 -name ref_clk_i [get_ports ref_clk_i]

    create_clock -period 1 -name clk_i [get_ports clk_i]

    and after that I clicked 'Update the timing netlist', but this is the warning message I received:

    warning: the following clock transfers have no clock uncertainty assignment

    warning: from ref_clk_i (rise) to ref_clk_i (rise) (setup and hold)

    warning: from clk_i (rise) to ref_clk_i (rise) (setup and hold)

    warning: from clk_i (fall) to ref_clk_i (rise) (setup and hold)

    Where am I going wrong?
  • Altera_Forum's avatar
    Altera_Forum
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    you're right, in fact, here's the message I received:

    tcl>set_clock_uncertainty

    missing required positional argument: <uncertainty>

    ---------------------------------------------------------------------------

    usage: set_clock_uncertainty [-h | -help] [-long_help] [-add] [-fall_from <fall_from_clock>] [-fall_to <fall_to_clock>] [-from <from_clock>] [-hold] [-rise_from <rise_from_clock>] [-rise_to <rise_to_clock>] [-setup] [-to <to_clock>] <uncertainty>

    -h | -help: short help

    -long_help: long help with examples and possible return values

    -add: specifies that this assignment is an addition to the clock uncertainty derived by derive_clock_uncertainty call

    -fall_from <fall_from_clock>: valid destinations (string patterns are matched using tcl string matching)

    -fall_to <fall_to_clock>: valid destinations (string patterns are matched using tcl string matching)

    -from <from_clock>: valid destinations (string patterns are matched using tcl string matching)

    -hold: specifies the uncertainty value (applies to clock hold or removal checks)

    -rise_from <rise_from_clock>: valid destinations (string patterns are matched using tcl string matching)

    -rise_to <rise_to_clock>: valid destinations (string patterns are matched using tcl string matching)

    -setup: specifies the uncertainty value (applies to clock setup or recovery checks) (default)

    -to <to_clock>: valid destinations (string patterns are matched using tcl string matching)

    <uncertainty>: uncertainty

    I surely have to add something
  • Altera_Forum's avatar
    Altera_Forum
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    Sorry, I typed it wrong. Use:

    derive_clock_uncertainty

    That will auto-calculate all the uncertainties between clocks. No need for set_clock_uncertainty.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    ok, in fact here's the message:

    tcl> derive_clock_uncertainty

    Info: Clock uncertainty calculation is delayed until the next update_timing_netlist call.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    I've created the .sdc file and I've added it to the project;

    I restarted the compilation and I noticed that the number of warnings is decreased, but however remains this:

    warning: the following clock transfers have no clock uncertainty assignment

    warning: from ref_clk_i (rise) to ref_clk_i (rise) (setup and hold)

    and I don't know why.

    Can you help me?