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Altera_Forum's avatar
Altera_Forum
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8 years ago

[SDC] Input/Output delay for All ports -> script writing

Hi All,

How can I create the timing constraints (set_input/output_delay) for all ports (excepting clocks and reset ports)?

Let's say the design has the following clocks: clk0, clk1, clk2 and following resets: rstn0, rstn1, rstn2 and hundreds of other ports.

How can I write a script, which set input delays of 0ns for all input ports (excepting clk0, clk1, clk2, rstn0, rstn1, rstn2) and output delays of 0ns for all output ports?

Thank you!

25 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    I don't quite understand what you want to accomplish here. Your input and output delays could be 0 for a *minimum* delay, but you also need a matching *maximum* delay. The range of delay is required to give the Fitter an idea of what it has to work with as to the placement of the input or output register.

    set_input_delay -clock <virtual clock that drives upstream device> -max [get_ports in*] <max external delay based on tco of upstream device and board delays>

    set_input_delay -clock <virtual clock that drives upstream device> -min [get_ports in*] 0

    set_output_delay -clock <virtual clock that drives downstream device> -max [get_ports out*] <max external delay based on tsu of downstream device and board delays>

    set_output_delay -clock <virtual clock that drives downstream device> -min [get_ports out*] 0
  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    Does the [get_ports out*] list all the output ports and [get_ports in*] list all the input ports?

    How can I exclude certain ports from these listings?

    Is it possible to work with collections here?

    How to remove the input/output delay constraints from the certain ports?

    Thank you!
  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    When I run the get_ports out* command from Quartus console, I'm receiving the following errors? 

    
Error:ERROR: Quartus Prime Tcl command "get_ports" is only available for use in the following executables:
Error:    quartus_fit
Error:    quartus_sta
Error:    while executing
Error:    get_ports out*

    Why? How to fix?
  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    I used in* and out* as examples. You have to put in your own port names.

  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    this is exactly what I asked for :-) how to list ALL input ports without listing each port separately!

    How can I make a collection (list) of ALL the input ports (something like 'create_collection all_inputs')?
  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    running the all_inputs command gives the same result: 

    Error:ERROR: Quartus Prime Tcl command "all_inputs" is only available for use in the following executables:
Error:	quartus_fit
Error:	quartus_sta
Error:    while executing
Error:"all_inputs"

    So, what's the solution?
  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    It's very simple - just several lines... 

    set_time_format -unit ns -decimal_places 3
create_clock -name {clk}       -period 10.000 -waveform { 0.000 5.000 } 
create_clock -name {fifo_rclk} -period 10.000 -waveform { 0.000 5.000 } 
set_input_delay -clock { clk } 5 
set_output_delay -clock { clk } 5
  • Altera_Forum's avatar
    Altera_Forum
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    8 years ago

    Use something like:

    set data_inputs [all_inputs]

    set data_inputs [remove_from_collection [all_inputs] clk]

    That will create a list without clock. If you want to remove something else, do another line:

    set data_inputs [remove_from_collection $data_inputs reset]

    Repeat as necessary. If you want to visually see what's in it, then do:

    query_collection -all -report $data_inputs

    Once correct, use in constraint:

    set_input_delay -clock clk -max 0.0 $data_inputs

    Then repeat for outputs