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  3. Inputs without external driver/transition

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Inputs without external driver/transition

Kabal
Kabal over 11 years ago

Here is how I defined constraints for example for my inputs:

 # set input ports transition slew rates

set_input_transition -rise -min 0.5 /designs/refleks_switcher/ports_in/pwm_in_port1*

set_input_transition -fall -min 0.5 /designs/refleks_switcher/ports_in/pwm_in_port1*


# set external driver input slew (in picoseconds)

set_attribute external_driver_input_slew {100 100} /designs/refleks_switcher/ports_in/pwm_in_port1*

However, when I run:

report timing -lint

it still shows the same amount of ports with "inputs without external driver/transistion" warning,

why is RTL Compiler not happy with the constraints I defined? I did define the transition 

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  • Kabal
    Kabal over 11 years ago
    ok nevermind I had to use external_driver attribute and I made one of the BUFFERS from library to pretend driving my input pins of top module.
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  • Kabal
    Kabal over 11 years ago
    ok nevermind I had to use external_driver attribute and I made one of the BUFFERS from library to pretend driving my input pins of top module.
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  • asif123
    asif123 over 3 years ago in reply to Kabal

    could you elaborate on how you did it with an example since iam facing the exact issue.

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