05-23-2019 08:19 AM
Facing timing violation issues I wanted to relax clock frequency generated by Clock Wizard.
But to my big surprise I failed to change output frequency in Clock Wizard settings: field Requested is greyed, means disable for editing.
Any comments ?
05-23-2019 10:43 AM
05-23-2019 11:32 AM
What does the report IP status say? Run the following command and check:
report_ip_status -name ip_status
Also make sure there are no background tasks running like synthesis or implementation run which will disable IP customization.
05-23-2019 11:49 PM
Report IP says that IP us up-to-date.
I've just started Vivado and opened the project. So, none process is supposed to run in background.
Then I opened the Clocking Wizard setup. The problem persists - I still can't modify output frequency of PLL
05-24-2019 12:03 AM
I've just found the option that blocks customizing of some options of Clock Wizard IP.
This option: Allow Override Mode on PLLE2 Settings tab, that was checked.
Once I unchecked it, customizing becames again possible.
05-24-2019 12:08 AM
I was too optimistic.
With Allow Override Mode unchecked I can change output frequency, it's true.
But when I reopen IP settings, I still see old value. Mystery !!!
05-24-2019 01:46 AM
The only method I found is to create new instance of Clock Wizard, setup all parameters, make connection then remove "freezed" instance
05-27-2019 06:50 AM
Here is approach that works:
Hint: without 4th step the new value isn't kept