Description
When instantiating UART RS-232 IP, you may see the message below:
No Baud Rate validation because the clock rate is unknown
System Information doesn't match the requirement of IP. Double-click to open Info tab.
This warning message makes Qsys unable to generate and the generation process ends with errors.
Resolution
This issue might come when checking the Fixed baud rate option in UART RS-232 IP before connecting the clock signal of this IP.
To overcome this issue, please make sure to connect the clock port before you check the Fixed baud rate. If you already have this issue, open the UART RS-232 IP, then un-check the option, and check it back
This will be fixed in the future Quartus® Prime Software.