Quartus II Warning: Found pins functioning as undefined clocks

[Markus Jochim]

Hello,

I use Quartus II WebEdition 7.0 and have a simple design where the
signal mclk takes the role of the clock.


ENTITY Prescaler_50M_1 IS
PORT (
mclk: IN std_logic;
c1Hz: OUT std_logic
);
END Prescaler_50M_1;


The "Classic Timing Analyser Tool" complains:


Warning: Found pins functioning as undefined clocks and/or memory enables
Info: Assuming node "mclk" is an undefined clock


I looked this up in the Quartus II Handbook and found that it should
help to define "mclk" to be a base clock by either a Tcl command like:

create_base_clock -fmax 20ns -target mclk sys_clk

or by defining an absolute clock associated with node "mclk" by using
the GUI of Quartus II at the menu item "Assignments|Timing Analysis
Settings|Classig Timing Analyser Settings|Individual Clocks"


Unfortunately both ways do not work and the warning still appears.

Can someone help???

Best regards
Markus

 

[andybuonviri]

I had this same problem, and I went to the Classic Timing Analyzer
Settings tab, clicked Individual Clocks, and added a new entry. The
name is arbitrary (refclk in my case) but "Applies to Node" must be
set to the clock giving the warning. So I clicked on the List button,
found my clock pin in the list (CPLD_REFCLK), added it, and clicked
OK. When I recompiled the warning went away. Perhaps you weren't
selecting the same "mclk" node that was triggering the warning? Do you
have other instances of "mclk" in your design? Mine was an external
pin so maybe it's different, but I can verify that this method does
work in Web Edition 7.0.