During the synthesis process, Quartus reports "Ignoring invalid Fast-IO-Timing Assignments" which I am not able to discover, since Quartus does not say WHERE or WHICH assignment is set incorrectly. Any Idea ?
Exploring Quartus' Messages and Warnings
Sep 05, 2006
9 Replies
Did you try
- Double clicking on the message?
- Right click to pull up a menu that says 'Locate in..."?
Usually one of those two methods locates the source of the error. Don't recall if it works for the particular error message that you've posted though
KJ
I think there is also a section "ignored timing assignments" in the timing-report.
Thomas
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"alterauser" schrieb im Newsbeitrag news: snipped-for-privacy@d34g2000cwd.googlegroups.com...
@both:
Right-clicking and trying to locate it, brought no result, however. :-(
I know about the section "ignored timing reqs". - was empty in this case.
I would start a new project with a clean working directory and default assignments except for the file list.
Do:
Processing, Start, Analysis + Synthesis
Once that works start adding other assignments one at a time.
-- Mike Treseler
Hi Mike, yes of course I did that (in fact I partly disabled one contraints after another) - but I think it should be more convenient to be pointed directly to an errar, rather than doing research on this, since the next error like this will appear shortly most likely...
So, what did you find? Where was the error coming from?
If you can't find a workaround, call the "man"
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-- Mike Treseler
Are you sure that when you look at the assignments, in the assignament editor, that you don't have Fast Output/Input Enable Register enabled anywhere?
Description of Fast Output: Implements an output enable register in a cell that has a fast, direct connection to an I/O pin. If such a fast, direct connection to the I/O pin is not available in the I/O cell hardware, this option instructs the Fitter to lock the output enable register in the LAB adjacent to the I/O cell it is feeding.Turning on the Fast Output Enable Register option can help maximize I/O timing performance, for example, by permitting fast clock-to-output times. Turning this option off for a particular signal prevents the Fitter from implementing the signal automatically in an I/O cell or locking down the output enable register in the LAB adjacent to the I/O cell. This option is ignored if it is applied to anything other than a register or an output or bidirectional pin fed by a register.
Hello
I know what the e.g. "Fast IO" options do to the design and I have several of them constraining my ADC/DAC driving clocks as well as the input cells aquiring data from the ADCs and so on..
In the particlar case, it was a fast option of a DDR-cell.
But the question ist not how to find an error in THIS design, but how one can quickly locate an error in general.
As said, I found the misassignment by partly clicking on and off the options one ather the other, but this is not a fine way. Quartus should report this like "Assignment No 8 invalid", since the assignment ARE numbered.
Just an Idea ...
Typically the Ignored Timing Assignments in the Timing Analysis report section will give you details as to which signals are generating the warning. You can also right click on a signal within this report and choose Locate / Locate In Assignment Editor. I've never had any difficulty finding a signal that had a timing parameter which Quartus was ignoring.
alterauser wrote:
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