Halting PAR

Note: You are not able to halt PAR with Control-C as described below if you do not have Control-C set as the interrupt character. To set the interrupt character, enter stty intr ^V^C in the .login file or .cshrc file.

To halt a PAR operation, enter Control-C. In a few seconds, this message appears.

CNTRL-C interrupt detected.



Please choose one of the following options:

1. Continue processing and ignore the interrupt.

2. Normal program exit at next check point.

   This will result in saving the best results so far,

   after concluding current processing.

3. Exit program immediately.

4. Display Failing Timespec Summary.

5. Cancel the current job and move to the next one at

   the next check point.

Enter choice --> 

If you have no failing time specifications or are not using the -n option, Options 4 and 5 display as follows.

4. Display Failing Timespec Summary.

   (Not applicable: Data not available)

5. Cancel the current job and move to the next one at

   the next check point.

   (Not applicable: Not a multi-run job.)

You then select one of the five options shown on the screen. The options work in this way.

• Option 1 - this option causes PAR to continue operating as before the interruption. PAR then runs to completion.
  
  
• Option 2 - this option continues the current place/route iteration until one of the following “check points”.
  
  
  • After constructive placement
    
    
  • After the current optimization pass
    
    
  • After the current routing iteration
    
    The system then exits the PAR run and saves an intermediate output file containing the results up to the check point.
    
    If you use this option, you may continue the PAR operation at a later time. To do this, you must look in the PAR report file to find the point at which you interrupted the PAR run. You can then run PAR on the output NCD file produced by the interrupted run, setting command line options to continue the run from the point at which it was interrupted.
    
    Option 2 halt during routing may be helpful if you notice that the router is performing multiple passes without improvement, and it is obvious that the router will not achieve 100% completion. In this case, you may want to halt the operation before it ends and use the results to that point instead of waiting for PAR to end by itself.
    
    
• Option 3 - this option stops the PAR run immediately. You do not get any output file for the current place/route iteration. You do, however, still have output files for previously completed place/route iterations.
  
  
• Option 4 - PAR displays the contents of the ITR file on the screen and then resumes execution.
  
  
• Option 5 - Terminates current iteration if you have used the -n option and continues the next iteration.
  
  

  Note: If you started the PAR operation from the Design Manager as a background process on a workstation, you must bring the process to the foreground using the fg command before you can halt the PAR operation.

After you run PAR, you can use the FPGA Editor on the NCD file to examine and edit the results. You can also perform a static timing analysis using TRACE or the Timing Analyzer. When the design is routed to your satisfaction, you can input the resulting NCD file into the Xilinx Development System's BitGen program. BitGen creates files that are used for downloading the design configuration to the target FPGA. For details on BitGen, see the “BitGen” chapter.