Answers Database


How to analyze the delays for a specific path using M1 software?


Record #2742

Problem Title:
How to analyze the delays for a specific path using M1 software?


Problem Description:
Urgency: Standard

General Description:
How can I analyze any of the path delays between two pieces of
logic in my design?


Solution 1:



This capability is only available through the Timing Anaylyzer
graphical software.

    1. In the Design Manager, select the revision that you are
       analyzing.

    2. Click on the Timing Analyzer button in the Design Manager
       toolbox.

    3. If you are already in the Timing Analyzer and have setup
       some filters, select Path Filters -> Reset All Path Filters
       from the menu.

    4. To choose the starting points for your paths, select
       Path Filters->Path Analysis Filters->Select Sources... from
       the menu.

    5. In the Select Sources dialog choose the Selected Sources
       button. Choose the Source Element Type: Flip-Flops, Pads, Nets,
       Pins, CLBs, Clocks. Use the filter to limit the choices (wild
       card characters are valid). Move selected sources to the
       Selected Sources group box.

    6. To choose the ending points for your paths, select
       Path Filters->Path Analysis Filters->Select Destinations... from
       the menu.

    7. In the Select Destinations dialog choose the Selected Destionations
       button. Choose the Destination Element Type: Flip-Flops, Pads, Nets,
       Pins, CLBs, Clocks. Use the filter to limit the choices (wild
       card characters are valid). Move selected destinations to the
       Selected Destinations group box.

    8. To produce a timing report, select Analyze->Analyze All Paths from
       menu.

    9. The timing report will list all of the paths from worst case (top)
       to best case (bottom).

   10. If you only a few paths are reported, select Options->Report Options...
       from the menu. In the Report Options dialog, select a larger number
       for Maximum Paths per Timing Constraint. Then regenerate the report
       as in step 8.


Sample Report Below:

================================================================================
Timing constraint: PATH "PATHFILTERS" = FROM TIMEGRP "SOURCES" TO TIMEGRP
"DESTINATIONS" ;
 9909 items analyzed, 0 timing errors detected.
 Maximum delay is  71.159ns.
--------------------------------------------------------------------------------
Delay:	  71.159ns I0/NPD08 to I2/DAT<4>

Path I0/NPD08 to I2/DAT<4> contains 6 levels of logic:
Path starting from Comp: P85.PAD
To		     Delay type 	Delay(ns)  Physical Resource
						   Logical Resource(s)
-------------------------------------------------  --------
P85.I1		     Tpid		   1.180R  I0/NPD08
						   I0/NPD08
						   I0/NPDB08
CLB_R12C9.F2	     net		   7.971R  I0/NPDB08
CLB_R12C9.X	     Tilo		   1.300R  I2/N$2726//F
						   I2/N$2726//F
CLB_R15C9.F1	     net		   1.305R  I2/N$2726//F
CLB_R15C9.X	     Tilo		   1.300R  I2/CLCO//G
						   I2/CLCO//G
CLB_R19C7.F2	     net		   2.735R  I2/CLCO//G
CLB_R19C7.X	     Tilo		   1.300R  I2/NENBEXT//G
						   I2/NENBEXT//G
TBUF_R12C2.2.T	     net		  21.792R  I2/NENBEXT//G
TBUF_R12C2.2.O	     Ton		   0.800R  I2/TBUF_JH_2
P31.O net 26.416R I2/DATIN1<4>
P31.PAD Tops 5.060R I2/DAT<4>
                                  I2/DAT<4>.OUTBUF
                                  I2/DAT<4>
-------------------------------------------------
Total (15.4% logic, 84.6% route) 71.159ns

--------------------------------------------------------------------------------
Delay:	  68.708ns I0/NPD00 to I2/DAT<4>

Path I0/NPD00 to I2/DAT<4> contains 5 levels of logic:
Path starting from Comp: P27.PAD
To		     Delay type 	Delay(ns)  Physical Resource
						   Logical Resource(s)
-------------------------------------------------  --------
P27.I1		     Tpid		   1.180R  I0/NPD00
						   I0/NPD00
						   I0/NPDB00
CLB_R14C9.F4	     net		   6.560R  I0/NPDB00
CLB_R14C9.X	     Tilo		   1.300R  I2/N$1907//G
						   I2/N$1907//G
CLB_R19C7.F1	     net		   4.300R  I2/N$1907//G
CLB_R19C7.X	     Tilo		   1.300R  I2/NENBEXT//G
						   I2/NENBEXT//G
TBUF_R12C2.2.T	     net		  21.792R  I2/NENBEXT//G
TBUF_R12C2.2.O	     Ton		   0.800R  I2/TBUF_JH_2
P31.O net 26.416R I2/DATIN1<4>
P31.PAD Tops 5.060R I2/DAT<4>
                                  I2/DAT<4>.OUTBUF
                                  I2/DAT<4>
-------------------------------------------------
Total (14.0% logic, 86.0% route) 68.708ns


NOTE: The R on the delays refers to Rising.




End of Record #2742 - Last Modified: 09/30/97 14:50

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