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Delay Tune for beginner

binpersonal
Dear all, when I use manual delay tune in Allergo 16.3, why there are two numbers on the right hand side corner as the following figure?

Which number should I use?   And what are the meaning of  "total manhattan length" ?  Where I can find tutorials for dealy tune for 16.3?

  Net Name:            CH6
  Pin count:              4
  Via count:              3
  Total etch length:      13388.442 MIL
  Total manhattan length: 6524.945 MIL
  Percent manhattan:      205.19%

  No connections remaining

  Properties attached to net
    LOGICAL_PATH      = @mux_debug_brd.schematic1(sch_1):ch6
    NO_ROUTE
    ELECTRICAL_CONSTRAINT_SET  = CH0_U5

Electrical Constraints assigned to net
prop delay: from AD to AR  min=13400.000 MIL  max=13405.000 MIL

Thank You very much!
  • oldmouldy
    The figure didn't get attached correctly but I guess that is the "heads-up" display, the value will be the current delay, the "bar" will be red to the left, less than the "min" value, and red to the right, greater than the "max" value, and green in the middle to match. You are trying to tune the length to be between the two limits. At present, the length is 13388.442 mils which is below the "min" requirement of 13400 mils by about 12 mils. You can ignore the Manhattan Length for the purposes of delay tuning, this is just the orthogonal distance between the ends of the route (for example: North / South, then East / West to get from one pin to the other)
  • binpersonal

    Thanks,

     It displays " Dly -3161.751     +67.442"  when I use the "delay tune".

    Why the first value is negative? 

  • binpersonal

    Also my status bar is always red, it didn't turn green,  is there any setting I need to do to make it work?

    For example: when the status bar display "Dly -3508.416  +15.38", I got the etch length is 13001.38, with the range of my constraints,

    But the status bar didn't turn green, it is still red, and not in the middle either.  The two Dly values doesn't help me either. What should I do? 

    Thanks!

     
    LISTING: 1 element(s)

                  < NET >              

      Net Name:            CH34

      Pin count:              4
      Via count:              1
      Total etch length:      13001.38 MIL
      Total path length:      16103.443 MIL
      Total manhattan length: 4995.197 MIL
      Percent manhattan:      322.38%

      Pin                     Type      SigNoise Model        Location
      ---                     ----      --------------        --------
      U7.21                   UNSPEC                          (948.630 1193.701)
      U7.25                   UNSPEC                          (948.630 1170.079)
      T34.1                   UNSPEC                          (1193.063 -455.000)
      J1.24                   UNSPEC                          (617.500 -2981.500)

      1 unrouted connection(s) remaining
        T34.1 to J1.24

      Properties attached to net
        LOGICAL_PATH      = @mux_debug_brd.schematic1(sch_1):ch34
        NO_ROUTE
        ELECTRICAL_CONSTRAINT_SET  = CH2_U7

      Electrical Constraints assigned to net
        prop delay: from AD to AR  min=13000.000 MIL  max=13005.000 MIL

     

  • chads108

    It appears that you haven't finished routing the net in your last post.  I don;t think you can actually get the length of tye net to be within your specs if it is not completely routed.

  • binpersonal

    Thanks, for finished routing, the status bar doesn't turn green either, always red:

    Net Name:            CH6
      Pin count:              4
      Via count:              3
      Total etch length:      13388.442 MIL
      Total manhattan length: 6524.945 MIL
      Percent manhattan:      205.19%

      No connections remaining

      Properties attached to net
        LOGICAL_PATH      = @mux_debug_brd.schematic1(sch_1):ch6
        NO_ROUTE
        ELECTRICAL_CONSTRAINT_SET  = CH0_U5

      Electrical Constraints assigned to net
        prop delay: from AD to AR  min=13400.000 MIL  max=13405.000 MIL

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