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Command Reference    2.  Synopsys Commands             reset_path



NAME
          reset_path     Resets specified paths to single cycle
                         timing.

SYNTAX
          int reset_path [-setup | -hold] [-rise | -fall][-from
          from_list] [-to to_list]

          list from_list
          list to_list


ARGUMENTS
          -hold          Specifies that hold checking (minimum
                         delay) is reset to single cycle
                         behavior.


          -setup         Specifies that setup checking (maximum
                         delay) is reset to single cycle
                         behavior.


          -rise          Specifies that rising path delays are
                         reset to single cycle behavior.  The
                         default is that both rising and falling
                         delays are affected.


          -fall          Specifies that falling path delays are
                         set to single cycle behavior.  The
                         default is that both rising and falling
                         delays are affected.


          -from from_list
                         Specifies names of clocks, pins or cells
                         to use to find path startpoints.  If a
                         specified object is a clock, all flip-
                         flops, latches, and primary inputs
                         related to that clock are used as path
                         startpoints.


          -to to_list    Specifies names of clocks, pins or cells
                         to use to find path endpoints.  If a
                         specified object is a clock, all flip-
                         flops, latches, and primary outputs
                         related to that clock are used as path
                         endpoints.





V3.1      Synopsys Inc. 1988-1994. All rights reserved.       2-1



reset_path           2.  Synopsys Commands      Command Reference



DESCRIPTION
          Specifies that designated timing paths in the
          current_design are restored to the default single cycle
          behavior.  reset_path is used to undo the effect of
          set_multicycle_path, set_false_path, set_max_delay, and
          set_min_delay.  The attributes set by those commands
          are removed by reset_path.  Note that a general
          reset_path command will remove the effect of matching
          general or specific point-to-point exception commands.

          If -setup or -hold is not specified, both are restored
          to the default behavior.  The default is a setup
          relation of one cycle and a hold relation of zero
          cycles.  A hold value of zero means that hold is
          checked one active edge before the setup data at the
          destination register.

          If -setup is specified, only setup (maximum delay)
          checking is reset to the default behavior.

          If -hold is specified, only hold (minimum delay)
          checking is reset to the default behavior.

          There is separate setup and hold information for rise
          and fall.  In most cases, these will be reset together.
          -rise or -fall are used to reset only one or the other.

          To disable setup or hold calculations for paths, use
          set_false_path.

          To see the non-default path requirements on the design,
          use report_timing_requirements.


EXAMPLES
          The following example resets the timing relation
          between ff1/CP and ff2/D to the default single cycle.


                         dc_shell> reset_path -from { ff1/CP }
                         -to { ff2/D }


          This example resets rising delay to single cycle for
          all paths ending at latch2d.


                         dc_shell> reset_path -rise -to { latch2d
                         }






2-2       Synopsys Inc. 1988-1994. All rights reserved.      V3.1



Command Reference    2.  Synopsys Commands             reset_path



          This example shows how a specific and general point-
          to-point exception are set, and then removed.


                         dc_shell> set_false_path 2 -from A -to Z

                         dc_shell> set_max_delay 15 -to Z

                         dc_shell> reset_path -to Z /* removes
                         all exceptions to Z */



SEE ALSO
          current_design(2), find(2), report_constraint(2),
          report_timing_requirements(2), reset_design(2),
          set_false_path(2), set_max_delay(2), set_min_delay(2),
          set_multicycle_path(2).





































V3.1      Synopsys Inc. 1988-1994. All rights reserved.       2-3

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