# Parallax STA documentation

James Cherry
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2025-03-17T12:59:52.463870538
2010-07-31T21:07:00
2026-06-27T19:17:53.216896000
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OpenSTA

Table of Contents

Table of Contents

Command Line Arguments1

Example Command Scripts1

Timing Analysis using SDF2

Timing Analysis with Multiple Process Corners2

Timing Analysis with Multiple Corners and Modes3

Power Analysis3

TCL Interpreter5

Debugging Timing6

No paths found6

No path reported an endpoint7

Commands7

Filter Expressions84

Variables85

Command Line Arguments

The command line arguments for sta are shown below.

sta -help show help and exit -version show version and exit -no_init do not read ~/.sta -no_splash do not print the splash message -threads count|max use count threads -exit exit after reading cmd_file cmd_file source cmd_file

When OpenSTA starts up, commands are first read from the user initialization file ~/.sta if it exists. If a TCL command file cmd_file is specified on the command line, commands are read from the file and executed before entering an interactive TCL command interpreter. If -exit is specified the application exits after reading cmd_file. Use the TCL exit command to exit the application. The –threads option specifies how many parallel threads to use. Use –threads max to use one thread per processor.

Example Command Scripts

To read a design into OpenSTA use the read_liberty command to read Liberty library files. Next, read hierarchical structural Verilog files with the read_verilog command. The link_design command links the Verilog to the Liberty timing cells. Any number of Liberty and Verilog files can be read before linking the design.

Delays used for timing analysis are calculated using the Liberty timing models. If no parasitics are read only the pin capacitances of the timing models are used in delay calculation. Use the read_spef command to read parasitics from an extractor, or read_sdf to use delays calculated by an external delay calculator.

Timing constraints can be entered as TCL commands or read using the read_sdc command.

The units used by OpenSTA for all command arguments and reports are taken from the first Liberty file that is read. Use the set_cmd_units command to override the default units. Use the report_units command to see the ccmmand units.

Timing Analysis using SDF

A sample command file that reads a library and a Verilog netlist and reports timing checks is shown below.

read_liberty example1_slow.libread_verilog example1.vlink_design topread_sdf example1.sdfcreate_clock -name clk -period 10 {clk1 clk2 clk3}set_input_delay -clock clk 0 {in1 in2}report_checks

This example can be found in examples/sdf_delays.tcl.

Timing Analysis with Multiple Process Corners

An example command script using three process corners and +/-10% min/max derating is shown below.

read_liberty nangate45_slow.lib.gzread_liberty nangate45_typ.lib.gzread_liberty nangate45_fast.lib.gzread_verilog example1.link_design topset_timing_derate -early 0.9set_timing_derate -late 1.1create_clock -name clk -period 10 {clk1 clk2 clk3}set_input_delay -clock clk 0 {in1 in2}define_scene ss -liberty nangate45_slowdefine_scene tt -liberty nangate45_typdefine_scene ff -liberty nangate45_fast# report all scenesreport_checks -path_delay min_max# report typical scenereport_checks -scene tt

This example can be found in examples/multi_corner.tcl. Other examples can be found in the examples directory.

Timing Analysis with Multiple Corners and Mode s

OpenSTA supports multi-corner, multi-mode analysis. Each corner/mode combination is called a “scene”. The SDC constraints in each mode describe a different operating mode, such as mission mode or scan mode. Each corner has min/max Liberty libraries and SPEF parasitics.

A mode named “default” is initially created for SDC commands. It is deleted when a mode is defined with set_mode or read_sdc -mode. Similartly, a named “default” is initially created that is deleted when define_scene is used to define a scene.

An example command script using two process corners two modes is shown below.

read_liberty asap7_small_ff.lib.gzread_liberty asap7_small_ss.lib.gzread_verilog reg1_asap7.vlink_design topread_sdc -mode mode1 mcmm2_mode1.sdcread_sdc -mode mode2 mcmm2_mode2.sdcread_spef -name reg1_ff reg1_asap7.spefread_spef -name reg1_ss reg1_asap7_ss.spefdefine_scene scene1 -mode mode1 -liberty asap7_small_ff -spef reg1_ffdefine_scene scene2 -mode mode2 -liberty asap7_small_ss -spef reg1_ssreport_checks -scenes scene1report_checks -scenes scene2report_checks -group_path_count 4

This example can be found in examples/mcmm3.tcl.In the example show above the SDC for each mode is in defined in a separate file. Alternatively, the SDC can be defined in the command file using the set_mode command between SDC command groups.

set_mode mode1create_clock -name m1_clk -period 1000 {clk1 clk2 clk3}set_input_delay -clock m1_clk 100 {in1 in2}set_mode mode2create_clock -name m2_clk -period 500 {clk1 clk3}set_output_delay -clock m2_clk 100 out

Statistical Timing Analysis

OpenSTA also supports statistical timing analysis with Liberty Variation Format (LVF) libraries. Statistical timing uses a probability distribution to represent a delay or slew rather than a single number.

Normal and skew normal probability distributions are supported. SSTA is enabled with the sta_pocv_mode variable.

set sta_pocv_mode scalar|normal|skew_normal scalar mode is for non-SSTA analysisnormal mode uses gaussian normal distributionsskew_normal mode is for skew normal LVF moment based distributions

The target quantile of a delay probability distribution (confidence level) is set with the sta_pocv_quantile variable.

set sta_pocv_quantile <float>

The default value is 3 standard deviations, or sigma.

Use the variation field with the report_checks and report_check_types commands to see distribution parameters in timing reports.

A command file for analyzing a design with statistical timing is shown below.

read_liberty lvf_library.lib.gzread_verilog design.vlink_design topcreate_clock -period 50 clkset_input_delay -clock clk 1 {in1 in2}set sta_pocv_mode skew_normalreport_checks -fields {slew variation input_pin} -digits 3

Startpoint: r2 (rising edge-triggered flip-flop clocked by clk)Endpoint: r3 (rising edge-triggered flip-flop clocked by clk)Path Group: clkPath Type: max Slew Delay Variation Time Description--------------------------------------------------------------------------- 0.000 0.000 0.000 clock clk (rise edge) 0.000 0.000 clock network delay (ideal) 0.000 0.000 0.000 ^ r2/CK (FDPQ1) 12.026 mean 0.017 mean_shift 0.366 std_dev 0.000 skewness 4.648 12.409 12.409 v r2/Q (FFQ1) 4.648 0.000 12.409 v u1/A (BUF1) 6.084 mean 0.007 mean_shift 0.188 std_dev 0.000 skewness 2.513 6.137 18.546 v u1/X (BUF1) 2.513 0.000 18.546 v u2/A2 (AN21) 6.447 mean 0.008 mean_shift 0.191 std_dev 0.000 skewness 2.565 6.497 25.043 v u2/X (AN21) 2.565 0.000 25.043 v r3/D (FFQ1) 25.043 data arrival time 0.000 50.000 50.000 clock clk (rise edge) 0.000 50.000 clock network delay (ideal) 0.000 50.000 clock reconvergence pessimism 50.000 ^ r3/CK (FFQ1) -9.376 40.624 library setup time 40.624 data required time--------------------------------------------------------------------------- 40.624 data required time -25.043 data arrival time--------------------------------------------------------------------------- 15.581 slack (MET)

The standard deviation for normal distributions is specified with the following liberty timing groups.

ocv_sigma_cell_riseocv_sigma_cell_fallocv_sigma_rise_transitionocv_sigma_fall_transitionocv_sigma_rise_constraintocv_sigma_fall_constraint

LVF skew normal distributions are specified with liberty groups below.

ocv_std_dev_cell_riseocv_std_dev_cell_fallocv_mean_shift_cell_riseocv_mean_shift_cell_fallocv_skewness_cell_riseocv_skewness_cell_fallocv_std_dev_rise_transitionocv_std_dev_fall_transitionocv_skewness_rise_transition ocv_skewness_fall_transitionocv_mean_shift_rise_transitionocv_mean_shift_fall_transitionocv_std_dev_rise_constraintocv_std_dev_fall_constraintocv_skewness_rise_constraintocv_skewness_fall_constraintocv_mean_shift_rise_constraintocv_mean_shift_fall_constraint

Power Analysis

OpenSTA also supports static power analysis with the report_power command. Probabalistic switching activities are propagated from the input ports to determine switching activities for internal pins.

read_liberty sky130hd_tt.libread_verilog gcd_sky130hd.vlink_design gcdread_sdc gcd_sky130hd.sdcread_spef gcd_sky130hd.spefset_power_activity -input -activity 0.1set_power_activity -input_port reset -activity 0report_power

In this example the activity for all inputs is set to 0.1, and then the activity for the reset signal is set to zero because it does not switch during steady state operation.

Group Internal Switching Leakage Total Power Power Power Power (Watts)----------------------------------------------------------------Sequential 3.27e-04 7.87e-05 2.96e-10 4.06e-04 36.4%Combinational 2.34e-04 3.10e-04 6.95e-10 5.43e-04 48.7%Clock 4.68e-05 1.20e-04 2.30e-11 1.67e-04 15.0%Macro 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.0%Pad 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.0%----------------------------------------------------------------Total 6.07e-04 5.09e-04 1.01e-09 1.12e-03 100.0% 54.4% 45.6% 0.0%

This example can be found in examples/power.tcl.

Gate level simulation results can be used to get a more accurate power estimate. For example, the Icarus verilog simulator can be used to run the the test bench examples/gcd_tb.v for the gcd design in the previous example.

iverilog -o gcd_tb gcd_tb.vvvp gcd_tb

The test bench writes the VCD (Value Change Data) file gcd_sky130hd.vcd which can then be read with the read_vcd command.

read_liberty sky130hd_tt.libread_verilog gcd_sky130hd.vlink_design gcdread_sdc gcd_sky130hd.sdcread_spef gcd_sky130hd.spefread_vcd -scope gcd_tb/gcd1 gcd_sky130hd.vcd.gzreport_power

This example can be found in examples/power_vcd.tcl.

Note that in this simple example design simulation based activities does not significantly change the results.

TCL Interpreter

Keyword arguments to commands may be abbreviated. For example,

report_checks -unique

is equivalent to the following command.

report_checks -unique_paths_to_endpoint

The help command lists matching commands and their arguments.

> help report*report_annotated_check [-setup] [-hold] [-recovery] [-removal] [-nochange] [-width] [-period] [-max_skew] [-max_lines liness] [-list_annotated]group_path_count [-list_not_annotated] [-constant_arcs]report_annotated_delay [-cell] [-net] [-from_in_ports] [-to_out_ports] [-max_lines liness] [-list_annotated] [-list_not_annotated] [-constant_arcs]report_arrival pinreport_check_types [-violators] [-verbose] [-scene scene] [-format slack_only|end] [-max_delay] [-min_delay] [-recovery] [-removal] [-clock_gating_setup] [-clock_gating_hold] [-max_slew] [-min_slew] [-max_fanout] [-min_fanout] [-max_capacitance] [-min_capacitance [-min_pulse_width] [-min_period] [-max_skew] [-net net] [-digits digits [-no_line_splits] [> filename] [>> filename]report_checks [-from from_list|-rise_from from_list|-fall_from from_list] [-through through_list|-rise_through through_list|-fall_through through_list] [-to to_list|-rise_to to_list|-fall_to to_list] [-unconstrained] [-path_delay min|min_rise|min_fall|max|max_rise|max_fall|min_max] [-scene scene] [-group_path_count path_count] [-endpoint_path_count path_count] [-unique_paths_to_endpoint] [-slack_max slack_max] [-slack_min slack_min] [-sort_by_slack] [-path_group group_name] [-format full|full_clock|full_clock_expanded|short|end|summary]...

Many reporting commands support redirection of the output to a file much like a Unix shell.

report_checks -to out1 > path.logreport_checks -to out2 >> path.log

Debugging Timing

Here are some guidelines for debugging your design if static timing does not report any paths, or does not report the expected paths.

Debugging timing problems generally involves using the following commands to follow the propagation of arrival times from a known arrival downstream to understand why the arrival times are not propagating:

report_edgesreport_arrivalsreport_net

report_edges -from can be used to walk forward and report_edges -to to walk backward in the netlist/timing graph. report_arrivals shows the min/max rise/fall arrival times with respect to each clock that has a path to the pin. report_net shows connections to a net across hierarchy levels.

No paths found

The report_checks command only reports paths that are constrained by timing checks or SDC commands such as set_output_delay. If the design has only combinational logic (no registers or latches), there are no timing checks, so no paths are reported. Use the -unconstrained option to report_checks to see unconstrained paths.

% report_checks -unconstrained

If the design is sequential (has registers or latches) and no paths are reported, it is likely that there is a problem with the clock propagation. Check the timing at an register in the design with the report_arrivals command.

% report_arrivals r1/CP (clk ^) r 0.00:0.00 f INF:-INF (clk v) r INF:-INF f 5.00:5.00

In this example the rising edge of the clock "clk" causes the rising arrival min:max time at 0.00, and the falling edge arrives at 5.00. Since the rising edge of the clock causes the rising edge of the register clock pin, the clock path is positive unate.

The clock path should be positive or negative unate. Something is probably wrong with the clock network if it is non-unate. A non-unate clock path will report arrivals similar to the foillowing:

% report_arrivals r1/CP (clk ^) r 0.00:0.00 f 0.00:0.00 (clk v) r 5.00:5.00 f 5.00:5.00

Notice that each clock edge causes both rise and fall arrivals at the register clock pin.

If there are no paths to the register clock pin, nothing is printed. Use the report_edges -to command to find the gate driving the clock pin.

% report_edges -to r1/CPi1/ZN -> CP wire ^ -> ^ 0.00:0.00 v -> v 0.00:0.00

This shows that the gate/pin i1/ZN is driving the clock pin. The report_edges -to commond can be used to walk backward or forward through the netlist one gate/net at a time. By checking the arrivals with the report_arrival command you can determine where the path is broken.

No path reported an endpoint

In order for a timing check to be reported, there must be an arrival time at the data pin (the constrained pin) as well as the timing check clock pin. If report_checks -to a register input does not report any paths, check that the input is constrained by a timing check with report_edges -to.

% report_edges -to r1/DCP -> D hold ^ -> ^ -0.04:-0.04 ^ -> v -0.03:-0.03CP -> D setup ^ -> ^ 0.09:0.0 ^ -> v 0.08:0.08in1 -> D wire ^ -> ^ 0.00:0.00 v -> v 0.00:0.00

This reports the setup and hold checks for the D pin of r1.

Next, check the arrival times at the D and CP pins of the register with report_arrivals.

% report_arrivals r1/D (clk1 ^) r 1.00:1.00 f 1.00:1.00% report_arrivals r1/CP (clk1 ^) r 0.00:0.00 f INF:-INF (clk1 v) r INF:-INF f 5.00:5.00

If there are no arrivals on an input port of the design, use the set_input_delay command to specify the arrival times on the port.

Commands

all_clocks

The all_clocks command returns a list of all clocks that have been defined.

all_inputs

[-no_clocks]

-no_clocks

Exclude inputs defined as clock sources.

The all_inputs command returns a list of all input and bidirect ports of the current design.

all_outputs

The all_outputs command returns a list of all output and bidirect ports of the design.

all_registers

[-clock clock_names][-cells | -data_pins | -clock_pins | -async_pins | ‑output_pins][-level_sensitive][-edge_triggered]

-clock clock_names

A list of clock names. Only registers clocked by these clocks are returned.

-cells

Return a list of register instances.

-data_pins

Return the register data pins.

-clock_pins

Return the register clock pins.

-async_pins

Return the register set/clear pins.

-output_pins

Return the register output pins.

-level_sensitive

Return level-sensitive latches.

-edge_triggered

Return edge-triggered registers.

The all_registers command returns a list of register instances or register pins in the design. Options allow the list of registers to be restricted in various ways. The -clock keyword restrcts the registers to those that are clocked by a set of clocks. The -cells option returns the list of registers or latches (the default). The -‑data_pins, -clock_pins, -async_pins and -output_pins options cause all_registers to return a list of register pins rather than instances.

check_setup

[-verbose][-unconstrained_endpoints][-multiple_clock][-no_clock][-no_input_delay][-loops][-generated_clocks][> filename][>> filename]

-verbose

Show offending objects rather than just error counts.

-unconstrained_endpoints

Check path endpoints for timing constraints (timing check or set_output_delay).

-multiple_clock

Check register/latch clock pins for multiple clocks.

-no_clock

Check register/latch clock pins for a clock.

-no_input_delay

Check for inputs that do not have a set_input_delay command.

-loops

Check for combinational logic loops.

-generated_clocks

Check that generated clock source pins have been defined as clocks.

The check_setup command performs sanity checks on the design. Individual checks can be performed with the keywords. If no check keywords are specified all checks are performed. Checks that fail are reported as warnings. If no checks fail nothing is reported. The command returns 1 if there are no warnings for use in scripts.

connect_pin

netport|pin

net

A net to add connections to.

port

A port to connect to net.

Pin

A pin to connect to net.

The connect_pin command connects a port or instance pin to a net.

create_clock

-period period[-name clock_name][-waveform edge_list][-add][pin_list]

-period period

The clock period.

-name clock_name

The name of the clock.

-waveform edge_list

A list of edge rise and fall time.

-add

Add this clock to the clocks on pin_list.

pin_list

A list of pins driven by the clock.

The create_clock command defines the waveform of a clock used by the design.

If no pin_list is specified the clock is virtual. A virtual clock can be refered to by name in input arrival and departure time commands but is not attached to any pins in the design.

If no clock name is specified the name of the first pin is used as the clock name.

If a wavform is not specified the clock rises at zero and falls at half the clock period. The waveform is a list with time the clock rises as the first element and the time it falls as the second element.

If a clock is already defined on a pin the clock is redefined using the new clock parameters. If multiple clocks drive the same pin, use the -add option to prevent the existing definition from being overwritten.

The following command creates a clock with a period of 10 time units that rises at time 0 and falls at 5 time units on the pin named clk1.

create_clock -period 10 clk1

The following command creates a clock with a period of 10 time units that is high at time zero, falls at time 2 and rises at time 8. The clock drives three pins named clk1, clk2, and clk3.

create_clock -period 10 -waveform {8 2} -name clk {clk1 clk2 clk3}

create_generated_clock

[-name clock_name]-source master_pin[-master_clock master_clock][-divide_by divisor][-multiply_by multiplier][-duty_cycle duty_cycle][-invert][-edges edge_list][-edge_shift shift_list][-add]pin_list

-name clock_name

The name of the generated clock.

-source master_pin

A pin or port in the fanout of the master clock that is the source of the generated clock.

-master_clock master_clock

Use -master_clock to specify which source clock to use when multiple clocks are present on master_pin.

-divide_by divisor

Divide the master clock period by divisor.

-multiply_by multiplier

Multiply the master clock period by multiplier.

-duty_cycle duty_cycle

The percent of the period that the generated clock is high (between 0 and 100).

-invert

Invert the master clock.

-edges edge_list

List of master clock edges to use in the generated clock. Edges are numbered from 1. edge_list must be 3 edges long.

-edge_shift shift_list

Not supported.

-add

Add this clock to the existing clocks on pin_list.

pin_list

A list of pins driven by the generated clock.

The create_generated_clock command is used to generate a clock from an existing clock definition. It is used to model clock generation circuits such as clock dividers and phase locked loops.

The -divide_by, -multiply_by and -edges arguments are mutually exclusive.

The -multiply_by option is used to generate a higher frequency clock from the source clock. The period of the generated clock is divided by multiplier. The clock multiplier must be a positive integer. If a duty cycle is specified the generated clock rises at zero and falls at period * duty_cycle / 100. If no duty cycle is specified the source clock edge times are divided by multiplier.

The -divide_by option is used to generate a lower frequency clock from the source clock. The clock divisor must be a positive integer. If the clock divisor is a power of two the source clock period is multiplied by divisor, the clock rise time is the same as the source clock, and the clock fall edge is one half period later. If the clock divisor is not a power of two the source clock waveform edge times are multiplied by divisor.

The -edges option forms the generated clock waveform by selecting edges from the source clock waveform.

If the -invert option is specified the waveform derived above is inverted.

If a clock is already defined on a pin the clock is redefined using the new clock parameters. If multiple clocks drive the same pin, use the -add option to prevent the existing definition from being overwritten.

In the example show below generates a clock named gclk1 on register output pin r1/Q by dividing it by four.

create_clock -period 10 -waveform {1 8} clk1create_generated_clock -name gclk1 -source clk1 -divide_by 4 r1/Q

The generated clock has a period of 40, rises at time 1 and falls at time 21.

In the example shown below the duty cycle is used to define the derived clock waveform.

create_generated_clock -name gclk1 -source clk1 -duty_cycle 50 \ -multiply_by 2 r1/Q

The generated clock has a period of 5, rises at time .5 and falls at time 3.

In the example shown below the first, third and fifth source clock edges are used to define the derived clock waveform.

create_generated_clock -name gclk1 -source clk1 -edges {1 3 5} r1/Q

The generated clock has a period of 20, rises at time 1 and falls at time 11.

create_voltage_area

[-name name][-coordinate coordinates][-guard_band_x guard_x][-guard_band_y guard_y]cells

This command is parsed and ignored by timing analysis.

current_design

[design]

current_instance

[instance]

instance

Not supported.

define_scene

-mode mode_name -liberty liberty_files|-liberty_min liberty_min_files -liberty_max liberty_max_files-spef spef_file| -spef_min spef_min_file -spef_max spef_max_file

mode_name

The SDC mode to use.

liberty_files

List of Liberty files to use.

spef_file

The SPEF parasitics file to use.

The define_scene command defines a scene for a mode (SDC), liberty files and spef parasitics. Define scenes after reading Liberty libraries and SPEF parasitics.Liberty files are specifiec with the name of the liberty library or the filename of the liberty file. If a filename is used, it must be the same as the filename used to read the library with read_liberty..

Use get_scenes to find defined scenes.

delete_clock

[-all] clocks

clocks

A list of clocks to remove.

delete_from_list

list objects

list

A list of objects.

objects

A list of objects to delete from list.

delete_generated_clock

[-all] clocks

clocks

A list of generated clocks to remove.

delete_instance

instance

instance

Instance to delete.

The network editing command delete_instance removes an instance from the design.

delete_net

net

net

Net to delete.

The network editing command delete_net removes a net from the design.

disconnect_pin

netport | pin | -all

net

The net to disconnect pins from.

port

A port to connect to net.

pin

A pin to connect to net.

-all

Disconnect all pins from the net.

Disconnects a port or pin from a net. Parasitics connected to the pin are deleted.

elapsed_run_time

Returns the total clock run time in seconds as a float.

find_timing_paths

[-from from_list |-rise_from from_list |-fall_from from_list][-through through_list |-rise_through through_list |-fall_through through_list][-to to_list |-rise_to to_list |-fall_to to_list][-unconstrained][-path_delay min|min_rise|min_fall |max|max_rise|max_fall |min_max][-group_path_count path_count][-endpoint_path_count endpoint_path_count][-unique_paths_to_endpoint][-scene scene][-slack_max max_slack][-slack_min min_slack][-sort_by_slack][-path_group groups]

-from from_list

Return paths from a list of clocks, instances, ports, register clock pins, or latch data pins.

-rise_from from_list

Return paths from the rising edge of clocks, instances, ports, register clock pins, or latch data pins.

-fall_from from_list

Return paths from the falling edge of clocks, instances, ports, register clock pins, or latch data pins.

-through through_list

Return paths through a list of instances, pins or nets.

-rise_through through_list

Return rising paths through a list of instances, pins or nets.

-fall_through through_list

Return falling paths through a list of instances, pins or nets.

-to to_list

Return paths to a list of clocks, instances, ports or pins.

-rise_to to_list

Return rising paths to a list of clocks, instances, ports or pins.

-fall_to to_list

Return falling paths to a list of clocks, instances, ports or pins.

-unconstrained

Report unconstrained paths also.

-path_delay min

Return min path (hold) checks.

-path_delay min_rise

Return min path (hold) checks for rising endpoints.

-path_delay min_fall

Return min path (hold) checks for falling endpoints.

-path_delay max

Return max path (setup) checks.

-path_delay max_rise

Return max path (setup) checks for rising endpoints.

-path_delay max_fall

Return max path (setup) checks for falling endpoints.

-path_delay min_max

Return max and max path (setup and hold) checks.

-group_path_count path_count

The number of paths to return in each path group.

-endpoint_path_count endpoint_path_count

The number of paths to return for each endpoint.

‑unique_paths_to_endpoint

Return multiple paths to an endpoint that traverse different pins without showing multiple paths with different rise/fall transitions.

-scene scene

Return paths for one process corner.

-slack_max max_slack

Return paths with slack less than max_slack.

-slack_min min_slack

Return paths with slack greater than min_slack.

-sort_by_slack

Sort paths by slack rather than slack within path groups.

-path_group groups

Return paths in path groups. Paths in all groups are returned if this option is not specified.

The find_timing_paths command returns a list of path objects for scripting. Use the get_property function to access properties of the paths.

get_cells

[-hierarchical][-hsc separator][-filter expr][-regexp][-nocase][-quiet][-of_objects objects][patterns]

-hierarchical

Searches hierarchy levels below the current instance for matches.

-hsc separator

Character to use to separate hierarchical instance names in patterns.

-filter expr

A filter expression of the form “property==value”where property is a property supported by the get_property command. See the section “Filter Expressions” for additional forms.

-regexp

Use regular expression matching instead of glob pattern matching.

-nocase

Ignore case when matching. Only valid with –regexp.

-quiet

Do not warn if no matches are found.

-of_objects objects

The name of a pin or net, a list of pins returned by get_pins, or a list of nets returned by get_nets. The –hierarchical option cannot be used with ‑of_objects.

patterns

A list of instance name patterns.

The get_cells command returns a list of all cell instances that match patterns.

get_clocks

[-regexp][-nocase][-filter expr][-quiet]patterns

-regexp

Use regular expression matching instead of glob pattern matching.

-nocase

Ignore case when matching. Only valid with –regexp.

-filter expr

A filter expression of the form “property==value”where property is a property supported by the get_property command. See the section “Filter Expressions” for additional forms.

-quiet

Do not warn if no matches are found.

patterns

A list of clock name patterns.

The get_clocks command returns a list of all clocks that have been defined.

get_fanin

-to sink_list[-flat][-only_cells][-startpoints_only][-levels level_count][-pin_levels pin_count][-trace_arcs timing|enabled|all]

-to sink_list

List of pins, ports, or nets to find the fanin of. For nets, the fanin of driver pins on the nets are returned.

-flat

With –flat pins in the fanin at any hierarchy level are returned. Without ‑flat only pins at the same hierarchy level as the sinks are returned.

-only_cells

Return the instances connected to the pins in the fanin.

-startpoints_only

Only return pins that are startpoints.

-level level_count

Only return pins within level_count instance traversals.

-pin_levels pin_count

Only return pins within pin_count pin traversals.

-trace_arcs timing

Only trace through timing arcs that are not disabled.

-trace_arcs enabled

Only trace through timing arcs that are not disabled.

-trace_arcs all

Trace through all arcs, including disabled ones.

The get_fanin command returns traverses the design from sink_list pins, ports or nets backwards and return the fanin pins or instances.

get_fanout

-from source_list[-flat][-only_cells][-endpoints_only][-levels level_count][-pin_levels pin_count][-trace_arcs timing|enabled|all]

-from source_list

List of pins, ports, or nets to find the fanout of. For nets, the fanout of load pins on the nets are returned.

-flat

With –flat pins in the fanin at any hierarchy level are returned. Without ‑flat only pins at the same hierarchy level as the sinks are returned.

-only_cells

Return the instances connected to the pins in the fanout.

-endpoints_only

Only return pins that are endpoints.

-level level_count

Only return pins within level_count instance traversals.

-pin_levels pin_count

Only return pins within pin_count pin traversals.

-trace_arcs timing

Only trace through timing arcs that are not disabled.

-trace_arcs enabled

Only trace through timing arcs that are not disabled.

-trace_arcs all

Trace through all arcs, including disabled ones.

The get_fanout command returns traverses the design from source_list pins, ports or nets backwards and return the fanout pins or instances.

get_full_name

object

object

A library, cell, port, instance, pin or timing arc object.

Return the name of object. Equivalent to [get_property object full_name].

get_lib_cells

[-of_objects objects][-hsc separator][-filter expr][-regexp][-nocase][-quiet]patterns

-of_objects objects

A list of instance objects.

-hsc separator

Character that separates the library name and cell name in patterns. Defaults to ‘/’.

-filter expr

A filter expression of the form “property==value”where property is a property supported by the get_property command. See the section “Filter Expressions” for additional forms.

-regexp

Use regular expression matching instead of glob pattern matching.

-nocase

Ignore case when matching. Only valid with –regexp.

-quiet

Do not warn if no matches are found.

patterns

A list of library cell name patterns of the form library_name/cell_name.

The get_lib_cells command returns a list of library cells that match pattern. The library name can be prepended to the cell name pattern with the separator character, which defaults to hierarchy_separator.

get_lib_pins

[-of_objects objects][-hsc separator][-filter expr][-regexp][-nocase][-quiet]patterns

-of_objects objects

A list of library cell objects.

-hsc separator

Character that separates the library name, cell name and port name in pattern. Defaults to ‘/’.

-filter expr

A filter expression of the form “property==value”where property is a property supported by the get_property command. See the section “Filter Expressions” for additional forms.

-regexp

Use regular expression matching instead of glob pattern matching.

-nocase

Ignore case when matching. Only valid with –regexp.

-quiet

Do not warn if no matches are found.

patterns

A list of library port name patterns of the form library_name/cell_name/port_name.

The get_lib_pins command returns a list of library ports that match pattern. Use separator to separate the library and cell name patterns from the port name in pattern.

get_libs

[-filter expr][-regexp][-nocase][-quiet]patterns

-filter expr

A filter expression of the form “property==value”where property is a property supported by the get_property command. See the section “Filter Expressions” for additional forms.

-regexp

Use regular expression matching instead of glob pattern matching.

-nocase

Ignore case when matching. Only valid with –regexp.

-quiet

Do not warn if no matches are found.

patterns

A list of library name patterns.

The get_libs command returns a list of clocks that match patterns.

get_nets

[-hierarchical][-hsc separator][-filter expr][-regexp][-nocase][-quiet][-of_objects objects][patterns]

-hierarchical

Searches hierarchy levels below the current instance for matches.

-hsc separator

Character that separates the library name, cell name and port name in pattern. Defaults to ‘/’.

-filter expr

A filter expression of the form “property==value”where property is a property supported by the get_property command. See the section “Filter Expressions” for additional forms.

-regexp

Use regular expression matching instead of glob pattern matching.

-nocase

Ignore case when matching. Only valid with –regexp.

-quiet

Do not warn if no matches are found.

-of_objects objects

The name of a pin or instance, a list of pins returned by get_pins, or a list of instances returned by get_cells. The –hierarchical option cannot be used with –of_objects.

patterns

A list of net name patterns.

The get_nets command returns a list of all nets that match patterns.

get_name

object

object

A library, cell, port, instance, pin or timing arc object.

Return the name of object. Equivalent to [get_property object name].

get_pins

[-hierarchical][-hsc separator][-filter expr][-regexp][-nocase][-quiet][-of_objects objects][patterns]

-hierarchical

Searches hierarchy levels below the current instance for matches.

-hsc separator

Character that separates the library name, cell name and port name in pattern. Defaults to ‘/’.

-filter expr

A filter expression of the form “property==value”where property is a property supported by the get_property command. See the section “Filter Expressions” for additional forms.

-nocase

Ignore case when matching. Only valid with –regexp.

-quiet

Do not warn if no matches are found.

-of_objects objects

The name of a net or instance, a list of nets returned by get_nets, or a list of instances returned by get_cells. The –hierarchical option cannot be used with –of_objects.

patterns

A list of pin name patterns.

The get_pins command returns a list of all instance pins that match patterns.

A useful idiom to find the driver pin for a net is the following.

get_pins -of_objects [get_net net_name] -filter “direction==output”

get_ports

[-filter expr][-regexp][-nocase][-quiet][-of_objects objects][patterns]

-filter expr

A filter expression of the form “property==value”where property is a property supported by the get_property command. See the section “Filter Expressions” for additional forms.

-regexp

Use regular expression matching instead of glob pattern matching.

-nocase

Ignore case when matching. Only valid with –regexp.

-quiet

Do not warn if no matches are found.

-of_objects objects

The name of net or a list of nets returned by get_nets.

patterns

A list of port name patterns.

The get_ports command returns a list of all top level ports that match patterns.

get_property

[-object_type object_type]objectproperty

-object_type object_type

The type of object when it is specified as a name.cell|pin|net|port|clock|library|library_cell|library_pin|timing_arc

object

An object returned by get_cells, get_pins, get_nets, get_ports, get_clocks, get_libs, get_lib_cells, get_lib_pins, or get_timing_arcs, or object name. ‑object_type is required if object is a name.

property

A property name.

The properties for different objects types are shown below.

cell (SDC lib_cell)

base_namefilenamefull_namelibraryname

clock

full_nameis_generated is_propagatedis_virtualnameperiodsources

edge

delay_max_falldelay_min_falldelay_max_risedelay_min_rise full_namefrom_pinsenseto_pin

instance (SDC cell)

cellfull_name is_bufferis_clock_gateis_hierarchicalis_inverteris_macrois_memory liberty_cell nameref_name

liberty_cell (SDC lib_cell)

areabase_name dont_use filenamefull_name is_bufferis_inverteris_memory library name

liberty_port (SDC lib_pin)

capacitancedirection drive_resistancedrive_resistance_max_falldrive_resistance_max_risedrive_resistance_min_falldrive_resistance_min_risefull_name intrinsic_delayintrinsic_delay_max_fallintrinsic_delay_max_riseintrinsic_delay_min_fallintrinsic_delay_min_rise is_register_clocklib_cell name

library

filename (Liberty library only)name full_name

net

full_name name

path (PathEnd)

endpointendpoint_clockendpoint_clock_pinslackstartpointstartpoint_clockpoints

pin

activity (activity in transitions per second, duty cycle, origin)origin is one of globalset_power_activity -globalinputset_power_activity -inputuserset_power_activity -input_ports -pins vcdread_vcd saifread_saifpropagatedpropagated from upstream activitiesclockSDC create_clock or create_generated_clockconstantconstant pins propagated from verilog tie high/low, set_case_analysis, set_logic_one/zero/dc

slew_max_fallslew_max_riseslew_min_fallslew_min_riseclocks clock_domainsdirectionfull_name is_hierarchicalis_portis_register_clocklib_pin_name name slack_maxslack_max_fall slack_max_rise slack_minslack_min_fall slack_min_rise

port

activityslew_max_fallslew_max_riseslew_min_fallslew_min_risedirectionfull_name liberty_portnameslack_maxslack_max_fallslack_max_riseslack_minslack_min_fallslack_min_rise

point (PathRef)

arrivalpinrequiredslack

get_scenes

[-mode mode_name]scene_name

mode_name

Get the scenes for mode_name.

scene_name

A scene name pattern.

The get_scenes command is used to find the scenes matching a pattern or that use an SDC mode.

get_timing_edges

[-from from_pins][-to to_pins][-of_objects objects][-filter expr][patterns]

-from from_pin

A list of pins.

-to to_pin

A list of pins.

-of_objects objects

A list of instances or library cells. The –from and -to options cannot be used with –of_objects.

-filter expr

A filter expression of the form “property==value”where property is a property supported by the get_property command. See the section “Filter Expressions” for additional forms.

The get_timing_edges command returns a list of timing edges (arcs) to, from or between pins. The result can be passed to get_property or set_disable_timing.

group_path

-name group_name[-weight weight][-critical_range range][-from from_list |-rise_from from_list |-fall_from from_list][-through through_list][-rise_through through_list][-fall_through through_list][-to to_list |-rise_to to_list |-fall_to to_list][-default]

-name group_name

The name of the path group.

-weight weight

Not supported.

-critical_range range

Not supported.

-from from_list

Group paths from a list of clocks, instances, ports, register clock pins, or latch data pins.

-rise_from from_list

Group paths from the rising edge of clocks, instances, ports, register clock pins, or latch data pins.

-fall_from from_list

Group paths from the falling edge of clocks, instances, ports, register clock pins, or latch data pins.

-through through_list

Group paths through a list of instances, pins or nets.

-rise_through through_list

Group rising paths through a list of instances, pins or nets.

-fall_through through_list

Group falling paths through a list of instances, pins or nets.

-to to_list

Group paths to a list of clocks, instances, ports or pins.

-rise_to to_list

Group rising paths to a list of clocks, instances, ports or pins.

-fall_to to_list

Group falling paths to a list of clocks, instances, port-s or pins.

-default

Restore the paths in the path group -from/-to/-through/-to to their default path group.

The group_path command is used to group paths reported by the report_checks command. See set_false_path for a description of allowed from_list, through_list and to_list objects.

include

[-echo|-e][-verbose|-v]filename[> log_filename][>> log_filename]

-echo|-e

Print each command before evaluating it.

-verbose|-v

Print each command before evaluating it as well as the result it returns.

filename

The name of the file containing commands to read.

> log_filename

Redirect command output to log_filename.

>> log_filename

Redirect command output and append log_filename.

Read STA/SDC/Tcl commands from filename.

The include command stops and reports any errors encountered while reading a file unless sta_continue_on_error is 1.

link_design

[-no_black_boxes][cell_name]

-no_black_boxes

Do not make empty “black box” cells for instances that reference undefined cells.

cell_name

The top level module/cell name of the design hierarchy to link.

Link (elaborate, flatten) the the top level cell cell_name. The design must be linked after reading netlist and library files. The default value of cell_name is the current design.

The linker creates empty "block box" cells for instances the reference undefined cells when the variable link_create_black_boxes is true. When link_create_black_boxes is false an error is reported and the link fails.

The link_design command returns 1 if the link succeeds and 0 if it fails.

make_instance

inst_pathlib_cell

inst_path

A hierarchical instance name.

lib_cell

The library cell of the new instance.

The make_instance command makes an instance of library cell lib_cell.

make_net

net_name_list

net_name_list

A list of net names.

Creates a net for each hierarchical net name.

read_liberty

[-corner corner][-min][-max][-infer_latches]filename

-corner corner

Use the library for process corner corner delay calculation.

-min

Use library for min delay calculation.

-max

Use library for max delay calculation.

filename

The liberty file name to read.

The read_liberty command reads a Liberty format library file. The first library that is read sets the units used by SDC/TCL commands and reporting. The include_file attribute is supported.

Some Liberty libraries do not include latch groups for cells that are describe transparent latches. In that situation the -infer_latches command flag can be used to infer the latches. The timing arcs required for a latch to be inferred should look like the following:

cell (infered_latch) { pin(D) { direction : input ; timing () { related_pin : "E" ; timing_type : setup_falling ; } timing () { related_pin : "E" ; timing_type : hold_falling ; } } pin(E) { direction : input; } pin(Q) { direction : output ; timing () { related_pin : "D" ; } timing () { related_pin : "E" ; timing_type : rising_edge ; } }}

In this example a positive level-sensitive latch is inferred.

Files compressed with gzip are automatically uncompressed.

read_saif

[-scope scope]filename

scope

The SAIF scope of the current design to extract simulation data. Typically the test bench name and design under test instance name. Scope levels are separated with ‘/’.

filename

The name of the SAIF file to read.

The read_saif command reads a SAIF (Switching Activity Interchange Format) file from a Verilog simulation and extracts pin activities and duty cycles for use in power estimation. Files compressed with gzip are supported. Annotated activities are propagated to the fanout of the annotated pins.

read_sdc

[-mode mode_name][-echo]filename

mode_name

Mode for the SDC commands in the file.

-echo

Print each command before evaluating it.

filename

SDC command file.

Read SDC commands from filename.

If the mode does not exist it is created. Multiple SDC files can append commands to a mode by using the -mode_name argument for each one. If no -mode arguement is is used the commands are added to the current mode.

The read_sdc command stops and reports any errors encountered while reading a file unless sta_continue_on_error is 1.

Files compressed with gzip are automatically uncompressed.

read_sdf

[-scene scene][-unescaped_dividers]filename

scene

Scene delays to annotate.

-unescaped_dividers

With this option path names in the SDF do not have to escape hierarchy dividers when the path name is escaped. For example, the escaped Verilog name "\inst1/inst2 " can be referenced as "inst1/inst2". The correct SDF name is "inst1\/inst2", since the divider does not represent a change in hierarchy in this case.

filename

The name of the SDF file to read.

Read SDF delays from a file. The min and max values in the SDF tuples are used to annotate the delays for corner. The typical values in the SDF tuples are ignored. If multiple scenes are defined -scene must be specified. SDC annotation for mcmm analysis must follow the scene definitions.

Files compressed with gzip are automatically uncompressed.

INCREMENT is supported as an alias for INCREMENTAL.

The following SDF statements are not supported.

PORTINSTANCE wildcards

read_spef

[-name name][-keep_capacitive_coupling][-coupling_reduction_factor factor][-reduce][-path path]filename

name

The name of the SPEF parasitics to use for defining scenes. The default is the base name of filename.

path

Hierarchical block instance path to annotate with parasitics.

‑keep_capacitive_coupling

Keep coupling capacitors in parasitic networks rather than converting them to grounded capacitors.

‑coupling_reduction_factorfactor

Factor to multiply coupling capacitance by when reducing parasitic networks. The default value is 1.0.

filename

The name of the parasitics file to read.

The read_spef command reads a file of net parasitics in SPEF format. Use the ‑report_parasitic_annotation command to check for nets that are not annotated.

Files compressed with gzip are automatically uncompressed.

Separate min/max parasitics can be annotated for each scene mode/corner.

read_spef -name min spef1read_spef -name max spef2define_scene -mode mode1 -spef_min min -spef_max max

Coupling capacitors are multiplied by the –coupling_reduction_factor when a parasitic network is reduced.

The following SPEF constructs are ignored.

*DESIGN_FLOW (all values are ignored)*S slews*D driving cell*I pin capacitances (library cell capacitances are used instead)*Q r_net load poles*K r_net load residues

If the SPEF file contains triplet values the first value is used.

Parasitic networks (DSPEF) can be annotated on hierarchical blocks using the -path argument to specify the instance path to the block. Parasitic networks in the higher level netlist are stitched together at the hierarchical pins of the blocks.

read_vcd

[-scope scope][-mode mode_name]filename

scope

The VCD scope of the current design to extract simulation data. Typically the test bench name and design under test instance name. Scope levels are separated with ‘/’.

mode_name

Mode to annotate activities.

filename

The name of the VCD file to read.

The read_vcd command reads a VCD (Value Change Dump) file from a Verilog simulation and extracts pin activities and duty cycles for use in power estimation. Files compressed with gzip are supported. Annotated activities are propagated to the fanout of the annotated pins.

read_verilog

filename

filename

The name of the verilog file to read.

The read_verilog command reads a gate level verilog netlist. After all verilog netlist and Liberty libraries are read the design must be linked with the link_design command.

Verilog 2001 module port declaratations are supported. An example is shown below.

module top (input in1, in2, clk1, clk2, clk3, output out);

Files compressed with gzip are automatically uncompressed.

replace_cell

instance_listreplacement_cell

instance_list

A list of instances to swap the cell.

replacement_cell

The replacement lib cell.

The replace_cell command changes the cell of an instance. The replacement cell must have the same port list (number, name, and order) as the instance's existing cell for the replacement to be successful.

replace_activity_annotation

[-report_unannotated][-report_annotated]

-report_unannotated

Report unannotated pins.

-report_unannotated

Report annotated pins.

Report a summary of pins that are annotated by read_vcd, read_saif or set_power_activity. Sequential internal pins and hierarchical pins are ignored.

report_annotated_check

[-setup][-hold][-recovery][-removal][-nochange][-width][-period][-max_skew][-max_line lines][-report_annotated][-report_unannotated][-constant_arcs]

-setup

Report annotated setup checks.

-hold

Report annotated hold checks.

-recovery

Report annotated recovery checks.

-removal

Report annotated removal checks.

-nochange

Report annotated nochange checks.

-width

Report annotated width checks.

-period

Report annotated period checks.

-max_skew

Report annotated max skew checks.

-max_line lines

Maximum number of lines listed by the –report_annotated and ‑report_unannotated options.

-report_annotated

Report annotated timing arcs.

-report_unannotated

Report unannotated timing arcs.

-constant_arcs

Report separate annotation counts for arcs disabled by logic constants (set_logic_one, set_logic_zero).

The report_annotated_check command reports a summary of SDF timing check annotation. The -report_annotated and –report_annotated options can be used to list arcs that are annotated or not annotated.

report_annotated_delay

[-cell][-net][-from_in_ports][-to_out_ports][-max_lines lines][-report_annotated][-report_unannotated][-constant_arcs]

-cell

Report annotated cell delays.

-net

Report annotated internal net delays.

-from_in_ports

Report annotated delays from input ports.

-to_out_ports

Report annotated delays to output ports.

-max_lines lines

Maximum number of lines listed by the –report_annotated and ‑report_unannotated options.

-report_annotated

Report annotated timing arcs.

-report_unannotated

Report unannotated timing arcs.

-constant_arcs

Report separate annotation counts for arcs disabled by logic constants (set_logic_one, set_logic_zero).

The report_annotated_delay command reports a summary of SDF delay annotation. Without the ‑from_in_ports and –to_out_ports options arcs to and from top level ports are not reported. The ‑report_annotated and –report_unannotated options can be used to list arcs that are annotated or not annotated.

report_checks

[-from from_list |-rise_from from_list |-fall_from from_list][-through through_list |-rise_through through_list |-fall_through through_list][-to to_list |-rise_to to_list |-fall_to to_list][-unconstrained][-path_delay min|min_rise|min_fall |max|max_rise|max_fall |min_max][-group_path_count path_count][-endpoint_path_count endpoint_path_count][-unique_paths_to_endpoint][-unique_edges_to_endpoint][-scenes scenes][-slack_max max_slack][-slack_min min_slack][-sort_by_slack][-path_group groups][-format end|full|short|summary |full_clock|full_clock_expanded |json][-fields fields][-digits digits][-no_line_split][> filename][>> filename]

-from from_list

Report paths from a list of clocks, instances, ports, register clock pins, or latch data pins.

-rise_from from_list

Report paths from the rising edge of clocks, instances, ports, register clock pins, or latch data pins.

-fall_from from_list

Report paths from the falling edge of clocks, instances, ports, register clock pins, or latch data pins.

-through through_list

Report paths through a list of instances, pins or nets.

-rise_through through_list

Report rising paths through a list of instances, pins or nets.

-fall_through through_list

Report falling paths through a list of instances, pins or nets.

-to to_list

Report paths to a list of clocks, instances, ports or pins.

-rise_to to_list

Report rising paths to a list of clocks, instances, ports or pins.

-fall_to to_list

Report falling paths to a list of clocks, instances, ports or pins.

-unconstrained

Report unconstrained paths also. The unconstrained path group is not reported without this option.

-path_delay min

Report min path (hold) checks.

-path_delay min_rise

Report min path (hold) checks for rising endpoints.

-path_delay min_fall

Report min path (hold) checks for falling endpoints.

-path_delay max

Report max path (setup) checks.

-path_delay max_rise

Report max path (setup) checks for rising endpoints.

-path_delay max_fall

Report max path (setup) checks for falling endpoints.

-path_delay min_max

Report max and max path (setup and hold) checks.

-group_path_count path_count

The number of paths to report in each path group. The default is 1.

-endpoint_path_count endpoint_path_count

The number of paths to report for each endpoint. The default is 1.

‑unique_paths_to_endpoint

When multiple paths to an endpoint are specified with ‑endpoint_path_count, many of the paths may differ only in the rise/fall edges of the pins in the paths. With this option only the worst path through the set of pins is reported.

‑unique_edges_to_endpoint

When multiple paths to an endpoint are specified with ‑endpoint_path_count, conditional timing arcs result in paths that through the same pins and rise/fall edges. With this option only the worst path through the set of pins and rise/fall edges is reported.

scenes

Report paths for one process corner. The default is to report paths for all process corners.

max_slack

Only report paths with less slack than max_slack.

min_slack

Only report paths with more slack than min_slack.

-sort_by_slack

Sort paths by slack rather than slack grouped by path group.

groups

List of path groups to report. The default is to report all path groups.

-format end

Report path ends in one line with delay, required time and slack.

-format full

Report path start and end points and the path. This is the default path type.

-format full_clock

Report path start and end points, the path, and the source and and target clock paths.

-format full_clock_expanded

Report path start and end points, the path, and the source and and target clock paths. If the clock is generated and propagated, the path from the clock source pin is also reported.

-format short

Report only path start and end points.

-format summary

Report only path ends with delay.

-format json

Report in json format. -fields is ignored.

fields

List of capacitance|slew|input_pins|hierarchical_pins|nets|fanout|src_attr|variation

digits

The number of digits after the decimal point to report. The default value is the variable sta_report_default_digits.

-no_line_splits

Do not split long lines into multiple lines.

The report_checks command reports paths in the design. Paths are reported in groups by capture clock, unclocked path delays, gated clocks and unconstrained.

See set_false_path for a description of allowed from_list, through_list and to_list objects.

report_check_types

[-scenes scenes][-violators][-verbose][-fields fields][-format slack_only|end][-max_delay][-min_delay][-recovery][-removal][-clock_gating_setup][-clock_gating_hold][-max_slew][-min_slew][-min_pulse_width][-min_period][-digits digits][-no_split_lines][> filename][>> filename]

scenes

Report checks for some scenes. The default value is all scenes.

-violators

Report all violated timing and design rule constraints.

-verbose

Use a verbose output format.

-format slack_only

Report the minimum slack for each timing check.

-format end

Report the endpoint for each check.

fields

List of capacitance|slew|input_pins|hierarchical_pins|nets|fanout|src_attr|variation

-max_delay

Report setup and max delay path delay constraints.

-min_delay

Report hold and min delay path delay constraints.

-recovery

Report asynchronous recovery checks.

-removal

Report asynchronous removal checks.

-clock_gating_setup

Report gated clock enable setup checks.

-clock_gating_hold

Report gated clock hold setup checks.

-max_slew

Report max transition design rule checks.

-max_skew

Report max skew design rule checks.

-min_pulse_width

Report min pulse width design rule checks.

-min_period

Report min period design rule checks.

-min_slew

Report min slew design rule checks.

-digits digits

The number of digits after the decimal point to report. The default value is the variable sta_report_default_digits.

-no_split_lines

Do not split long lines into multiple lines.

The report_check_types command reports the slack for each type of timing and design rule constraint. The keyword options allow a subset of the constraint types to be reported.

report_clock_latency

[-clocks clocks][-scenes scenes][-include_internal_latency][-digits digits]

clocks

The clocks to report. The default value is all c

scenes

Report clocks for scenes. The default value is all clocks in scenes modes.

-include_internal_latency

Include internal clock latency from liberty min/max_clock_tree_path timing groups.

digits

The number of digits to report for delays.

Report the clock network latency.

report_clock_min_period

[-clocks clocks][-scenes scenes][-include_port_paths]

clocks

The clocks to report.

-include_port_paths

Include paths from input port and to output ports.

Report the minimum period and maximum frequency for clocks. If the -clocks argument is not specified all clocks are reported. The minimum period is determined by examining the smallest slack paths between registers the rising edges of the clock or between falling edges of the clock. Paths between different clocks, different clock edges of the same clock, level sensitive latches, or paths constrained by set_multicycle_path, set_max_path are not considered.

report_clock_properties

[clock_names]

clock_names

List of clock names to report.

The report_clock_properties command reports the period and rise/fall edge times for each clock that has been defined.

report_clock_skew

[-setup|-hold][-clocks clocks][-scenes scenes][-include_internal_latency][-digits digits]

-setup

Report skew for setup checks.

-hold

Report skew for hold checks.

clocks

The clocks to report. The default value is all clocks in scenes modes.

scenes

Report clocks for scenes. The default value is all scenes.

-include_internal_latency

Include internal clock latency from liberty min/max_clock_tree_path timing groups.

-digits digits

The number of digits to report for delays.

Report the maximum difference in clock arrival between every source and target register that has a path between the source and target registers.

report_dcalc

[-from from_pin][-to to_pin][-scene scene][-min][-max][-digits digits][> filename][>> filename]

from_pin

Report delay calculations for timing arcs from instance input pin from_pin.

to_pin

Report delay calculations for timing arcs to instance output pin to_pin.

scene

Report paths for process scene. The -scene keyword is required if more than one process corner is defined.

-min

Report delay calculation for min delays.

-max

Report delay calculation for max delays.

-digits digits

The number of digits after the decimal point to report. The default is sta_report_default_digits.

The report_dcalc command shows how the delays between instance pins are calculated. It is useful for debugging problems with delay calculation.

report_disabled_edges

The report_disabled_edges command reports disabled timing arcs along with the reason they are disabled. Each disabled timing arc is reported as the instance name along with the from and to ports of the arc. The disable reason is shown next. Arcs that are disabled with set_disable_timing are reported with constraint as the reason. Arcs that are disabled by constants are reported with constant as the reason along with the constant instance pin and value. Arcs that are disabled to break combinational feedback loops are reported with loop as the reason.

> report_disabled_edgesu1 A B constant B=0

report_edges

[-from from_pin][-to to_pin][-report_variation][-digits digits]

from_pin

Report edges/timing arcs from pin from_pin.

to_pin

Report edges/timing arcs to pin to_pin.

-report_variation

digits

The number of digits after the decimal point to report. The default value is the variable sta_report_default_digits.

Report the edges/timing arcs and their delays in the timing graph from/to/between pins.

report_instance

instance_path[> filename][>> filename]

instance_path

Hierarchical path to an instance.

report_lib_cell

cell_name[> filename][>> filename]

cell_name

The name of a library cell.

Describe the liberty library cell cell_name.

report_net

[-digits digits]net_path[> filename][>> filename]

digits

The number of digits after the decimal point to report. The default value is the variable sta_report_default_digits.

net_path

Hierarchical path to a net.

Report the connections and capacitance of a net.

report_parasitic_annotation

[-report_unannotated][> filename][>> filename]

-report_unannotated

Report unannotated and partially annotated nets.

Report SPEF parasitic annotation completeness.

report_power

[-instances instances][-highest_power_instances count][-digits digits][> filename][>> filename]

-instances instances

Report the power for each instance of instances. If the instance is hierarchical the total power for the instances inside the hierarchical instance is reported.

-highest_power_instances count

Report the power for the count highest power instances.

-digits digits

The number of digits after the decimal point to report. The default value is the variable sta_report_default_digits.

The report_power command uses static power analysis based on propagated or annotated pin activities in the circuit using Liberty power models. The internal, switching, leakage and total power are reported. Design power is reported separately for combinational, sequential, macro and pad groups. Power values are reported in watts.

The read_vcd or read_saif commands can be used to read activities from a file based on simulation. If no simulation activities are available, the set_power_activity command should be used to set the activity of input ports or pins in the design. The default input activity and duty for inputs are 0.1 and 0.5 respectively. The activities are propagated from annotated input ports or pins through gates and used in the power calculations.

Group Internal Switching Leakage Total Power Power Power Power----------------------------------------------------------------Sequential 3.29e-06 3.41e-08 2.37e-07 3.56e-06 92.4%Combinational 1.86e-07 3.31e-08 7.51e-08 2.94e-07 7.6%Macro 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.0%Pad 0.00e+00 0.00e+00 0.00e+00 0.00e+00 0.0%---------------------------------------------------------------Total 3.48e-06 6.72e-08 3.12e-07 3.86e-06 100.0% 90.2% 1.7% 8.1%

report_slews

[-scenes scenes][-report_variation][-digits digits]pin

scenes

Report slews for process for scenes process corners.

-report_variation

Report SSTA distribution parameters.

-digits digits

The number of digits after the decimal point to report. The default value is the variable sta_report_default_digits.

pin

Report the slews at pin

report_tns

[-min][-max][-digits digits]

-max

Report the total max/setup slack.

-min

Report the total min/hold slack.

-digits digits

The number of digits after the decimal point to report. The default value is the variable sta_report_default_digits.

Report the total negative slack.

report_units

Report the units used for command arguments and reporting.

report_units time 1ns capacitance 1pF resistance 1kohm voltage 1v current 1A power 1pW distance 1um

report_wns

[-min][-max][-digits digits]

-max

Report the worst max/setup slack.

-min

Report the worst min/hold slack.

-digits digits

The number of digits after the decimal point to report. The default value is the variable sta_report_default_digits.

Report the worst negative slack. If the worst slack is positive, zero is reported.

report_worst_slack

[-min][-max][-digits digits]

-max

Report the worst max/setup slack.

-min

Report the worst min/hold slack.

-digits digits

The number of digits after the decimal point to report. The default value is the variable sta_report_default_digits.

set_assigned_check

-setup|-hold|-recovery|-removal[-rise][-fall][-scene scene][-min][-max][-from from_pins][-to to_pins][-clock rise|fall][-cond sdf_cond][-worst]margin

-setup

Annotate setup timing checks.

-hold

Annotate hold timing checks.

-recovery

Annotate recovery timing checks.

-removal

Annotate removal timing checks.

-rise

Annotate rising delays.

-fall

Annotate falling delays.

scene

The name of a scene. The -scene keyword is required if more than one scene is defined.

-min

Annotate the minimum value of the process corner.

-max

Annotate the maximum value of the process corner.

from_pins

A list of pins for the clock.

to_pins

A list of pins for the data.

-clock rise|fall

The timing check clock pin transition.

margin

The timing check margin.

The set_assigned_check command is used to annotate the timing checks between two pins on an instance. The annotated delay overrides the calculated delay. This command is an interactive way to back-annotate delays like an SDF file.

set_assigned_delay

-cell|-net[-rise][-fall][-scene scene][-min][-max][-from from_pins][-to to_pins]delay

-cell

Annotate the delays between two pins on an instance.

-net

Annotate the delays between two pins on a net.

-rise

Annotate the rising delays.

-fall

Annotate the falling delays.

scene

The name of a scene. The -scene keyword is required if more than one scene is defined.

-min

Annotate the minimum delays.

-max

Annotate the maximum delays.

from_pins

A list of pins.

to_pins

A list of pins.

delay

The delay between from_pins and to_pins.

The set_assigned_delay command is used to annotate the delays between two pins on an instance or net. The annotated delay overrides the calculated delay. This command is an interactive way to back-annotate delays like an SDF file.

set_assigned_transition

[-rise][-fall][-scene scene][-min][-max]slewpin_list

-rise

Annotate the rising transition.

-fall

Annotate the falling transition.

scene

Annotate delays for scene.

-min

Annotate the minimum transition time.

-max

Annotate the maximum transition time.

slew

The pin transition time.

pin_list

A list of pins.

The set_assigned_transition command is used to annotate the transition time (slew) of a pin. The annotated transition time overrides the calculated transition time.

set_case_analysis

0|1|zero|one|rise|rising|fall|fallingport_or_pin_list

port_or_pin_list

A list of ports or pins.

The set_case_analysis command sets the signal on a port or pin to a constant logic value. No paths are propagated from constant pins. Constant values set with the set_case_analysis command are propagated through downstream gates.

Conditional timing arcs with mode groups are controlled by logic values on the instance pins.

set_clock_gating_check

[-setup setup_time][-hold hold_time][-rise][-fall][-high][-low][objects]

-setup setup_time

Clock enable setup margin.

-hold hold_time

Clock enable hold margin.

-rise

The setup/hold margin is for the rising edge of the clock enable.

-fall

The setup/hold margin is for the falling edge of the clock enable.

-high

The gating clock is active high (pin and instance objects only).

-low

The gating clock is active low (pin and instance objects only).

objects

A list of clocks, instances, pins or ports.

The set_clock_gating_check command is used to add setup or hold timing checks for data signals used to gate clocks.

If no objects are specified the setup/hold margin is global and applies to all clock gating circuits in the design. If neither of the -rise and -fall options are used the setup/hold margin applies to the rising and falling edges of the clock gating signal.

Normally the library cell function is used to determine the active state of the clock. The clock is active high for AND/NAND functions and active low for OR/NOR functions. The -high and -low options are used to specify the active state of the clock for other cells, such as a MUX.

If multiple set_clock_gating_check commands apply to a clock gating instance he priority of the commands is shown below (highest to lowest priority).

clock enable pininstanceclock pinclockglobal

set_clock_groups

[-name name][-logically_exclusive][-physically_exclusive][-asynchronous][-allow_paths]-group clocks

-name name

The clock group name.

-logically_exclusive

The clocks in different groups do not interact logically but can be physically present on the same chip. Paths between clock groups are considered for noise analysis.

-physically_exclusive

The clocks in different groups cannot be present at the same time on a chip. Paths between clock groups are not considered for noise analysis.

-asynchronous

The clock groups are asynchronous. Paths between clock groups are considered for noise analysis.

-allow_paths

clocks

A list of clocks in the group.

The set_clock_groups command is used to define groups of clocks that interact with each other. Clocks in different groups do not interact and paths between them are not reported. Use a –group argument for each clock group.

set_clock_latency

[-source][-clock clock][-rise][-fall][-min][-max]delayobjects

-source

The latency is at the clock source.

-clock clock

If multiple clocks are defined at a pin this use this option to specify the latency for a specific clock.

-rise

The latency is for the rising edge of the clock.

-fall

The latency is for the falling edge of the clock.

-min

delay is the minimum latency.

-max

delay is the maximum latency.

delay

Clock source or insertion delay.

objects

A list of clocks, pins or ports.

The set_clock_latency command describes expected delays of the clock tree when anxsalyzing a design using ideal clocks. Use the -source option to specify latency at the clock source, also known as insertion delay. Source latency is delay in the clock tree that is external to the design or a clock tree internal to an instance that implements a complex logic function.set_clock_latency removes propagated clock properties for the clocks and pins objects.

set_clock_transition

[-rise][-fall][-min][-max]transitionclocks

-rise

Set the transition time for the rising edge of the clock.

-fall

Set the transition time for the falling edge of the clock.

-min

Set the min transition time.

-max

Set the min transition time.

transition

Clock transition time (slew).

clocks

A list of clocks.

The set_clock_transition command describes expected transition times of the clock tree when analyzing a design using ideal clocks.

set_clock_uncertainty

[-from|-rise_from|-fall_from from_clock][-to|-rise_to|-fall_to to_clock][-rise][-fall][-setup][-hold]uncertainty[objects]

-from from_clock

Inter-clock uncertainty source clock.

-to to_clock

Inter-clock uncertainty target clock.

-rise

Inter-clock target clock rise edge, alternative to ‑rise_to.Inter-clock target clock rise edge, alternative to ‑rise_to.

-fall

Inter-clock target clock rise edge, alternative to ‑fall_to.

-setup

uncertainty is for setup checks.

-hold

uncertainty is for hold checks.

uncertainty

Clock uncertainty.

objects

A list of clocks, ports or pins.

The set_clock_uncertainty command specifies the uncertainty or jitter in a clock. The uncertainty for a clock can be specified on its source pin or port, or the clock itself.

set_clock_uncertainty .1 [get_clock clk1]

Inter-clock uncertainty between the source and target clocks of timing checks is specified with the ‑from|‑rise_from|-fall_from and ‑to|‑rise_to|-fall_to arguments .

set_clock_uncertainty -from [get_clock clk1] -to [get_clocks clk2] .1

The following commands are equivalent.

set_clock_uncertainty -from [get_clock clk1] -rise_to [get_clocks clk2] .1set_clock_uncertainty -from [get_clock clk1] -to [get_clocks clk2] -rise .1

set_cmd_units

[-capacitance cap_unit][-resistance res_unit][-time time_unit][-voltage voltage_unit][-current current_unit][-power power_unit][-distance distance_unit]

-capacitance cap_unit

The capacitance scale factor followed by 'f'.

-resistance res_unit

The resistance scale factor followed by 'ohm'.

-time time_unit

The time scale factor followed by 's'.

-voltage voltage_unit

The voltage scale factor followed by 'v'.

-current current_unit

The current scale factor followed by 'A'.

-power power_unit

The power scale factor followed by 'w'.

-distance distance_unit

The distance scale factor followed by 'm'.

The set_cmd_units command is used to change the units used by the STA command interpreter when parsing commands and reporting results. The default units are the units specified in the first Liberty library file that is read.

Units are specified as a scale factor followed by a unit name. The scale factors are as follows.

M 1E+6k 1E+3m 1E-3u 1E-6n 1E-9p 1E-12f 1E-15

An example of the set_units command is shown below.

set_cmd_units -time ns -capacitance pF -current mA -voltage V -resistance kOhm -distance um

set_data_check

[-from|-rise_from|-fall_from from_pin][-to|-rise_to|-fall_to to_pin][-setup][-hold][-clock clock]margin

-from from_pin

A pin used as the timing check reference.

-to to_pin

A pin that the setup/hold check is applied to.

-setup

Add a setup timing check.

-hold

Add a hold timing check.

-clock clock

The setup/hold check clock.

margin

The setup or hold time margin.

The set_data_check command is used to add a setup or hold timing check between two pins.

set_disable_inferred_clock_gating

objects

objects

A list of clock gating instances, clock gating pins, or clock enable pins.

The set_disable_inferred_clock_gating command disables clock gating checks on a clock gating instance, clock gating pin, or clock gating enable pin.

set_disable_timing

[-from from_port][-to to_port]objects

-from from_port

-to to_port

objects

A list of instances, ports, pins, cells, cell/port, or library/cell/port.

The set_disable_timing command is used to disable paths though pins in the design. There are many different forms of the command depending on the objects specified in objects.

All timing paths though an instance are disabled when objects contains an instance. Timing checks in the instance are not disabled.

set_disable_timing u2

The -from and -to options can be used to restrict the disabled path to those from, to or between specific pins on the instance.

set_disable_timing -from A u2set_disable_timing -to Z u2set_disable_timing -from A -to Z u2

A list of top level ports or instance pins can also be disabled.

set_disable_timing u2/Zset_disable_timing in1

Timing paths though all instances of a library cell in the design can be disabled by naming the cell using a hierarchy separator between the library and cell name. Paths from or to a cell port can be disabled with the -from and -to options or a port name after library and cell names.

set_disable_timing liberty1/snl_bufx2set_disable_timing -from A liberty1/snl_bufxset_disable_timing -to Z liberty1/snl_bufxset_disable_timing liberty1/snl_bufx2/A

set_drive

[-rise][-fall][-max][-min]resistanceports

-rise

Set the drive rise resistance.

-fall

Set the drive fall resistance.

-max

Set the maximum resistance.

-min

Set the minimum resistance.

resistance

The external drive resistance.

ports

A list of ports.

The set_drive command describes the resistance of an input port external driver.

set_driving_cell

[-lib_cell cell_name][-library library][-rise][-fall][-min][-max][-pin pin][-from_pin from_pin][-input_transition_rise trans_rise][-input_transition_fall trans_fall]ports

-lib_cell cell_name

The driving cell.

-library library

The driving cell library.

-rise

Set the driving cell for a rising edge.

-fall

Set the driving cell for a falling edge.

-max

Set the driving cell for max delays.

-min

Set the driving cell for min delays.

-pin pin

The output port of the driving cell.

-from_pin from_pin

Use timing arcs from from_pin to the output pin.

-input_transition_rise trans_rise

The transition time for a rising input at from_pin.

-input_transition_fall trans_fall

The transition time for a falling input at from_pin.

ports

A list of ports.

The set_driving_cell command describes an input port external driver.

set_false_path

[-setup][-hold][-rise][-fall][-from from_list][-rise_from from_list][-fall_from from_list][-through through_list][-rise_through through_list][-fall_through through_list][-to to_list][-rise_to to_list][-fall_to to_list][-reset_path]

-setup

Apply to setup checks.

-hold

Apply to hold checks.

-rise

Apply to rising path edges.

-fall

Apply to falling path edges.

-reset_path

Remove any matching set_false_path, set_multicycle_path, set_max_delay, set_min_delay exceptions first.

-from from_list

A list of clocks, instances, ports or pins.

-through through_list

A list of instances, pins or nets.

-to to_list

A list of clocks, instances, ports or pins.

The set_false_path command disables timing along a path from, through and to a group of design objects.

Objects in from_list can be clocks, register/latch instances, or register/latch clock pins. The -rise_from and -fall_from keywords restrict the false paths to a specific clock edge.

Objects in through_list can be nets, instances, instance pins, or hierarchical pins,. The -rise_through and -fall_through keywords restrict the false paths to a specific path edge that traverses through the object.

Objects in to_list can be clocks, register/latch instances, or register/latch clock pins. The -rise_to and -fall_to keywords restrict the false paths to a specific transition at the path end.

set_fanout_load

fanoutport_list

This command is ignored.

set_hierarchy_separator

separator

separator

Character used to separate hierarchical names.

Set the character used to separate names in a hierarchical instance, net or pin name. This separator is used by the command interpreter to read arguments and print results. The default separator is '/'.

set_ideal_latency

[-rise] [-fall] [-min] [-max] delay objects

The set_ideal_latency command is parsed but ignored.

set_ideal_network

[-no_propagation] objects

The set_ideal_network command is parsed but ignored.

set_ideal_transition

[-rise] [-fall] [-min] [-max] transition_time objects

The set_ideal_transition command is parsed but ignored.

set_input_delay

[-rise][-fall][-max][-min][-clock clock][-clock_fall][-reference_pin ref_pin][-source_latency_included][-network_latency_included][-add_delay]delayport_pin_list

-rise

Set the arrival time for the rising edge of the input.

-fall

Set the arrival time for the falling edge of the input.

-max

Set the maximum arrival time.

-min

Set the minimum arrival time.

-clock clock

The arrival time is from clock.

-clock_fall

The arrival time is from the falling edge of clock.

-reference_pin ref_pin

The arrival time is with respect to the clock that arrives at ref_pin.

-source_latency_included

D no add the clock source latency (insertion delay) to the delay value.

-network_latency_included

Do not add the clock latency to the delay value when the clock is ideal.

-add_delay

Add this arrival to any existing arrivals.

delay

The arrival time after clock.

pin_port_list

A list of pins or ports.

The set_input_delay command is used to specify the arrival time of an input signal.

The following command sets the min, max, rise and fall times on the in1 input port 1.0 time units after the rising edge of clk1.

set_input_delay -clock clk1 1.0 [get_ports in1]

Use multiple commands with the -add_delay option to specify separate arrival times for min, max, rise and fall times or multiple clocks. For example, the following specifies separate arrival times with respect to clocks clk1 and clk2.

set_input_delay -clock clk1 1.0 [get_ports in1]set_input_delay -add_delay -clock clk2 2.0 [get_ports in1]

The –reference_pin option is used to specify an arrival time with respect to the arrival on a pin in the clock network. For propagated clocks, the input arrival time is relative to the clock arrival time at the reference pin (the clock source latency and network latency from the clock source to the reference pin). For ideal clocks, input arrival time is relative to the reference pin clock source latency. With the -clock_fall flag the arrival time is relative to the falling transition at the reference pin. If no clocks arrive at the reference pin the set_input_delay command is ignored. If no -clock is specified the arrival time is with respect to all clocks that arrive at the reference pin. The -source_latency_included and -network_latency_included options cannot be used with -reference_pin.

Paths from inputs that do not have an arrival time defined by set_input_delay are not reported. Set the sta_input_port_default_clock variable to 1 to report paths from inputs without a set_input_delay.

set_input_transition

[-rise][-fall][-max][-min]transitionport_list

-rise

Set the rising edge transition.

-fall

Set the falling edge transition.

-max

Set the minimum transition time.

-min

Set the maximum transition time.

transition

The transition time (slew).

port_list

A list of ports.

The set_input_transition command is used to specify the transition time (slew) of an input signal.

set_level_shifter_strategy

[-rule rule_type]

This command is parsed and ignored by timing analysis.

set_level_shifter_threshold

[-voltage voltage]

This command is parsed and ignored by timing analysis.

set_load

[-rise][-fall][-max][-min][-subtract_pin_load][-pin_load][-wire_load]capacitanceobjects

-rise

Set the external port rising capacitance (ports only).

-fall

Set the external port falling capacitance (ports only).

-max

Set the max capacitance.

-min

Set the min capacitance.

-subtract_pin_load

Subtract the capacitance of all instance pins connected to the net from capacitance (nets only). If the resulting capacitance is negative, zero is used. Pin capacitances are ignored by delay calculation when this option is used.

-pin_load

capacitance is external instance pin capacitance (ports only).

-wire_load

capacitance is external wire capacitance (ports only).

capacitance

The capacitance, in library capacitance units.

objects

A list of nets or ports.

The set_load command annotates wire capacitance on a net or external capacitance on a port. There are four different uses for the set_load commanc:

set_load -wire_load port external port wire capacitanceset_load -pin_load port external port pin capacitanceset_load port same as -pin_loadset_load net net wire capacitance

External port capacitance can be annotated separately with the -pin_load and ‑wire_load options. Without the -pin_load and -wire_load options pin capacitance is annotated.

When annotating net wire capacitance with the -subtract_pin_load option the capacitance of all instance pins connected to the net is subtracted from capacitance. Setting the capacitance on a net overrides SPEF parasitics for delay calculation.

set_logic_dc

port_list

port_pin_list

List of ports or pins.

Set a port or pin to a constant unknown logic value. No paths are propagated from constant pins.

set_logic_one

port_list

port_pin_list

List of ports or pins.

Set a port or pin to a constant logic one value. No paths are propagated from constant pins. Constant values set with the set_logic_one command are not propagated through downstream gates.

set_logic_zero

port_list

port_pin_list

List of ports or pins.

Set a port or pin to a constant logic zero value. No paths are propagated from constant pins. Constant values set with the set_logic_zero command are not propagated through downstream gates.

set_max_area

area

area

The set_max_area command is ignored during timing but is included in SDC files that are written.

set_max_capacitance

capacitanceobjects

capacitance

objects

List of ports or cells.

The set_max_capacitance command is ignored during timing but is included in SDC files that are written.

set_max_delay

[-rise][-fall][-from from_list][-rise_from from_list][-fall_from from_list][-through through_list][-rise_through through_list][-fall_through through_list][-to to_list][-rise_to to_list][-fall_to to_list][-ignore_clock_latency][-probe][-reset_path]delay

-rise

Set max delay for rising paths.

-fall

Set max delay for falling paths.

-from from_list

A list of clocks, instances, ports or pins.

-through through_list

A list of instances, pins or nets.

-to to_list

A list of clocks, instances, ports or pins.

-ignore_clock_latency

Ignore clock latency at the source and target registers.

-probe

Do not break paths at internal pins (non startpoints).

-reset_path

Remove any matching set_false_path, set_multicycle_path, set_max_delay, set_min_delay exceptions first.

delay

The maximum delay.

The set_max_delay command constrains the maximum delay through combinational logic paths. See set_false_path for a description of allowed from_list, through_list and to_list objects. If the to_list ends at a timing check the setup/hold time is included in the path delay.

When the -ignore_clock_latency option is used clock latency at the source and destination of the path delay is ignored. The constraint is reported in the default path group (**default**) rather than the clock path group when the path ends at a timing check.

set_max_dynamic_power

power [unit]

The set_max_dynamic_power command is ignored.

set_max_fanout

fanoutobjects

fanout

objects

List of ports or cells.

The set_max_fanout command is ignored during timing but is included in SDC files that are written.

set_max_leakage_power

power [unit]

The set_max_leakage_power command is ignored.

set_max_time_borrow

delayobjects

delay

The maximum time the latches can borrow.

objects

List of clocks, instances or pins.

The set_max_time_borrow command specifies the maximum amount of time that latches can borrow. Time borrowing is the time that a data input to a transparent latch arrives after the latch opens.

set_max_transition

[-data_path][-clock_path][-rise][-fall]transitionobjects

-data_path

Set the max slew for data paths.

-clock_path

Set the max slew for clock paths.

-rise

Set the max slew for rising paths.

-fall

Set the max slew for falling paths.

transition

The maximum slew/transition time.

objects

List of clocks, ports or designs.

The set_max_transition command is specifies the maximum transition time (slew) design rule checked by the report_check_types –max_transition command.

If specified for a design, the default maximum transition is set for the design.

If specified for a clock, the maximum transition is applied to all pins in the clock domain. The –clock_path option restricts the maximum transition to clocks in clock paths. The -data_path option restricts the maximum transition to clocks data paths. The –clock_path, -data_path, -rise and –fall options only apply to clock objects.

set_min_capacitance

capacitanceobjects

capacitance

Minimum capacitance.

objects

List of ports or cells.

The set_min_capacitance command is ignored during timing but is included in SDC files that are written.

set_min_delay

[-rise][-fall][-from from_list][-rise_from from_list][-fall_from from_list][-through through_list][-rise_through through_list][-fall_through through_list][-to to_list][-rise_to to_list][-fall_to to_list][-ignore_clock_latency][-probe][-reset_path]delay

-rise

Set min delay for rising paths.

-fall

Set min delay for falling paths.

-from from_list

A list of clocks, instances, ports or pins.

-through through_list

A list of instances, pins or nets.

-to to_list

A list of clocks, instances, ports or pins.

-ignore_clock_latency

Ignore clock latency at the source and target registers.

-probe

Do not break paths at internal pins (non startpoints).

-reset_path

Remove any matching set_false_path, set_multicycle_path, set_max_delay, set_min_delay exceptions first.

delay

The minimum delay.

The set_min_delay command constrains the minimum delay through combinational logic. See set_false_path for a description of allowed from_list, through_list and to_list objects. If the to_list ends at a timing check the setup/hold time is included in the path delay.

When the -ignore_clock_latency option is used clock latency at the source and destination of the path delay is ignored. The constraint is reported in the default path group (**default**) rather than the clock path group when the path ends at a timing check.

set_min_pulse_width

[-high][-low]min_widthobjects

-high

Set the minimum high pulse width.

-low

Set the minimum low pulse width.

min_width

objects

List of pins, instances or clocks.

If -low and -high are not specified the minimum width applies to both high and low pulses.

set_mode

mode_name

Set the mode for SDC commands in the TCL interpreter. If mode mode_name does not exist, it is created. When modes are created the default mode is deleted.

set_multicycle_path

[-setup][-hold][-rise][-fall][-start][-end][-from from_list][-rise_from from_list][-fall_from from_list][-through through_list][-rise_through through_list][-fall_through through_list][-to to_list][-rise_to to_list][-fall_to to_list][-reset_path]path_multiplier

-setup

Set cycle count for setup checks.

-hold

Set cycle count for hold checks.

-rise

Set cycle count for rising path edges.

-fall

Set cycle count for falling path edges.

-start

Multiply the source clock period by period_multiplier.

-end

Multiply the target clock period by period_multiplier.

-from from_list

A list of clocks, instances, ports or pins.

-through through_list

A list of instances, pins or nets.

-to to_list

A list of clocks, instances, ports or pins.

-reset_path

Remove any matching set_false_path, set_multicycle_path, set_max_delay, set_min_delay exceptions first.

path_multiplier

The number of clock periods to add to the path required time.

Normally the path between two registers or latches is assumed to take one clock cycle. The set_multicycle_path command overrides this assumption and allows multiple clock cycles for a timing check. See set_false_path for a description of allowed from_list, through_list and to_list objects.

set_operating_conditions

[-analysis_type single|bc_wc|on_chip_variation][-library lib][condition][-min min_condition][-max max_condition][-min_library min_lib][-max_library max_lib]

-analysis_type single

Use one operating condition for min and max paths.

-analysis_type bc_wc

Best case, worst case analysis. Setup checks use max_condition for clock and data paths. Hold checks use the min_condition for clock and data paths.

‑analysis_type on_chip_variation

The min and max operating conditions represent variations on the chip that can occur simultaneously. Setup checks use max_condition for data paths and min_condition for clock paths. Hold checks use min_condition for data paths and max_condition for clock paths. This is the default analysis type.

-library lib

The name of the library that contains condition.

condition

The operating condition for analysis type single.

-min min_condition

The operating condition to use for min paths and hold checks.

-max max_condition

The operating condition to use for max paths and setup checks.

-min_library min_lib

The name of the library that contains min_condition.

-max_library max_lib

The name of the library that contains max_condition.

The set_operating_conditions command is used to specify the type of analysis performed and the operating conditions used to derate library data.

set_output_delay

[-rise][-fall][-max][-min][-clock clock][-clock_fall][-reference_pin ref_pin][-source_latency_included][-network_latency_included][-add_delay]delayport_pin_list

-rise

Set the output delay for the rising edge of the input.

-fall

Set the output delay for the falling edge of the input.

-max

Set the maximum output delay.

-min

Set the minimum output delay.

-clock clock

The external check is to clock. The default clock edge is rising.

-clock_fall

The external check is to the falling edge of clock.

-reference_pin ref_pin

The external check is clocked by the clock that arrives at ref_pin.

-add_delay

Add this output delay to any existing output delays.

delay

The external delay to the check clocked by clock.

pin_port_list

A list of pins or ports.

The set_output_delay command is used to specify the external delay to a setup/hold check on an output port or internal pin that is clocked by clock. Unless the -add_delay option is specified any existing output delays are replaced.

The –reference_pin option is used to specify a timing check with respect to the arrival on a pin in the clock network. For propagated clocks, the timing check is relative to the clock arrival time at the reference pin (the clock source latency and network latency from the clock source to the reference pin). For ideal clocks, the timing check is relative to the reference pin clock source latency. With the -clock_fall flag the timing check is relative to the falling edge of the reference pin. If no clocks arrive at the reference pin the set_output_delay command is ignored. If no -clock is specified the timing check is with respect to all clocks that arrive at the reference pin. The -source_latency_included and -network_latency_included options cannot be used with -reference_pin.

set_port_fanout_number

[-min][-max]fanoutports

-min

Set the min fanout.

-max

Set the max fanout.

fanout

The external fanout of the ports.

port_list

A list of ports.

Set the external fanout for ports.

set_power_activity

[-global][-input][-input_ports ports][-pins pins][-activity activity | -density density][-duty duty][-clock clock]

-global

Set the activity/duty for all non-clock pins.

-input

Set the default input port activity/duty.

-input_ports input_ports

Set the input port activity/duty.

-pins pins

Set the pin activity/duty.

-activity activity

The activity, or number of transitions per clock cycle. If clock is not specified the clock with the minimum period is used. If no clocks are defined an error is reported.

-density density

Transitions per library time unit.

-duty duty

The duty, or probability the signal is high (0 <= duty <= 1.0). Defaults to 0.5.

-clock clock

The clock to use for the period with -activity. This option is ignored if -density is used.

The set_power_activity command is used to set the activity and duty used for power analysis globally or for input ports or pins in the design.

The default input activity for inputs is 0.1 transitions per minimum clock period if a clock is defined or 0.0 if there are no clocks defined. The default input duty is 0.5. This is equivalent to the following command:

set_power_activity -input -activity 0.1 -duty 0.5

set_propagated_clock

objects

objects

A list of clocks, ports or pins.

The set_propagated_clock command changes a clock tree from an ideal network that has no delay one that uses calculated or back-annotated gate and interconnect delays. When objects is a port or pin, clock delays downstream of the object are used.

set_pvt

[-min][-max][-process process][-voltage voltage]

[-temperature temperature]instances

-min

Set the PVT values for max delays.

-max

Set the PVT values for min delays.

-process process

A process value (float).

-voltage voltage

A voltage value (float).

-temperature temperature

A temperature value (float).

instances

A list instances.

The set_pvt command sets the process, voltage and temperature values used during delay calculation for a specific instance in the design.

set_sense

[-type clock|data][-positive][-negative][-pulse pulse_type][-stop_propagation][-clock clocks]pins

-type clock

Set the sense for clock paths.

-type data

Set the sense for data paths (not supported).

-positive

The clock sense is positive unate.

-negative

The clock sense is negative unate.

-pulse pulse_type

rise_triggered_high_pulserise_triggered_low_pulsefall_triggered_high_pulsefall_triggered_low_pulseNot supported.

-stop_propagation

Stop propagating clocks at pins.

clocks

A list of clocks to apply the sense.

pins

A list of pins.

The set_sense command is used to modify the propagation of a clock signal. The clock sense is set with the ‑positive and –negative flags. Use the –stop_propagation flag to stop the clock from propagating beyond a pin. The –positive, -negative, -stop_propagation, and –pulse options are mutually exclusive. If the –clock option is not used the command applies to all clocks that traverse pins. The –pulse option is currently not supported.

set_timing_derate

[-rise][-fall][-early][-late][-clock][-data][-net_delay][-cell_delay][-cell_check]derate[objects]

-rise

Set the derating for rising delays.

-fall

Set the derating for falling delays.

-early

Derate early (min) paths.

-late

Derate late (max) paths.

-clock

Derate paths in the clock network.

-data

Derate data paths.

-net_delay

Derate net (interconnect) delays.

-cell_delay

Derate cell delays.

-cell_check

Derate cell timing check margins.

derate

The derating factor to apply to delays.

objects

A list of instances, library cells, or nets.

The set_timing_derate command is used to derate delay calculation results used by the STA. If the –early and –late flags are omitted the both min and max paths are derated. If the –clock and –data flags are not used the derating both clock and data paths are derated.

Use the unset_timing_derate command to remove all derating factors.

set_resistance

[-max][-min]resistancenets

-min

The resistance for minimum path delay calculation.

-max

The resistance for maximum path delay calculation.

resistance

The net resistance.

nets

A list of nets.

set_units

[-capacitance cap_unit][-resistance res_unit][-time time_unit][-voltage voltage_unit][-current current_unit][-power power_unit][-distance distance_unit]

-capacitance cap_unit

The capacitance scale factor followed by 'f'.

-resistance res_unit

The resistance scale factor followed by 'ohm'.

-time time_unit

The time scale factor followed by 's'.

-voltage voltage_unit

The voltage scale factor followed by 'v'.

-current current_unit

The current scale factor followed by 'A'.

-power power_unit

The power scale factor followed by 'w'.

The set_units command is used to check the units used by the STA command interpreter when parsing commands and reporting results. If the current units differ from the set_unit value a warning is printed. Use the set_cmd_units command to change the command units.

Units are specified as a scale factor followed by a unit name. The scale factors are as follows.

M 1E+6k 1E+3m 1E-3u 1E-6n 1E-9p 1E-12f 1E-15

An example of the set_units command is shown below.

set_units -time ns -capacitance pF -current mA -voltage V -resistance kOhm

set_wire_load_min_block_size

size

The set_wire_load_min_block_size command is not supported.

set_wire_load_mode

top|enclosed|segmented

top

enclosed

segmented

The set_wire_load_mode command is ignored during timing but is included in SDC files that are written.

set_wire_load_model

-name model_name[-library library][-max][-min][objects]

-name model_name

The name of a wire load model.

-library library

Library to look for model_name.

-max

The wire load model is for maximum path delays.

-min

The wire load model is for minimum path delays.

objects

Not supported.

set_wire_load_selection_group

[-library library][-max][-min]group_name[objects]

library

Library to look for group_name.

-max

The wire load selection is for maximum path delays.

-min

The wire load selection is for minimum path delays.

group_name

A wire load selection group name.

objects

Not supported.

The set_wire_load_selection_group command is parsed but not supported.

suppress_msg

msg_ids

msg_ids

A list of error/warning message IDs to suppress.

The suppress_msg command suppresses specified error/warning messages by ID. The list of message IDs can be found in doc/messages.txt.

unset_case_analysis

port_or_pin_list

port_or_pin_list

A list of ports or pins.

The unset_case_analysis command removes the constant values defined by the set_case_analysis command.

unset_clock_latency

[-source]objects

-source

Specifies source clock latency (clock insertion delay).

objects

A list of clocks, pins or ports.

The unset_clock_latency command removes the clock latency set with the set_clock_latency command.

unset_clock_transition

clocks

clocks

A list of clocks.

The unset_clock_transition command removes the clock transition set with the set_clock_transition command.

unset_clock_uncertainty

[-from|-rise_from|-fall_from from_clock][-to|-rise_to|-fall_to to_clock][-rise][-fall][-setup][-hold][objects]

-from from_clock

-to to_clock

-rise

The uncertainty is for the rising edge of the clock.

-fall

The uncertainty is for the falling edge of the clock.

-setup

uncertainty is the setup check uncertainty.

-hold

uncertainty is the hold uncertainty.

uncertainty

Clock uncertainty.

objects

A list of clocks, ports or pins.

The unset_clock_uncertainty command removes clock uncertainty defined with the set_clock_uncertainty command.

unset_data_check

[-from|-rise_from|-fall_from from_object][-to|-rise_to|-fall_to to_object][-setup][-hold][-clock clock]

-from from_object

A pin used as the timing check reference.

-to to_object

A pin that the setup/hold check is applied to.

-setup

Add a setup timing check.

-hold

Add a hold timing check.

clock

The setup/hold check clock.

The unset_clock_transition command removes a setup or hold check defined by the set_data_check command.

unset_disable_inferred_clock_gating

objects

objects

A list of clock gating instances, clock gating pins, or clock enable pins.

The unset_disable_inferred_clock_gating command removes a previous set_disable_inferred_clock_gating command.

unset_disable_timing

[-from from_port][-to to_port]objects

from_port

to_port

objects

A list of instances, ports, pins, cells or [library/]cell/port.

The unset_disable_timing command is used to remove the effect of previous set_disable_timing commands.

unset_input_delay

[-rise][-fall][-max][-min][-clock clock][-clock_fall]port_pin_list

-rise

Unset the arrival time for the rising edge of the input.

-fall

Unset the arrival time for the falling edge of the input.

-max

Unset the minimum arrival time.

-min

Unset the maximum arrival time.

clock

Unset the arrival time from clock.

-clock_fall

Unset the arrival time from the falling edge of clock

pin_port_list

A list of pins or ports.

The unset_input_delay command removes a previously defined set_input_delay.

unset_output_delay

[-rise][-fall][-max][-min][-clock clock][-clock_fall]port_pin_list

-rise

This is the arrival time for the rising edge of the input.

-fall

This is the arrival time for the falling edge of the input.

-max

This is the minimum arrival time.

-min

This is the maximum arrival time.

clock

The arrival time is from this clock.

-clock_fall

The arrival time is from the falling edge of clock

pin_port_list

A list of pins or ports.

The unset_output_delay command a previously defined set_output_delay.

unset_path_exceptions

[-setup][-hold][-rise][-fall][-from|-rise_from|-fall_from from][-through|-rise_through|-fall_through through][-to|-rise_to|-fall_to to]

-setup

Unset path exceptions for setup checks.

-hold

Unset path exceptions for hold checks.

-rise

Unset path exceptions for rising path edges.

-fall

Unset path exceptions for falling path edges.

-from from

A list of clocks, instances, ports or pins.

-through through

A list of instances, pins or nets.

-to to

A list of clocks, instances, ports or pins.

The unset_path_exceptions command removes any matching set_false_path, set_multicycle_path, set_max_delay, and set_min_delay exceptions.

unset_power_activity

[-global][-input][-input_ports ports][-pins pins]

-global

Set the activity/duty for all non-clock pins.

-input

Set the default input port activity/duty.

-input_ports input_ports

Set the input port activity/duty.

-pins pins

Set the pin activity/duty.

-activity activity

The activity, or number of transitions per clock cycle. If clock is not specified the clock with the minimum period is used. If no clocks are defined an error is reported.

The unset_power_activity_command is used to undo the effects of the set_power_activity command.

unset_propagated_clock

objects

objects

A list of clocks, ports or pins.

Remove a previous set_propagated_clock command.

unset_timing_derate

Remove all derating factors set with the set_timing_derate command.

unsuppress_msg

msg_ids

msg_ids

A list of error/warning message IDs to unsuppress.

The unsuppress_msg command removes suppressions for the specified error/warning messages by ID. The list of message IDs can be found in doc/messages.txt.

user_run_time

Returns the total user cpu run time in seconds as a float.

with_output_to_variable

var { commands }

var

The name of a variable to save the output of commands to.

commands

TCL commands that the output will be redirected from.

The with_output_to_variable command redirects the output of TCL commands to a variable.

write_path_spice

-path_args path_args-spice_file spice_file-lib_subckt_file lib_subckts_file-model_file model_file-power power-ground ground[-simulator hspice|ngspice|xyce]

path_args

-from|-through|-to arguments as in report_checks.

spice_file

Directory and path prefix for spice output files.

lib_subckts_file

Cell transistor level subckts.

model_file

Transistor model definitions .included by spice_file.

power

Voltage supply name in voltage_map of the default liberty library.

ground

Ground supply name in voltage_map of the default liberty library.

-simulator

Simulator that will read the spice netlist.

The write_path_spice command writes a spice netlist for timing paths. Use path_args to specify -from/-through/-to as arguments to the find_timing_paths command. For each path, a spice netlist and the subckts referenced by the path are written in spice_directory. The spice netlist is written in path_<id>.sp and subckt file is path_<id>.subckt.

The spice netlists used by the path are written to subckt_file, which spice_file .includes. The device models used by the spice subckt netlists in model_file are also .included in spice_file. Power and ground names are specified with the -power and -ground arguments. The spice netlist includes a piecewise linear voltage source at the input and .measure statement for each gate delay and pin slew.

Example command:

write_path_spice -path_args {-from "in0" -to "out1" -unconstrained} \ -spice_directory $result_dir \ -lib_subckt_file "write_spice1.subckt" \ -model_file "write_spice1.models" \ -power VDD -ground VSS

When the simulator is hspice, .measure statements will be added to the spice netlist.

When the simulator is Xyce, the .print statement selects the CSV format and writes the waveform data to a file name path_<id>.csv so the results can be used by gnuplot.

write_sdc

[-digits digits][-gzip][-no_timestamp]filename

digits

The number of digits after the decimal point to report. The default is 4.

-gzip

Compress the SDC with gzip.

-no_timestamp

Do not include a time and date in the SDC file.

filename

The name of the file to write the constraints to.

Write the constraints for the design in SDC format to filename.

write_sdf

[-scene scene][-divider /|.][-include_typ][-digits digits][-gzip][-no_timestamp][-no_version]filename

scene

Write delays for scene.

-divider

Divider to use between hierarchy levels in pin and instance names.

-include_typ

Include a 'typ' value in the SDF triple that is the average of min and max delays to satisfy some Verilog simulators that require three values in the delay triples.

-digits digits

The number of digits after the decimal point to report. The default is 4.

-gzip

Compress the SDF using gzip.

-no_timestamp

Do not write a DATE statement.

-no_version

Do not write a VERSION statement.

filename

The SDF filename to write.

Write the delay calculation delays for the design in SDF format to filename. If -corner is not specified the min/max delays are across all corners. With -corner the min/max delays for corner are written. The SDF TIMESCALE is same as the time_unit in the first liberty file read.

write_timing_model

[-library_name lib_name][-cell_name cell_name]

[-scene scene]filename

lib_name

The name to use for the liberty library. Defaults to cell_name.

cell_name

The name to use for the liberty cell. Defaults to the top level module name.

scene

The scene to use for extracting the model.

filename

Filename for the liberty timing model.

The write_timing_model command constructs a liberty timing model for the current design and writes it to filename. cell_name defaults to the cell name of the top level block in the design.

The SDC used to extract the block should include the clock definitions. If the block contains a clock network set_propagated_clock should be used so the clock delays are included in the timing model. The following SDC commands are ignored when building the timing model.

set_input_delayset_output_delayset_loadset_timing_derate

Using set_input_transition with the slew from the block context will be used will improve the match between the timing model and the block netlist. Paths defined on clocks that are defined on internal pins are ignored because the model has no way to include the clock definition.

The resulting timing model can be used in a hierarchical timing flow as a replacement for the block to speed up timing analysis. This hierarchical timing methodology does not handle timing exceptions that originate or terminate inside the block. The timing model includes:

combinational paths between inputs and outputssetup and hold timing constraints on inputsclock to output timing paths

Resistance of long wires on inputs and outputs of the block cannot be modeled in Liberty. To reduce inaccuracies from wire resistance in technologies with resistive wires place buffers on inputs and ouputs.

The extracted timing model setup/hold checks are scalar (no input slew dependence). Delay timing arcs are load dependent but do not include input slew dependency.

write_verilog

[-include_pwr_gnd][-remove_cells lib_cells]filename

-include_pwr_gnd

Include power and ground pins on instances.

-remove_cells lib_cells

Liberty cells to remove from the Verilog netlist. Use get_lib_cells, a list of cells names, or a cell name with wildcards.

filename

Filename for the liberty library.

The write_verilog command writes a Verilog netlist to filename. Use -sort to sort the instances so the results are reproducible across operating systems. Use -remove_cells to remove instances of lib_cells from the netlist.

Filter Expressions

The get_cells, get_pins, get_ports and get_timing_edges functions support filtering the returned objects by property values. Supported filter expressions are shown below.

property

Return objects with property value equal to 1.

property==value

Return objects with property value equal to value.

property=~pattern

Return objects with property value that matches pattern.

property!=value

Return objects with property value not equal to value.

property!~value

Return objects with property value that does not match pattern.

expr1&&expr2

Return objects with expr1 and expr2. expr1 and expr2 are one of the first three property value forms shown above.

expr1||expr2

Return objects with expr1 or expr2. expr1 and expr2 are one of the first three property value forms shown above.

Where property is a property supported by the get_property command. Note that if there are spaces in the expression it must be enclosed in quotes so that it is a single argument.

Variables

hierarchy_separator

Any character.

The hierarchy_separator separates instance names in a hierarchical instance, net, or pin name. The default value is '/'.

sta_continue_on_error

0|1

The include and read_sdc commands stop and report any errors encountered while reading a file unless sta_continue_on_error is 1. The default value is 0.

sta_crpr_mode

same_pin|same_transition

When the data and clock paths of a timing check overlap (see sta_crpr_enabled), pessimism is removed independent of whether of the path rise/fall transitions. When sta_crpr_mode is same_transition, the pessimism is only removed if the path rise/fall transitions are the same. The default value is same_pin.

sta_cond_default_arcs_enabled

0|1

When set to 0, default timing arcs with no condition (Liberty timing arcs with no “when” expression) are disabled if there are other conditional timing arcs between the same pins. The default value is 1.

sta_crpr_enabled

0|1

During min/max timing analysis for on_chip_variation the data and clock paths may overlap. For a setup check the maximum path delays are used for the data and the minimum path delays are used for the clock. Because the gates cannot simultaneously have minimum and maximum delays the timing check slack is pessimistic. This pessimism is known as Common Reconvergent Pessimism Removal, or “CRPR”. Enabling CRPR slows down the analysis. The default value is 1.

sta_dynamic_loop_breaking

0|1

When sta_dynamic_loop_breaking is 0, combinational logic loops are disabled by disabling a timing arc that closes the loop. When sta_dynamic_loop_breaking is 1, all paths around the loop are reported. The default value is 0.

sta_gated_clock_checks_enabled

0|1

When sta_gated_clock_checks_enabled is 1, clock gating setup and hold timing checks are checked. The default value is 1.

sta_input_port_default_clock

0|1

When sta_input_port_default_clock is 1 a default input arrival is added for input ports that do not have an arrival time specified with the set_input_delay command. The default value is 0.

sta_internal_bidirect_instance_paths_enabled

0|1

When set to 0, paths from bidirectional (inout) ports back into the instance are disabled. When set to 1, paths from bidirectional ports back into the instance are enabled. The default value is 0.

sta_pocv_mode

scalar|normal|skew_normal

Enable parametric on chip variation using statistical timing analysis. The default value is scalar.

sta_pocv_quartile

quartile

The target quantile of a delay probability distribution (confidence level).The default value is 3 standard deviations, or sigma.

sta_propagate_all_clocks

0|1

All clocks defined after sta_propagate_all_clocks is set to 1 are propagated. If it is set before any clocks are defined it has the same effect as

set_propagated_clock [all_clocks]

After all clocks have been defined. The default value is 0.

sta_propagate_gated_clock_enable

0|1

When set to 1, paths of gated clock enables are propagated through the clock gating instances. If the gated clock controls sequential elements setting sta_propagate_gated_clock_enable to 0 prevents spurious paths from the clock enable. The default value is 1.

sta_recovery_removal_checks_enabled

0|1

When sta_recovery_removal_checks_enabled is 0, recovery and removal timing checks are disabled. The default value is 1.

sta_report_default_digits

integer

The number of digits to print after a decimal point. The default value is 2.

sta_preset_clear_arcs_enabled

0|1

When set to 1, paths through asynchronous preset and clear timing arcs are searched. The default value is 0.

Alphabetical Index

Alphabetical Index

all_clocks7

all_inputs7

all_outputs8

all_registers8

check_setup9

Command Line Arguments1

Commands7

connect_pin9

create_generated_clock11

create_voltage_area12

current_design12

current_instance13

define_scene13

delete_clock13

delete_from_list13

delete_generated_clock14

delete_instance14

delete_net14

disconnect_pin14

elapsed_run_time14

Example Command Scripts1

Filter Expressions84

find_timing_paths15

get_cells17

get_clocks17

get_fanin18

get_fanout19

get_full_name19

get_lib_pins20

get_libs21

get_name22

get_nets22

get_pins23

get_ports23

get_property24

get_scenes28

get_timing_edges28

group_path29

hierarchy_separator85

include30

link_design30

make_instance30

make_net31

Power Analysis3

read_liberty31

read_saif32

read_sdc33

read_sdf33

read_spef34

read_vcd35

read_verilog35

redirection5

replace_activity_annotation36

replace_cell35

report_annotated_check36

report_annotated_delay37

report_check_types41

report_checks38

report_clock_latency42

report_clock_min_period42

report_clock_properties43

report_clock_skew43

report_dcalc43

report_disabled_edges44

report_edges44

report_instance44

report_lib_cell44

report_net45

report_parasitic_annotation45

report_power45

report_slews46

report_tns46

report_units46

report_wns47

report_worst_slack47

set_assigned_check48

set_assigned_delay49

set_assigned_transition49

set_case_analysis50

set_clock_gating_check50

set_clock_groups51

set_clock_latency52

set_clock_transition52

set_clock_uncertainty53

set_cmd_units54

set_data_check55

set_disable_inferred_clock_gating55

set_disable_timing55

set_drive56

set_driving_cell57

set_false_path58

set_fanout_load59

set_hierarchy_separator59

set_ideal_latency59

set_ideal_network59

set_ideal_transition59

set_input_delay59

set_input_transition61

set_level_shifter_strategy61

set_level_shifter_threshold61

set_load61

set_logic_dc62

set_logic_one62

set_logic_zero63

set_max_area63

set_max_capacitance63

set_max_delay63

set_max_dynamic_power64

set_max_fanout64

set_max_leakage_power64

set_max_time_borrow64

set_max_transition65

set_min_capacitance65

set_min_delay66

set_min_pulse_width67

set_mode67

set_multicycle_path67

set_operating_conditions68

set_output_delay69

set_port_fanout_number70

set_power_activity70

set_propagated_clock71

set_pvt71

set_resistance73

set_sense72

set_timing_derate73

set_units74

set_wire_load_min_block_size75

set_wire_load_mode75

set_wire_load_model75

set_wire_load_selection_group75

SPEF34

sta_cond_default_arcs_enabled85

sta_continue_on_error85

sta_crpr_enabled85

sta_crpr_mode85

sta_dynamic_loop_breaking85

sta_gated_clock_checks_enabled85

sta_input_port_default_clock86

sta_internal_bidirect_instance_paths_enabled86

sta_pocv_enabled86

sta_preset_clear_arcs_enabled87

sta_propagate_all_clocks86

sta_propagate_gated_clock_enable86

sta_recovery_removal_checks_enabled86

sta_report_default_digits86

suppress_msg76

TCL Interpreter5

Timing Analysis using SDF2

Timing Analysis with Multiple Corners and Modes3

Timing Analysis with Multiple Process Corners2

unset_case_analysis76

unset_clock_latency76

unset_clock_transition76

unset_clock_uncertainty77

unset_data_check77

unset_disable_inferred_clock_gating78

unset_disable_timing78

unset_input_delay78

unset_output_delay79

unset_path_exceptions79

unset_power_activity80

unset_propagated_clock80

unset_timing_derate80

unsuppress_msg81

user_run_time81

Variables85

verilog netlist35

with_output_to_variable81

write_path_spice81

write_sdc82

write_sdf82

write_timing_model83

write_verilog84

Version 3.0.0, Mar 7, 2026Copyright (c) 2026, Parallax Software, Inc.

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>.