Intel® Quartus® Prime Pro Edition User Guide: Scripting

ID 683432
Date 10/04/2021
Public

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3.1.29.43. report_asynch_cdc (::quartus::sta)

The following table displays information for the report_asynch_cdc Tcl command:

Tcl Package and Version

Belongs to ::quartus::sta

Syntax report_asynch_cdc [-h | -help] [-long_help] [-append] [-detail <summary|full> ] [-fall_from_clock <names> ] [-fall_to_clock <names> ] [-file <name> ] [-from <names> ] [-from_clock <names> ] [-intra_clock] [-multi_bit_cdc] [-nentries <number> ] [-panel_name <name> ] [-reset_cdc] [-rise_from_clock <names> ] [-rise_to_clock <names> ] [-single_bit_cdc] [-stdout] [-to <names> ] [-to_clock <names> ]
Arguments -h | -help Short help
-long_help Long help with examples and possible return values
-append If output is sent to a file, this option appends the result to that file. Otherwise, the file will be overwritten. This option is not supported for HTML files.
-detail <summary|full> Option to specify how much detail should be shown in the CDC report
-fall_from_clock <names> Valid source clocks (string patterns are matched using Tcl string matching)
-fall_to_clock <names> Valid destination clocks (string patterns are matched using Tcl string matching)
-file <name> Sends the results to an ASCII or HTML file. Depending on the extension
-from <names> Valid sources (string patterns are matched using Tcl string matching)
-from_clock <names> Valid source clocks (string patterns are matched using Tcl string matching)
-intra_clock Only report paths whose launch and latch clock are the same
-multi_bit_cdc Report multi-bit CDC topologies found in the design
-nentries <number> Display up to this number of entries per CDC topology. Only applicable in full detail mode
-panel_name <name> Sends the results to the panel and specifies the name of the new panel
-reset_cdc Report reset CDC topologies found in the design
-rise_from_clock <names> Valid source clocks (string patterns are matched using Tcl string matching)
-rise_to_clock <names> Valid destination clocks (string patterns are matched using Tcl string matching)
-single_bit_cdc Report single-bit CDC topologies found in the design
-stdout Send output to stdout, via messages. You only need to use this option if you have selected another output format, such as a file, and would also like to receive messages.
-to <names> Valid destinations (string patterns are matched using Tcl string matching)
-to_clock <names> Valid destination clocks (string patterns are matched using Tcl string matching)
Description

This report displays all Clock-Domain-Crossings (CDC) between asynchronous clocks in a design. The report can be directed to the Tcl console ("-stdout", default), a file ("-file"), the Timing Analyzer graphical user interface ("-panel_name"), or any combination of the three. By default, this command reports all CDC's in a design. You can limit the analysis performed by this command to specific CDC source and destination nodes, using the "-from" and "-to" options. The analysis can also be limited using clocks. Specify the CDC's source and destination clocks using the "-from_clock" and "-to_clock" options. Alternatively, specify edges of the clock using "-rise_from_clock", "-fall_from_clock", "-rise_to_clock", and "-fall_to_clock" options. To limit the report to only display specific categories of CDC's, use "-multi_bit_cdc" to report multi-bit CDC buses, "-single_bit_cdc" to report single-bit CDC synchronizers, and "-reset_cdc" to report asynchronous reset topologies. By default, all three CDC categories are reported. Use the "-nentries" option to limit the number of CDC's displayed per CDC topology type. The topology types fall into one of the three categories above. Run the report to see all the topology types that are supported. Use the "-detail" option to specify the desired level of reporting detail. "summary" generates a table listing only the number of CDC topologies recognized per category and the total number of crossings for that category. "full" reports every recognized CDC under each topology type, and is the default behaviour. In the full report, you can click on each individual CDC in the Timing Analyzer graphical user interface to view its statistics.

Example Usage
# Report all bus CDC's, up to 10 buses per CDC topology type
report_asynch_cdc -buses -nentries 10

# Report all CDC's from clkA to clkB
report_asynch_cdc -from_clock clkA -to_clock clkB

# Report all synchronizer chains whose source node contains "transfer"
report_asynch_cdc -from *transfer* -synch_chains
Return Value Code Name Code String Return
TCL_OK 0 INFO: Operation successful
TCL_ERROR 1 ERROR: The current report cannot be run in XML mode. Use create_timing_netlist to create a non-XML timing netlist.