#SYNPLIFY PRO STOP CLOCK INFERENCE HOW TO#
#SYNPLIFY PRO STOP CLOCK INFERENCE MANUAL#
#SYNPLIFY PRO STOP CLOCK INFERENCE FULL#
#SYNPLIFY PRO STOP CLOCK INFERENCE VERIFICATION#
#SYNPLIFY PRO STOP CLOCK INFERENCE SOFTWARE#

#SYNPLIFY PRO STOP CLOCK INFERENCE FULL#

The synthesis compiler will create a synthesis report clock summary with information on inferred clocks that you can use for identifying, defining and constraining clocks.ДЇourth, run a full вЂconstraints checkвЂ™. In the Synplify Premier synthesis software, you can do this using the following command: Fast synthesis allows you to perform a clock setup check, because it generates both a clock report and a timing report that make clock setup issues apparent.Д¬ertain synthesis tools enable you to run synthesis in a вЂfastвЂ™ mode, which disables some synthesis optimisations in the interest of rapid run-time. Third, run basic вЂfast synthesisвЂ™ that checks for clock setup issues, including declared, derived and inferred clocks. These errors are reported in a separate log file. Second, run a вЂsynthesis checkвЂ™ to detect hardware-related errors such as incorrectly coded flip-flops.

#SYNPLIFY PRO STOP CLOCK INFERENCE MANUAL#

The errors will appear in a log file that can be hyperlinked back to the error manual that explains the error and suggests a fix. The constraints will be forward-annotated to the Vivado place-and-route tool.ДЇirst run a вЂsyntax checkвЂ™ вЂ“ that is, a quick check of constraints, including their embedded get_XX and all_XX commands, to uncover and clean up any constraint syntax errors.

#SYNPLIFY PRO STOP CLOCK INFERENCE SOFTWARE#

To give you an idea of the types of constraints checks that are worthwhile, letвЂ™s look at the checks that Synplify software performs.ДЇigure 1 above shows an initial Synplify synthesis input constraints file takes care of basic clock setup and I/O constraints requirements.

#SYNPLIFY PRO STOP CLOCK INFERENCE VERIFICATION#

We recommend four constraints verification techniques during the design setup phase. Hint: In Vivado Design Suite, clock constraints should be applied as close to the source clock as possible, not on the BUFG, as was the case in Xilinx ISE Design Suite flows.

Define timing exceptions such as false paths and multicycle paths.

Provide correct clock constraints вЂ“ donвЂ™t over-constrain, and be sure to place unrelated (aka asynchronous) clocks in separate clock groups.

Define clocks on the black box output pins.

Define all primary clocks on input ports or nets connected to input ports.

When setting up constraints in Vivado Design Suite flows, be sure to do the following: In this example, you can see that key items, such as declaring clocks, clock group (relationship between clocks) and input/output delays, have been taken care of. Since constraints setup can be daunting, the synthesis software can help by providing an initial constraints template with basic constraints and syntax that can act as a starting point.ДЇor example, in the Synplify synthesis software, run the TCL utility to create an initial FDC file for a specific design:ДЇigure 1В ( right) shows an example of the constraints (.fdc) file that this process will generate. It is important to be sure to specify multicycle and false paths, and to set constraints on derived clocks: Over-constraining will result in longer run times and potentially, the reporting of false critical paths. You will want to check that you have adequately and completely constrained your design, without having over-constrained it.

Define multicycle paths and false paths.

Identify and create clock groupings and clock relationships.

The synthesis tool can assist with the challenging task of setting up presynthesis constraints.

Once the design has been synthesised, these constraints and the critical path information will automatically be forward-annotated to the Vivado Design Suite place-and-route tools to further ensure that timing will be met. The constraints communicate your design intent and the designвЂ™s performance goals to the synthesis tool. The biggest bang for your buck will come from specifying correct and complete design constraints.

#SYNPLIFY PRO STOP CLOCK INFERENCE HOW TO#

It is worth taking a closer look at some of these techniques in all three categories, and considering how to use them to achieve your timing goals. Correlation of synthesis and place-and-route timing to deliver better timing quality-of-results (QoR) and timing closure.Time-saving design techniques such as careful RTL coding for better performance results and grouping together the parts of the design that pose the greatest performance challenge, to reduce iteration run times when you later tune the design.Better design setup, such as complete and accurate timing constraints and clock specifications.

There are multiple angles of attack, including: Designers now have access to certain tips and tricks that will help them set up clocks, correctly set timing constraints using tools like Synopsys Synplify Premier, and then fine tune parameters to meet the performance goals of the Xilinx FPGA design.

Synplify pro stop clock inference