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Verilog processes

Verilog and SystemVerilog always constructs without an event control statement at the top cannot be synthesized. Additionally, they would activate in random order at the moment 0 at the beginning of a simulation.

Sigasi warns about always blocks without an event control statement at the start.

A good way to correct this description is to place the timing control statement at the top.

VERILOG
module test(clk, data_in, data_out);
    input clk;
    input[3:0] data_in;
    output reg[3:0] data_out;

    always
    begin
        data_out <= data_in;
        @(posedge clk); // Timing control not at the top of 'always'
    end
endmodule

module test(clk, data_in, data_out);
    input clk;
    input[3:0] data_in;
    output reg[3:0] data_out;

    always @(posedge clk)
       data_out <= data_in;

endmodule

Rule configuration

This rule can be disabled for your project, or its severity and parameters can be modified in the project linting settings. Alternatively, it can be manually configured using one of the following templates, depending on the type of project you use.

  • For Modular Projects, add these entries to your project's .sigasi/settings.json settings file. To scope the settings to a specific folder or file instead of the whole project, place them inside an @override block; to scope them to a specific target, place them inside a @targets block.

    JSONC
    {
        "verilog.rules.27.severity": "{ERROR|WARNING|INFO|IGNORE}"
    }
  • For Classic Projects, add the VHDL lines to .settings/com.sigasi.hdt.vhdl.linting.prefs and the Verilog/SystemVerilog lines to .settings/com.sigasi.hdt.verilog.linting.prefs:

    PREFS
    27/severity/${path}={error|warning|info|ignore}