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Visible to Intel only — GUID: mtr1422491990782
Ixiasoft
Visible to Intel only — GUID: mtr1422491990782
Ixiasoft
4.3.1.5. KEEP
The following example shows how both VHDL and Verilog HDL set the equivalent KEEP constraint (Differential SSTL-2 Class I) to the my_wire signal.
Verilog HDL example in the Vivado* software:
(* KEEP = "TRUE" *) wire my_wire
Equivalent Verilog HDL example in the Intel® Quartus® Prime software:
( *preserve*) wire my_wire;
VHDL example in the Vivado* software:
signal my_wire: bit;
attribute keep: string;
attribute keep of my_wire: signal is "TRUE";
Equivalent VHDL example in the Intel® Quartus® Prime software:
signal my_wire: bit;
attribute syn_keep: boolean;
attribute syn_keep of my_wire: signal is true;