Answers Database FPGA Express 2.0/Synopsys: RISING_EDGE vhdl syntax not supported. (VHDL-2204) Record #3679 Product Family: Software Product Line: Synopsys Product Part: FPGA Express Product Version: 2.0 Problem Title: FPGA Express 2.0/Synopsys: RISING_EDGE vhdl syntax not supported. (VHDL-2204) Problem Description: Urgency: Standard General Description: When the syntax "RISING_EDGE" is used within a VHDL design analyzed by FPGA Express 1.x or 2.0.x, the following error will occur: Error: Could not find object subprogram RISING_EDGE. This error can occur if a package (World) that exists in memory also exists in another library referred to in a Library statement. This error can also occur if the package uses synthesis_off/synthesis_on directives around the object. (VHDL-2204) Solution 1: RISING_EDGE is not supported by FPGA Express 1.x or 2.0.x. RISING_EDGE(CLK) should be replaced by (CLK'event and CLK='1') RISING_EDGE is supported by FPGA Express 2.1.x and newer. End of Record #3679 - Last Modified: 09/03/99 13:51

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