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AR# 3679

FPGA Express 2.0/Synopsys: RISING_EDGE vhdl syntax not supported. (VHDL-2204)

Description

Keywords: RISING, EDGE, vhdl, syntax, 2204, Express, Synopsys

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

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.
AR# 3679
Date Created 03/23/1998
Last Updated 09/03/1999
Status Archive
Type General Article