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AR# 24914

9.1i XST - "ERROR - Xst_HdlConst_Utility::BitVector2Const: invalid type (char)"

Description

When synthesizing a generic port with "character" type such as the entity below, XST 9.1i generates the following error:

"ERROR:Xst - Xst_HdlConst_Utility::BitVector2Const : invalid type (char).

Analyzing hierarchy for entity <chartest> in library <work> (architecture <testcase>) with generics.

TERMCHAR = no-value

ERROR:Xst:2434 - "C:/cases/674933/chartest/chartest/chartest.vhdl" line 9: Generic <TERMCHAR> has not been given a value."

Entity

entity test is

generic (

MY_CHAR : character := cr);

port (

clk : in std_logic; -- clock

rst_l : in std_logic; -- reset

din : in std_logic_vector(7 downto 0); -- data in

end : out std_logic);

end entity test;

Solution

This issue is related to a build hierarchy feature added in XST 8.2i. When checking hierarchy consistency, XST incorrectly rejects when the port type is record and when the record has an element that is boolean, enum, or character type.

To work around this issue, use a non-record type (bit for example) or use a constant:

architecture testcase of test is

constant MY_CHAR: character:= cr;

This issue is fixed in ISE 9.2i.

AR# 24914
Date Created 09/04/2007
Last Updated 12/15/2012
Status Active
Type General Article