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AR# 18974

6.2i XST - "ERROR:Xst:1548 - file.vhd line xx: Negative range in type of signal <h> is not supported"


Keywords: std_logic_vector, real

Urgency: Standard

General Description:
In designs that use real type functions, XST incorrectly synthesizes the design and issues the following error message:

"ERROR:Xst:1548 - file.vhd line xx: Negative range in type of signal <h> is not supported."



For real type functions, this problem has been fixed in the latest 6.2i Service Pack, available at:
The first service pack containing the fix is 6.2i Service Pack 1.


If you are not using real data types in your design, then the XST error message is correct because negative ranges are not supported.
AR# 18974
Date Created 02/17/2004
Last Updated 07/18/2007
Status Archive
Type General Article