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AR# 20148

6.2i ECS - "ERROR:HDLParsers:816 - <file_name>.vhf Line <##>. Attribute KEEP. Two specifications for entity <inst_name>"


Keywords: ECS, attribute, property, internal, twice, functional model, .vf, VF, .vhf, VHF

Urgency: Standard

General Description:
Customer applies KEEP constraint (or other internal constraint) on a net going from one module to another, and it gets produced twice in ".vhf" functional model. This causes XST to fail with the following error:

"ERROR:HDLParsers:816 - <file_name>.vhf Line <line number>. Attribute KEEP. Two specifications for entity <inst_name>"

Attributes are correctly written out for nets going from IOmarker to a module, but not when placed on nets going from one module to another.


The attribute needs to be written out only once to avoid this error in XST. To work around this issue, manually edit the ".vf" file every time after updating the schematic.

This problem has been fixed in the latest 6.3i Service Pack available at:
The first service pack containing the fix is 6.3i Service Pack 2.
AR# 20148
Date Created 10/11/2004
Last Updated 01/08/2006
Status Archive
Type General Article