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AR# 7425

4.1i NGDBuild - The INIT value applied to RAM/ROM via the UCF is handled incorrectly


Keywords: NGDBuild, INIT, UCF, ROM, RAM

Urgency: Standard

General Description:
When I have RAM/ROM INIT strings in my UCF file, the INIT values are not pushed down to the simulation models. As a result, the simulation behavior is incorrect. How can I work around this issue?

NOTE: This problem should only occur for NGD simulation. MAP and down-stream tools should get the correct values.


To work around this problem, either back-annotate without the NGM, or put the INIT values in the NCF file.

Using an NCF file instead may fix this problem. The NCF file is not the same as the UCF file and has different scoping rules.

The INIT values can also be applied in the HDL.

This will be fixed in version 6.1i of the Xilinx ISE software.
AR# 7425
Date Created 08/31/1999
Last Updated 08/12/2003
Status Archive
Type General Article