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AR# 13346

4.1i Virtex-II MAP - DPRAM RPM that worked in 3.1i is not placeable in 4.1i


Keywords: LUT, DPRAM, RPM, relative placement, ERROR:Place:1849

Urgency: Standard

General Description:
A DPRAM RPM that worked in 3.1i is un-placable in 4.1i -- PAR quits in the placer with the following error:

"ERROR:Place:1849 - Relative placement of ram SLICE N_SP<2> in rpm U1/hset cannot be placed such that it is routable. This component is the write half of the pair and may not be paired with SLICE data<3>, which is placed 2 slices above it where the read half must exist. Please correct the relative placement problem if possible."


The failure occurs because MAP is swapping the position of 2 LUTs within one of the slices.

This problem is fixed in the latest 4.1i Service Pack, available at:
The first service pack containing the fix is 4.1i Service Pack 3.
AR# 13346
Date Created 12/06/2001
Last Updated 08/20/2003
Status Archive
Type General Article