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AR# 13922

4.1isp3 MAP - "ERROR:Pack:625 - The dual data rate register "x" failed to combine with output buffer "y" as required..."


Keywords: IOB, pack, 625, 626, DDR, pack, SR, reset, flop, GND, ground

Urgency: Standard

General Description:
When I attempt to use either output DDR primitive (FDDRCPE, FDDRRSE) and wish to only connect one set of flip-flops to a reset (leaving the other unconnected), MAP issues the following errors:

"ERROR:Pack:625 - The dual data rate register XLXI_26 failed to combine with output buffer XLXI_19 as required. Register XLXI_26 set/reset disagrees with another register in the I/O component."

"ERROR:Pack:626 - The dual data rate register XLXI_26 failed to join an I/O component as required. Please try constraining the register together with a valid pad or output buffer symbol. Note that FDDR library symbols may drive output buffers only."


MAP is incorrectly detecting a conflict for the reset resource between an FF with reset used and an FF with unused (or GND'd) reset.

This problem is fixed in the latest 4.2i Service Pack, available at:
The first service pack containing the fix is 4.2i Service Pack 2.
AR# 13922
Date Created 02/21/2002
Last Updated 08/20/2003
Status Archive
Type General Article