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AR# 21213

Synplify 8.0 - Synplify combines unlike registers (FDSE, FDRE)


Keywords: primitive, merges, merged, dissimilar, instantiate

Urgency: Standard

General Description:
When dissimilar register primitives are instantiated in a shift register fashion, Synplify will combine the registers to form an SRL primitive. This is logically incorrect as the FDSE has an INIT value of "1" and the FDRE has an INIT value of "0."


The only work around for now is to use Synplify version 7.7.1, as none of the synthesis directives have an affect on the design.
AR# 21213
Date 04/24/2007
Status Archive
Type General Article