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AR# 11345

3.1i MAP - Use of the MAP "-u" option leads to "ERROR:Pack:679 - Unable to obey design constraints (MACRONAME = multiplier_v2_0_lat_v2/..."

Description

Keywords: MAP, CORE Generator, COREGen, multiplier, mult_gen, error, Pack:, pack, 679, unable to obey design constraints

Urgency: Standard

General Description:
I am using a multiplier core from CORE Generator, and the multiplier type is set as "Non-Constant Parallel Multiplier." When I run MAP with the "-u" option, the following error message is reported:

"ERROR:Pack:679 - Unable to obey design constraints (MACRONAME = multiplier_v2_0_lat_v2/top_level/par_mul/m2/top, RLOC = X2Y9), which require the combination of the following symbols into a single slice component:
LUT symbol "BU104" (Output Signal = N46687)
MULTAND symbol "BU105" (Output Signal = N46689)
MUXCY symbol "BU106" (Output Signal = N45586)
MULTAND symbol "BU109" (Output Signal = N46745)
The output signal of the MULT_AND symbol BU109 must be connected to the input of a MUXCY symbol within the slice. Please correct the design constraints accordingly."

Solution

1

The work-around is to NOT use the "-u" switch when running MAP.

For GUI users:
Be sure to have the "Trim unconnected signals" option selected in the GUI or Properties menu. (The default setting is already selected.)

For command line users:
Do NOT use "-u" when running the MAP command.

This problem was fixed in a multiplier core that was released in (E_IP1) in October, 2001.

2

If the "-u" switch is necessary, set the following environment variable:

XIL_MAP_BETTER_U = 1
AR# 11345
Date Created 04/10/2001
Last Updated 08/19/2002
Status Archive
Type General Article