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AR# 13320

5.1i Virtex-II MAP - "ERROR:MapLib:487 - COUT pin of MUXCY symbol "xxx" (output signal=<none>) is not connected to a signal..."

Description

Keywords: error, MapLib, 487, COUT, MUXCY, multiplier, LUT, CORE Generator, COREGen

Urgency: Standard

General Description:
It is not unusual for CORE Generator modules to contain MUXCY symbols with no output signal attached. Normally, the MUXCY is trimmed with no problems; however, if a user finds it necessary to run MAP with trimming disabled because the design is incomplete, MAP can fail with the error:

"ERROR:MapLib:487 - COUT pin of MUXCY symbol "xlxi_1/BU287" (output signal=<none>) is not connected to a signal. This will cause problem with downstream tools. If '-u' behavior is intended, you should attach a signal to the output of MUXCY so that it can be programmed properly."

Solution

The following environment variable work-around is available in 4.1i MAP; it instructs MAP to handle this special-case trimming issue appropriately:

For PCs:
SET XIL_MAP_BETTER_U=1

For Workstations:
setenv XIL_MAP_BETTER_U 1

This option becomes the default trimming setting for 6.1i.
AR# 13320
Date Created 12/04/2001
Last Updated 09/26/2006
Status Archive
Type General Article