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AR# 15953

5.1i MAP - "ERROR:LIT - KEEPER symbol <net name> can only be attached to an IOB pad net"

Description

Keywords: MAP, KEEPER

Urgency: Standard

General Description:
When I attempt to map a design with KEEPER symbols instantiated on the ports, the following error is reported:

"ERROR:LIT - KEEPER symbol <net name> (output signal=Net_name) can only be attached to an IOB pad net.
ERROR:LIT - The above error message virt_keep_load_rule is repeated XX more times for the following:"

Solution

This error is caused by the fact that no IBUF, OBUF, or OBUFT is connected to the pad net due to trimming, and the DRC check is rejecting the connection between the remaining KEEPER and PAD.

This problem will be fixed in the 6.1i software release.

Meanwhile, you can work around this problem by disabling the logical DRC check in MAP; this is accomplished by setting the following environment variable:

PCs:
set XIL_MAP_SKIP_LOGICAL_DRC =1

Workstations:
setenv XIL_MAP_SKIP_LOGICAL_DRC 1

For more general information about setting ISE environment variables, see (Xilinx Answer 11630).
AR# 15953
Date Created 10/21/2002
Last Updated 09/26/2006
Status Archive
Type General Article