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AR# 31108

10.1 Constraint Editor - Group Constraints By Element Type is not working correctly

Description

In Constraint Editor, if I use "Group Constraints" -> "By Element Type", the following syntax gets created:

TIMEGRP "inst5432_reg_grp" = FFS("ffs4_inst5/Source1") FFS("ffs4_inst5/Source3") FFS("ffs4_inst5/Source4") FFS("ffs4_inst4/Source1") FFS("ffs4_inst4/Source2") FFS("ffs4_inst4/Source3") FFS("ffs4_inst4/Source4");

However, the constraint using this TIMEGRP is missing from PCF.

Solution

Constraint Editor is wrongly using the instance name, instead of the net names. There are 2 work-arounds for this issue:

1. You may define the source and destination group separately.

TIMEGRP "src_grp" = FFS("ffs4_inst?/QS?" ); # the name in the brackets is the Source FF output net name

TIMEGRP "dst_grp" = FFS("data_out*"); # the name in the brackets is the Destination FF output net name

2. You may use the INST and TNM constraints for creating the timing group.

INST "ffs4_inst?/Source?" TNM = inst_src_grp; # the name is the source instance name

INST "ffs4_inst?/Destination?" TNM = inst_dst_grp; # the name is the destination instance name

This issue is scheduled to be fixed in the next major release of the design tools.

AR# 31108
Date Created 06/12/2008
Last Updated 12/15/2012
Status Active
Type General Article