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[/] [w11/] [tags/] [w11a_V0.74/] [rtl/] [vlib/] [cdclib/] [cdc_signal_s1.xdc] - Rev 38
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# -*- tcl -*-
# $Id: cdc_signal_s1.xdc 759 2016-04-09 10:13:57Z mueller $
#
# Copyright 2016- by Walter F.J. Mueller <W.F.J.Mueller@gsi.de>
# License disclaimer see LICENSE_gpl_v2.txt in $RETROBASE directory
#
# cdc constraints for cdc_signal_s1
#
# Revision History:
# Date Rev Version Comment
# 2016-04-08 759 1.0 Initial version
#
set clko [get_clocks -of_objects [get_cells R_DO_S0_reg]]
set clko_per80 [expr {0.8 * [get_property -min PERIOD $clko]}]
#
# CLKI->CLK0
# ensure timing delay in DI smaller than a receiver clock cycle
# Note: -datapath_only requires -from to be specified; -from must be a
# clock (or primary port); a -from clock can't be reliably determined
# because 'single signal' synchronizer might be driven by logic or
# even by a constant. So simply use [get_clock], thus all clocks.
set_max_delay \
-from [get_clocks] \
-to [get_cells {R_DO_S0_reg}] \
-datapath_only $clko_per80