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AR# 4321

Synopsys, M1.4 ngdbuild : WARNING:basxn:70 - 870 obsolete timing specification(s) was/were found:


Keywords: sxnf, timespec, XACT, ncf, WARNING:basxn:70, 870,

Urgency : Standard

General Description:
When running ngdbuild, you get the following WARNING:

reading XNF file
WARNING:basxn:70 - 870 obsolete timing specification(s)
was/were found:
XACTstep 5.x specifications will be ignored. Please
re-create these
specifications using the XACTstep M1.x syntax, if you have
not already done so.

On the sxnf file you have TIMESPEC similar to the following:
SYM, TSR109, TIMESPEC, TS864=P2S:760.00:RESET, TS865=P2S:760.00:RESET,
TS866=P2S:760.00:RESET, TS867=P2S:760.00:RESET, TS868=P2S:760.00:RESET,


The above warning is caused by FPGA Compiler writing out the old
style timespecs by default into the .sxnf netlist. The style used
for writing these constraints are no longer supported in M1. To
prevent the old-style timespecs from being written the Synopsys

xnfout_constraints_per_endpoint = 0

must be present in either the .synopsys_dc.setup file or executed
before writing out the .sxnf netlist. This and other required
configuration settings are included in the
$XILINX/synopsys/examples/template.synopsys_dc.setup_fc example
setup file included in the M1 release.

This warning will have no effect on the functionality of the
circuit however the timespecs issed withing the .sxnf netlist will
be ignored by the M1 timing driving placement and routing. The
method to transport timing specifications from the Synthesis tool
to M1 is by the use of the utility DC2NCF. For more information on
using DC2NCF please consult the Synopsys (XSI) Interface/Tutorial

It is suggested to re-write out the .sxnf file, using the
file, or equivalent files depending on the device family.

Another option is to ignore the messages with the kowledge that the
timespecs within the netlist will not be used by the M1 software.
In the Synopsys -> M1 flow, all timespec should and will be
entered through NCF or UCF files.
AR# 4321
Date Created 07/24/1998
Last Updated 03/19/2000
Status Archive
Type General Article