write 2. Synopsys Commands Command Reference
NAME
write Writes a design netlist or schematic
from dc_shell to a file.
SYNTAX
int write [-format output_format] [-hierarchy] [-modified]
[-no_implicit] [-output file] [design_file_list]
string output_format
string file
list design_file_list
ARGUMENTS
-format output_format
Specifies the output format of the
design. If this option is not
specified, the Synopsys internal
database format is used. Supported
output formats are:
Format Description
db Synopsys internal database format
edif Electronic Design Interchange Format
equation Synopsys equation format
lsi LSI Logic Corporation (NDL) netlist format
mentor Mentor NETED do format
pla Berkeley (Espresso) PLA format
st Synopsys State Table format
tdl Tegas Design Language (TDL) netlist format
verilog Cadence Design Systems, Inc.
Hardware Description Language
vhdl IEEE Standard VHDL
xnf Xilinx Netlist Format
-hierarchy Specifies that all the designs in the
hierarchy be written. This option can
be used with any other write option. If
a design hierarchy does not completely
link, unresolved design references are
not written.
-modified Writes only designs whose database
representation have been modified since
the last write command. If this option
is not specified, designs are written
even if they are not changed. -modified
can be combined with any other write
option. Note: If you execute write
2-276 Synopsys Inc. 1988-1994. All rights reserved. V3.1
Command Reference 2. Synopsys Commands write
-modified immediately after reading a
design, Design Compiler will write the
unmodified design.
-no_implicit Specifies that synthetic design
hierarchy implicitly created during
optimization, is not written (saved)
with the design. If this option is not
specified, designs created in the
hierarchy through the use of synthetic
libraries are written (even if the
-hierarchy option is not specified).
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write 2. Synopsys Commands Command Reference
-output file Writes designs into one file. If a
filename is not specified, each design
is written to a separate file named
design.suffix, where design is the name
of each design (a full UNIX path), and
suffix is the default suffix for the
specified format. The default format
suffixes are:
Format Default Suffix
db .db
edif .edif
equation .fnc
lsi .NET
mentor .neted
pla .pla
st .st
tdl .tdl
verilog .v
vhdl .vhd
xnf .xnf
design_file_list
Specifies any number of designs to
write. If edif format is used, and if
the -output file option is used
(specifies that designs are written to
one file), no more than one design can
be specified with design_file_list. The
only way to write more than one design
to a single file in edif format is to
use the -hierarchy option. (This
limitation is imposed to eliminate the
possibility of hierarchical designs
being written in the wrong order, such
as with cells being referenced before
being defined.)
If no designs are specified, the current
design is written. After a design is
written, it still exists in dc_shell.
Use remove_design to remove a design
from dc_shell.
DESCRIPTION
The write command outputs designs from dc_shell to
disk. If a design is modified in dc_shell, write must
be used to save the design.
2-278 Synopsys Inc. 1988-1994. All rights reserved. V3.1
Command Reference 2. Synopsys Commands write
EXAMPLES
Following are examples of saving designs in db format.
The most common use is to write a design to its
assigned file:
dc_shell> write {A, B, C}
Writing to file 'A.db'
Writing to file 'B.db'
Writing to file 'C.db'
If you specify a design that is one of many designs in
a file, all designs are written:
dc_shell> write top
Writing to file 'top.db'
Multiple designs can be written to a single file:
dc_shell> write -output mine.db{ADDER MULT16}
Writing to file 'mine.db'
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write 2. Synopsys Commands Command Reference
With the -hierarchy option, all designs in the
hierarchy of the specified designs are written.
Following are two examples:
dc_shell> write -hierarchy top
Writing to file 'top.db'
Writing to file 'A.db'
Writing to file 'B.db'
dc_shell> write -hierarchy -output ~bill/dc/top.db top
Writing to '~bill/dc/top.db'
The default design filename can be specified instead of
the design name.
Write all the designs that reside in file "top.db":
dc_shell> write top.db
Writing to file '/osi4/bill/dc/top.db'
You can save all designs whose database representation
in dc_shell memory that were modified since the last
write command.
dc_shell> write -modified find( design, "*")
Writing to file 'top.db'
Writing to file 'A.db'
Writing to file 'B.db'
Writing to file 'C.db'
You can read more than one design with the same name
into dc_shell. To avoid ambiguity, specify the file
name when writing the design. You can also have more
than one file with the same name (i.e., top.db and
top.db) in dc_shell. To resolve this conflict, precede
the file name with its full pathname.
In the case of a design name conflict, use the file
name to write the design:
dc_shell> write top
Error: 'top' doesn't specify a unique design
Please use complete specification: full_file_name:design_name
dc_shell> write -hierarchy /osi4/bill/dc/top.db:top
Writing to file '/osi4/bill/dc/top.db'
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Command Reference 2. Synopsys Commands write
In the following example, the file name "top.db" is
ambiguous and must be resolved by using the full
pathname:
dc_shell> write top.db
Error: 'top' doesn't specify a unique design
Please use complete specification: full_file_name:design_name
dc_shell> write /osi4/bill/dc/top.db
Writing to file '/osi4/bill/dc/top.db'
SEE ALSO
list(2), read(2); io_variables(3), suffix_variables:
view_write_file_suffix(3).
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