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BOOG(1)			   CAO-VLSI Reference Manual		       BOOG(1)

       BooG - Binding and Optimizing On	Gates.

       boog  [-hmxold] input_file output_file  [lax_file]

       boog  is	 a mapper of a behavioural description onto a predefined stan-
       dard cell library as SXLIB.  It is the second step of the logic synthe-
       sis: it builds a	gate network using a standard cell library.

	 Input file description
       The  logic level	behavioural description	(.vbe file) uses the same VHDL
       subset as the logic simulator asimut,  the  FSM	synthesizer  syf,  the
       functional  abstractor  yagle  and the formal prover proof (for further
       information about the subset of VHDL, see the "vbe" manual).
       Some constraints	due to hardware	mapping	exist.	These  attributes  are
       only  supported	by  technology mapping onto a standard cell library as
       For the register	signal description, only one condition statement  must
       appear. STABLE must be strictely	used as	a negativ motion and joined to
       clock setup value. Setup	can be on high or low value, but it  would  be
       worthy to choose	it accordingly with hardware register cell.
       # Example
	       label: BLOCK (NOT ck 'STABLE and	ck='1')
		   reg <= GUARDED expr;
	       END BLOCK;

       You can also put	a write	enable condition to your register:
	       label: BLOCK (NOT ck 'STABLE and	ck='1' and wen='1')
		   reg <= GUARDED expr;
	       END BLOCK;

       A  special  feature  has	been introduced	in the VHDL subset in order to
       allow the don't care description	for external outputs and internal reg-
       isters  :  A  bit  signal can take the 'd' value.  This value is	inter-
       preted as a '0' by the logic simulator asimut.  Don't Cares  are	 auto-
       matically generated by syf in the resulting '.vbe' file.

	 Output	file description
       A  pure	standard cell netlist is produced by boog. This	file is	desti-
       nated for /fBloon/fP  alliance  utility	to  improve  RC	 delays.   Any
       equipotential  keeps  its  name from connector to connector. In trouble
       case, buffers are inserted to respect this VHDL constraint.

	 lax Parameter file description
       The lax file is common with other logic synthesis tools and is used for
       driving the synthesis process.  See lax(5) manual for more detail.

       lax  uses  a  lot  of  parameters  to guide every step of the synthesis
       process.	 Some parameters are globally used (for	example,  optimization
       level  whereas  others  are specifically	used (load capacitance for the
       netlist optimization only).  Here is the	 default  lax  file  (see  the
       user's  manual  for  further information	about the syntax of the	'.lax'

	  Optimization mode = 2	(50% area - 50%	delay)
	  Input	impedance = 0
	  Output capacitance = 0
	  Delayed input	= none
	  Auxiliary signal saved = none

	 Mapping with a	standard cell library
       Every cell appearing in the directory defined by	the environment	 vari-
       able  MBK_TARGET_LIB  may be used by boog since they are	described as a
       '.vbe' file. There are some restrictions	about the  type	 of  the  cell
       used. Every cell	has to have only one output.  The cell must be charac-
       terized.	The timing and area informations required by boog  are	speci-
       fied in the "generic" clause of the ".vbe" file.

       -h	 Help mode. Displays possible uses of boog.

       -m optim_mode
		 Optimization  mode.  Can  be defined in lax file, it's	only a
		 shortcut to define it on command line.	This mode  number  has
		 an array defined between 0 and	4. It indicates	the way	of op-
		 timization the	user wants. If 0 is chosen, the	 circuit  area
		 will  be  improved. On	the other hand,	4 will improve circuit
		 delays. 2 is a	medium value for optimization.

       -x xsch_mode
		 Generate a '.xsc' file. It is a color map  for	 each  signals
		 contained  in	output_file network. This file is used by xsch
		 to view the netlist. By choosing level	0 or 1 for  xsch_mode,
		 you  can  color respectively the critical path	or all signals
		 with delay graduation.

       -o output_file
		 Just another way to show  explicitely	the  VST  output  file

       -l lax_file
		 Just  another	way to show explicitely	the LAX	parameter file

       -d debug_file
		 Generates a VBEdebug file. It comes from internal result  al-
		 gorithm. Users	aren't concerned.

       The following environment variables have	to be set before using boog :

       MBK_CATA_LIB  gives  the	 auxiliary  paths  of the directories of input
	      files (behavioural description).

       MBK_TARGET_LIB gives the	path (single) of the directory of the selected
	      standard cell library.

       MBK_OUT_LO gives	the output format of the structural description.

       You can call boog as follows :
	    boog alu alu

       boog(1),	  boom(1),   loon(1),  lax(5),	vbe(5),	 proof(1),  asimut(1),
       vhdl(5),	ocp(1),	nero(1), sxlib(5).

ASIM/LIP6			  Jun 29 2000			       BOOG(1)


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