nero

NERO(1)                  Alliance - nero User's Manual                 NERO(1)



NAME
       nero - Negotiating Router

SYNOPSIS
       nero [ -h ]  [ -v ]  [ -V ]  [ -c ]  [ -2 ]  [ -3 ]  [ -4 ]  [ -5 ]  [
       -6 ]  [ -L ]  [ -G ]
        [ --help ]  [ --verbose ]  [ --very-verbose ]  [ --core-dump ]  [
       --local ]  [ --global ]
        [ -p placement ]  netlist layout

DESCRIPTION
       nero is a simple router suited for small academic designs. Currently it
       can process designs of size up to 4K gates.

   GLOBAL ROUTING
       A design is considered as big if it contains nets which half perimeter
       is greater than 800 lambdas.  Global routing is used on big designs.

       In nero, "global routing" means that the longuests nets are completly
       routed in a first step with only routing layers numbers 3 & 4. Then the
       smaller nets are routed with all avalaibles layers. This implies that
       when global routing is used, the number of routing layers is forced to
       at least 4.  In each step, the nets are routed from the shortest to the
       longuest with the same routing algorithm.

INVOCATION
       nero mandatory arguments :

       • netlist : the name of the design, whithout any extention. Please note
         that unless a -p placement option is given, the file holding the
         placement is expected to have the same name as the netlist file
         (short of the extention).

       • layout : the name of the resulting routed layout. Be careful of not
         giving the same name as the netlist, in this case the initial
         placement will be silently overwritten.

       nero optionnals arguments :

       • -h, --help : print help.

       • -v, --verbose : be verbose.

       • -V, --very-verbose : be unbearably verbose.

       • -c, --core-dump : do not prevent the generation of core dumps in case
         of a crash.  Mostly used during the development stage.

       • -2, -3, -4, -5, -6 : set the numbers of layers used for routing. The
         default for small designs is 2 and 4 for big ones. When global
         routing took place, the router will uses at least 4 routing layers.

       • -L, --local : turn off the global routing stage, whatever the size of
         the design.  Be warned that this will enormously slow down the
         routing process.

       • -G, --global : turn on the global routing regardless of the size of
         the design.

       • -p placement, --place placement : specify a name for the placement
         file different from the netlist name.

EXAMPLE
       Route the netlist amd2901_core.vst, using the placement file
       amd2901_core_p.ap and store the result in amd2901_core_r.

       $ export MBK_IN_LO=vst
       $ export MBK_IN_PH=ap
       $ export MBK_OUT_PH=ap
       $ nero -V --place amd2901_core_p amd2901_core amd2901_core_r



SEE ALSO
       MBK_IN_LO(1), MBK_OUT_LO(1), MBK_IN_PH(1), MBK_OUT_PH(1), ocp(1),
       ocr(1), druc(1), cougar(1)



ASIM/LIP6                       13 October 2002                        NERO(1)