Provided by: alliance_5.0-20110203-4_i386
nero - Negotiating Router
nero [ -h ] [ -v ] [ -V ] [ -c ] [ -2 ] [ -3 ] [ -4 ] [ -5 ] [
-6 ] [ -L ] [ -G ]
[ --help ] [ --verbose ] [ --very-verbose ] [ --core-dump ] [
--local ] [ --global ]
[ -p placement ] netlist layout
nero is a simple router suited for small academic designs. Currently it
can process designs of size up to 4K gates.
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.
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
· -G, --global : turn on the global routing regardless of the size of
· -p placement, --place placement : specify a name for the placement
file different from the netlist name.
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
MBK_IN_LO(1), MBK_OUT_LO(1), MBK_IN_PH(1), MBK_OUT_PH(1), ocp(1),
ocr(1), druc(1), cougar(1)