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ngspice man-page

SPICE(1)							      SPICE(1)

       spice - circuit simulator

       spice [ -n ] [ -t term ] [ -r rawfile] [ -b ] [ -i ] [ input file ... ]

       This manual page describes the commands available for  interactive  use
       of SPICE3. For details of circuit descriptions and the process of simu-
       lating a circuit, see the SPICE3 User’s Manual.	The commands available
       are a superset of those available for nutmeg - only the additional com-
       mands available in SPICE3 are described here.  You should  be  familiar
       with the manual page for nutmeg(1) before reading this manual page.

       Arguments are:

       -n (or --no-spiceinit)
	      Don’t try to source the file ".spiceinit" upon startup. Normally
	      SPICE3 tries to find the file in the current directory,  and  if
	      it is not found then in the user’s home directory.

       -q (or --completion)
	      Enable command completion.

       -t term (or --term=term)
	      The program is being run on a terminal with mfb name term.

       -b (or --batch)
	      Run  in  batch  mode. SPICE3 will read the standard input or the
	      specified input file and do the simulation.  Note	 that  if  the
	      standard	input  is not a terminal, SPICE3 will default to batch
	      mode, unless the -i flag is given.

       -s (or --server)
	      Run in server mode. This is like batch mode, except that a  tem-
	      porary  rawfile is used and then written to the standard output,
	      preceded by a line with a single "@", after  the	simulation  is
	      done. This mode is used by the spice daemon.

       -i (or --interactive)
	      Run in interactive mode. This is useful if the standard input is
	      not a terminal but interactive mode is desired. Command  comple-
	      tion  is	not available unless the standard input is a terminal,

       -r rawfile (or --rawfile=file)
	      Use rawfile as the default file into which the  results  of  the
	      simulation are saved.

       -c circuitfile (or --circuitfile=circuitfile)
	      Use circuitfile as the default input deck.

       -h (or --help)
	      Display  a  verbose  help on the arguments available to the pro-

       -v (or --version)
	      Display a version number and copyright information of  the  pro-

       Further	arguments  are	taken to be SPICE3 input decks, which are read
       and saved. (If batch mode is requested then they are run	 immediately.)

       SPICE3  will  accept  any  SPICE2  input decks, and output ascii plots,
       fourier analyses, and node printouts as specified in .plot, .four,  and
       .print cards.  If a out parameter is given on a .width card, the effect
       is the same as set width = ....	Since SPICE3 ascii plots  do  not  use
       multiple ranges, however, if vectors together on a .plot card have dif-
       ferent ranges they will not provide as much information as  they	 would
       in  SPICE2. The output of SPICE3 is also much less verbose than SPICE2,
       in that the only data printed is that requested by the above cards.

       Vector names are the same as in nutmeg, with this addition: a name such
       as  @name[param], where name is either the name of a device instance or
       model, denotes the value of the param parameter of the device or model.
       See  the SPICE3 User’s Manual for details of what parameters are avail-
       able. The value is a vector of length 1.	 This function is also	avail-
       able  with the show command, and is available with variables for conve-
       nience for command scripts.

       SPICE3 commands are as follows (these are only those commands not  also
       available  in  nutmeg  -	 consult  the nutmeg manual page for more com-

       setcirc [circuit name]
	      Change the current circuit. The current circuit is the one  that
	      is  used	for  the  simulation commands below. When a circuit is
	      loaded with the source command (see below) it becomes  the  cur-
	      rent circuit.

       op [.op card args]
	      Do an operating point analysis.

       tran [.tran card args]
	      Do a transient analysis.

       ac [.ac card args]
	      Do an ac analysis.

       dc [.dc card args]
	      Do a dc transfer curve analysis.

       listing [logical] [physical] [deck] [expand]
	      Print  a listing of the current circuit. If the logical argument
	      is given, the listing is with all continuation  lines  collapsed
	      into  one	 line, and if the physical argument is given the lines
	      are printed out as they were found in the file. The  default  is
	      logical.	A  deck	 listing  is  just  like the physical listing,
	      except without the line numbers it recreates the input file ver-
	      batim  (except  that  it	does  not preserve case).  If the word
	      expand is present, the circuit will be printed with all  subcir-
	      cuits expanded.

       edit [file]
	      Print the current SPICE3 deck into a file, call up the editor on
	      that file and allow the user to modify it, and then read it back
	      in,  replacing  the  origonal deck. If a filename is given, then
	      edit that file and load it, making the circuit the current  one.

       resume Resume a simulation after a stop.

       show   Show a device parameter.

       alter  Alter a device parameter.

       state  Print  the state of the circuit.	(This command is largely unim-

       save [all] [output ...]	or .save [all] [output ...]
	      Save a set of outputs, discarding the rest. If a node  has  been
	      mentioned	 in a save command, it will appear in the working plot
	      after a run has completed, or in the rawfile if spice is run  in
	      batch  mode.  If a node is traced or plotted (see below) it will
	      also be saved. For backward compatibility, if there are no  save
	      commands given, all outputs are saved.

       stop [ after n] [ when something cond something ] ...
	      Set a breakpoint. The argument after n means stop after n itera-
	      tion number n, and the argument when  something  cond  something
	      means  stop  when	 the  first something is in the given relation
	      with the second something, the possible relations being eq or  =
	      (equal  to), ne or <> (not equal to), gt or > (greater than), lt
	      or < (less than), ge or >= (greater than or equal to), and le or
	      <=  (less than or equal to).  IO redirection is disabled for the
	      stop command, since the relational operations conflict  with  it
	      (it  doesn’t  produce  any output anyway).  The somethings above
	      may be node names in the running circuit, or  real  values.   If
	      more than one condition is given, e.g.  stop after 4 when v(1) >
	      4 when v(2) < 2, the conjunction of the conditions is implied.

       trace [ node ...]
	      Trace nodes. Every iteration the value of the node is printed to
	      the standard output.

       iplot [ node ...]
	      Incrementally plot the values of the nodes while SPICE3 runs.

       step [number]
	      Iterate number times, or once, and then stop.

       status Display all of the traces and breakpoints currently in effect.

       delete [debug number ...]
	      Delete  the  specified breakpoints and traces. The debug numbers
	      are those shown by the status command. (Unless you do  status  >
	      file, in which case the debug numbers aren’t printed.)

       reset  Throw  out  any  intermediate  data in the circuit (e.g, after a
	      breakpoint  or  after  one  or  more  analyses  have  been  done
	      already), and re-parse the deck. The circuit can then be re-run.
	      (Note: this command used to be end in SPICE 3a5 and earlier ver-
	      sions  -- end is now used for control structures.)  The run com-
	      mand will take care  of  this  automatically,  so	 this  command
	      should not be necessary...

       run [rawfile]
	      Run the simulation as specified in the input file. If there were
	      any of the control cards .ac, .op, .tran, or .dc, they are  exe-
	      cuted. The output is put in rawfile if it was given, in addition
	      to being available interactively.

       source file
	      Read the SPICE3 input file file. Nutmeg and SPICE3 commands  may
	      be  included in the file, and must be enclosed between the lines
	      .control and .endc.  These  commands  are	 executed  immediately
	      after  the  circuit  is loaded, so a control line of ac ... will
	      work the same as the corresponding .ac card.  The first line  in
	      any  input  file	is  considered a title line and not parsed but
	      kept as the name of the circuit. The exception to this  rule  is
	      the  file	 .spiceinit.  Thus, a SPICE3 command script must begin
	      with a blank line and then with a .control line.	Also, any line
	      beginning	 with  the characters *# is considered a control line.
	      This makes it possible to imbed commands in SPICE3  input	 files
	      that  will  be  ignored  by earlier versions of SPICE.  Note: in
	      spice3a7 and before, the	.control  and  .endc  lines  were  not
	      needed, and any line beginning with the name of a front-end com-
	      mand would be executed.

       linearize vec ...
	      Create a new plot with all of the vectors in the	current	 plot,
	      or only those mentioned if arguments are given.  The new vectors
	      will be interpolated onto a linear time scale, which  is	deter-
	      mined by the values of tstep, tstart, and tstop in the currently
	      active transient	analysis.   The	 currently  loaded  deck  must
	      include a transient analysis (a tran command may be run interac-
	      tively before the last reset, alternately), and the current plot
	      must  be	from  this transient analysis.	This command is needed
	      because SPICE3 doesn’t output the results from a transient anal-
	      ysis in the same manner that SPICE2 did.

       There  are  several set variables that SPICE3 uses but nutmeg does not.
       They are:

		       The editor to use for the edit command.

		       The name of the model card (normally .model).

		       Do not check to make sure that there  are  no  circuits
		       suspended  and  no plots unsaved.  Normally SPICE3 will
		       warn the user when he tries to  quit  if	 this  is  the

		       Assume that BJT’s have 4 nodes.

		       Don’t  attempt  to  parse  decks	 when they are read in
		       (useful for debugging). Of course, they cannot  be  run
		       if they are not parsed.

		       Don’t expand subcircuits.

		       Renumber input lines when a deck has .include’s.

		       The card to end subcircuits (normally .ends).

		       The prefix to invoke subcircuits (normally x).

		       The card to begin subcircuits (normally .subckt).

       There  are  a number of rusage parameters available, in addition to the
       ones available in nutmeg:

       If there are subcircuits in the input file, SPICE3 expands instances of
       them.   A  subcircuit  is  delimited by the cards .subckt and .ends, or
       whatever the value of the variables substart  and  subend  is,  respec-
       tively.	An  instance of a subcircuit is created by specifying a device
       with type ’x’ - the device line is written

	      xname node1 node2 ... subcktname

       where the nodes are the node names that replace the  formal  parameters
       on  the	.subckt	 line.	All  nodes  that are not formal parameters are
       prepended with the name given to the instance and a  ’:’,  as  are  the
       names  of  the  devices	in the subcircuit. If there are several nested
       subcircuits, node and device names look like  subckt1:subckt2:...:name.
       If  the	variable  subinvoke is set, then it is used as the prefix that
       specifies instances of subcircuits, instead of ’x’.

       The standard suffix for rawspice files in VMS is ".raw".

       You may have to redefine the value EDITOR if you wish to use  the  edit
       command, since the default for VMS is "vi".

       nutmeg(1),  sconvert(1),	 spice(1),  mfb(3), writedata(3) SPICE3 User’s

       SPICE3:	Tom Quarles (
       nutmeg / User interface: Wayne Christopher (

       SPICE3 will recognise all the notations used in SPICE2 .plot cards, and
       will translate vp(1) into ph(v(1)), and so forth. However, if there are
       spaces in these names it won’t work. Hence v(1, 2) and (-.5, .5) aren’t

       BJT’s  can  have	 either 3 or 4 nodes, which makes it difficult for the
       subcircuit expansion routines to decide what to rename. If  the	fourth
       parameter  has  been  declared as a model name, then it is assumed that
       there are 3 nodes, otherwise it is considered a node. To	 disable  this
       kludge, you can set the variable "nobjthack", which will force BJT’s to
       have 4 nodes (for the purposes of subcircuit expansion, at least).

       The @name[param] notation might not work with trace, iplot, etc.	  yet.

       The  first  line	 of  a	command	 file (except for the .spiceinit file)
       should be a comment.  Otherwise	SPICE  may  create  an	empty  circuit

       SPICE3 files specified on the command line are read in before the .spi-
       ceinit file is read. Thus if you define aliases there that you call  in
       a  SPICE3  source  file	mentioned  on  the command line, they won’t be

4th Berkeley Distribution	 20 March 1986			      SPICE(1)
geda/ngspice_mp.txt · Last modified: 2012/02/20 15:14 (external edit)