##   Port -- the port of the component to which it is connected.
  ## 

  [Name,name] = mtt_subname(fullname); # Split fullname

  SD = "__";			# Subsystem delimiter
  CD = "\n%%";			# Comment delimiter
  arg_default = "1";		# Default aliased arg

  DEBUG = 0;

  if DEBUG
    disp("=======================================");
    fullname, name, Name, port,causality,known
  endif
  
  eqn="## No equation -- something wrong"; # Default

  if length(known)<2		# Invalid
    known = "  ";
  endif

  if length(Name)>0
  cbg = mtt_cbg(Name);		# Structure for this subsystem

    cbg = mtt_cbg(Name);		# Structure for this subsystem
  endif
  
  if struct_contains (cbg, "ports")
    ## Combine ports with the other subsystems
    for [component_structure, component] = cbg.ports
      eval(sprintf("cbg.subsystems.%s=cbg.ports.%s;",component,component));
    endfor
  endif

  ## Aliasing  
  if length(name)>0
    eval(sprintf("ARG=cbg.subsystems.%s.arg;", name)); # Arguments
    ARG = mtt_alias (Name,ARG,arg_default); # Alias them
    eval(sprintf("cbg.subsystems.%s.arg=ARG;", name)); # and copy
  endif
  

  ## Call to a subsystem (represented by name="")
  if strcmp(name,"")
    if !struct_contains(cbg,"portlist")
      N_ports = 0;
    else