next up previous contents
Next: Creating 'other'- elements semi-automatically Up: Hierarchical design Previous: Incorporating external netlists :

Creating 'other'- elements

  The picture of an 'other'-element can be created like a symbol manually. Like a symbol, an 'other' element can be created semi-automatically by reading the model file. This semi-automatical generation of 'other' symbols will be described in the next section.

So, leave SPICECAD and start it again typing
Spice 1 -> cad -o firstother

   

Like in a symbol, contacts need to be placed to connect the subcircuit to the schematics world. Don't forget to give names to the contacts (edit their properties)!

The element is saved using 'sv oth' in the main menu.

After saving, you have to add additional information to the just created file 'firstother.oth' to tell SPICECAD the contact sequence and the netlisting mode (hierarchical/flat).

 

In the following lines, there are two examples of such an information trailer.

hierarchical netlisting mode: .
.
.
stop
;end of graphics primitives section subckt
X
3 IN1 IN2 OUT
notused
1 model

Line entry Meaning
.  
.  
.  
stop End of picture data
subckt keyword . It means that the incorporated netlist contains analog elements
X Prefix (first Letter) , 'X' for subcircuits , 'Y' for digital parts (just under implementation)
3 IN1 IN2 OUT Number and name of contacts. The sequence of names will be the netlist sequence later. Example : X123 IN1_node IN2_node OUT_node f_adder
hierarchical keyword for hierarchical netlisting
1 model number of properties and their names. In the hierarchical netlisting mode, only 'model' has a meaning (it's a keyword). In flat netlisting mode, additional model names may be used.


flat netlisting mode:
.
.
.
stop
subckt
X
3 IN1 IN2 OUT
flat
4 model {par1} {par2} {par3}


next up previous contents
Next: Creating 'other'- elements semi-automatically Up: Hierarchical design Previous: Incorporating external netlists :
Martin Maschmann
1999-10-10