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Eldo Netlist Setup
Directives Interpreted using the C Pre-Processor (-E/-EE Arguments)
Related Topics
Directives
Directives Interpreted using the C Pre-Processor (-E/-EE Arguments)
Directives Interpreted using the C Pre-Processor
(-E/-EE Arguments)
For an extended use of pre-processor commands to define macros and replace them inside the
netlist (see the example below), the -E or -EE argument needs to be specified. These are not the
Eldo default because the parsing of large circuits may be significantly slower.
The -E argument forces Eldo to provide only the main netlist to the C pre-processor, whereas
-EE ensures that all #include filename statements will be pre-processed before parsing. The
.INCLUDE/.LIB statements, which are SPICE commands, are not understood by the C preprocessor
and so will not be pre-processed.
The #include directive can only be used when the -E/-EE arguments are specified.
Note: The C pre-processor analyses files independently. Therefore #define statements are only
known to the file they are defined in.
The -define argument can also be specified on the command line, and it will have the same
effect as without the -E/-EE arguments. To use #define in Eldo in the same way you define
macros in the C language, the syntax is as follows:
#define macro(args) expression
When the macro is encountered in the netlist, it is replaced by the expression. Arguments of the
macro will be replaced by the literals in the macro call. For example:
#define sat_margin(device) abs(vds(device)-vdss(device))
.extract sat_margin(XM0.M1)
will be replaced by:
.extract abs(vds(XM0.M1)-vdss(XM0.M1))
Note
Because -E/-EE uses the C pre-processor, you must ensure there is a carriage return
proceeding the directive in the file to avoid problems. Uppercase function names are not
accepted. Using comments defined with #com and #endcom are not compatible with -E/-EE.
Related Topics
Directives
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Eldo® User's Manual, 15.3