eldo_user

Eldo Netlist Setup
Directives
Directives
Directives can be used to simulate variations of circuits.
IF, ELSE, ELSEIF, ENDIF Conditional Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
String Operator on If Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Directives Interpreted by the Eldo Parser (Default) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Directives to Postpone Block of Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Directives Interpreted using the C Pre-Processor (-E/-EE Arguments). . . . . . . . . . . . . 126
IF, ELSE, ELSEIF, ENDIF Conditional Statements
IF, ELSE, ELSEIF, and ENDIF conditional statements can be used inside the Eldo netlist and
can be used to instantiate devices depending on parameter size. ELIF and ELSIF keywords are
also accepted as the ELSEIF condition.
• The IF, ELSE, ELSEIF, ENDIF section must not contain any command, otherwise
unexpected results can be obtained. Warnings are issued in this case.
• The parameters used in expressions of if statements are evaluated during the parsing of
the design only, even if these parameters are changed at run time (because of .STEP, for
instance), then the design will not be changed, a message will be issued that the
operation cannot be taken into account. The .ALTER mechanism should be preferred
here.
Example of usage:
.subckt foo 1 param: p1 = 1
if (p1 >= 1.5)
r1 1 0 '2*p1'
else
r1 1 0 '3*p1'
endif
.ends
i1 1 0 3
x1 1 foo p1 = 3
.op
.end
In this example, the value of resistor r1 will be 6 Ω.
Note
Errors are issued if ADMS is used, or if X or Y statements are present inside if-endif blocks.
Tip
See “.IF, .ELSE, .ELSEIF, .ENDIF” in the Eldo Reference Manual.
Eldo® User's Manual, 15.3 121