nlGetParamStringValue

nlGetParamStringValue( 
o_instance 
s_parameter 
) 
=> t_value / nil

Description

Returns a string representing the parameter value for the instance and parameter name.

The parameter name is the simulator name for the parameter. Values returned are strings irrespective of their original type. If the parameter does not exist or if the value is a blank string, nil is returned.

Value none is no longer recognized as a special keyword. Previously it was treated as being equivalent to nil, but now it is treated as a design variable.

The parameters are evaluated according to the common evaluator. For details, see Chapter 9 of the Compatibility Guide. This means that values of CDF parameters can reference parameters with iPar or pPar that have NLP expressions. The CDF default value can be overridden with an instance property. The property type of that property must be a string.

The following table shows a synopsis of that scheme:

This property...	Is CDF?	And evaluates to...
NLP	yes	nil
NLP	no	As NLP
string	yes	As specified on the CDF
string	no	The literal string

If the parameter is a CDF parameter, this function takes all aspects into account, including the CDF parameter type and the parseAsCEL attribute.

This procedure handles all look-up for pPar, iPar, and atPar, as well as the parameter name map specified for the component.

The AEL pPar and the NLP “+” calls are replaced by the enclosed variable. The passed parameter found is automatically collected. The netlister tracks these parameters for appropriate invalidation purposes.

The AEL iPar and the NLP “~” calls are replaced by the appropriate property values.

The use of the AEL atPar function and the NLP “@” calls is discouraged. Like pPar, these are replaced with the variable specified, and the parameter specified is declared as a passed parameter in the subcircuit.

The AEL dotPar function and the NLP “.” are not supported, and a netlist error is reported if they are used.

The suffixes are substituted according to the suffix mapping specified. Thus, a schematic value “1n” may result in “1e-9”.

Only a limited set of NLP expressions is translated appropriately. The format accepted is limited to:

[<operator> <parameter name>],

[<operator> <parameter name>: % ],

[<operator> <parameter name>: % : <default value>],

with the operator being @, +, or ~.

Many NLP expressions are therefore not supported:

Complex formatting such as :abc%d%e
Formatting on the default clause
Modifiers in front of the operator, such as time and capacitance scaling
Nesting in the default value or value formatting section

For about iPar, pPar, atPar and dotPar functions, see Passing Parameters in a Design.

Arguments

o_instance	The instance object.
s_parameter	The name of the parameter.

Value Returned

t_value	The string form of the parameter value.
`nil`	The parameter was not found, the value was `nil`, the value was an empty string, or the value was a string consisting of only white space.

Examples

nlGetParamStringValue( inst 'tvpairs )

Return to top

Virtuoso ADE SKILL ReferenceProduct Version IC23.1, November 2023