# CDI service parameters

The CDI service stores its parameters in the following data structures:

- CDI_DTMFDETECTOR_PARMS

- CDI_GLOBAL_PARMS

- CDI_RING_PARMS

- CDI_SIGNALDETECTOR_PARMS

- CDI_TONE_PARMS

Use the following Natural Access functions to obtain or modify parameter information:

Function | Description
--- | ---
ctaGetParmByName | Retrieves a single field for a given parameter name.
ctaSetParmByName | Modifies a single field for a given parameter name.
ctaGetParmInfo | Retrieves a parameter field definition.
ctaGetParms | Returns parameter values for a given parameter structure.
ctaRefreshParms | Resets the values of all context parameters on a context to the global defaults.

For information about parameter management in Natural Access, refer to the Natural Access Developer's Reference Manual.