CLASSPREFIX_ATTR_CACHE

To form the CLASSPREFIX_ of the attribute name, use the prefix of the class driver with which you are working. For example, if you are working with the IviDmm class driver, use the prefix IVIDMM_ to create the correct attribute name, IVIDMM_ATTR_CACHE.

Inherent Attribute

Data Type	Access	Applies to	Coercion	High Level Functions
ViBoolean	R/W	N/A	None	None

Description

Specifies whether to cache the value of attributes. When caching is enabled, the specific driver keeps track of the current instrument settings so that it can avoid sending redundant commands to the instrument. State caching can significantly increase execution speed. You specify a value for this attribute for the entire instrument driver. The specific instrument driver can choose to always cache or never cache particular attributes, regardless of how this attribute is set.

You call the ClassPrefix_InvalidateAllAttributes function to invalidate the cache values for all attributes for the session. This is useful when the cached values for attributes no longer match the settings of the instrument. This can happen when you manually configure the instrument through its front panel or when you bypass the instrument driver and control the instrument directly from your program.

The default value is VI_TRUE. You can override this value by specifying a value in MAX or by initializing the IVI session with the ClassPrefix_InitWithOptions function.