GetAttrRangeTable

IVI Library

Ivi_GetAttrRangeTable

Usage

ViInt32 = Ivi_GetAttrRangeTable(ViSession vi, ViChar repeatedCapability[ ], ViAttr attributeID, IviRangeTablePtr* rangeTable);

Purpose

This function returns a pointer to the range table for an attribute. If you call Ivi_SetAttrRangeTableCallback to install a range table callback function for the attribute, Ivi_GetAttrRangeTable invokes your range table callback with the vi, AttributeID, and RepeatedCapability parameters. Otherwise, Ivi_GetAttrRangeTable returns the address of the range table you specify for the attribute when you call Ivi_AddAttributeViInt32, Ivi_AddAttributeViReal64, or Ivi_SetStoredRangeTablePtr.

To bypass the range table callback and always return the range table you store for the attribute, call Ivi_GetStoredRangeTablePtr.

If you install your own check callback function in addition to either a range table or a range table callback, call this function from the check callback to obtain a pointer to the range table.

Parameters

Name Type Description
vi ViSession

The ViSession handle that you obtain from Ivi_SpecificDriverNew. The handle identifies a particular IVI session.

repeatedCapability ViChar[ ]

If the attribute is repeated capability-based, specify a particular repeated capability. If the attribute you specify is not repeated capability-based, pass VI_NULL or an empty string.

attributeID ViAttr

Pass the ID of an attribute for this parameter.

The include file for a specific instrument driver defines constant names for all of the user-accessible attributes that apply to the driver. This includes attributes that the IVI engine defines, attributes that the instrument class defines, and attributes that are specific to the particular instrument. Each defined constant name begins with PREFIX_ATTR_, where PREFIX is the specific instrument prefix.

For each IVI engine attribute, the specific driver include file uses the same constant name that appears in ivi.h, except that the specific instrument prefix replaces the IVI prefix. For example, ivi.h defines IVI_ATTR_CACHE, and the Fluke 45 include file, fl45.h, defines the following constant name:

#define FL45_ATTR_CACHEĀ  IVI_ATTR_CACHE

For each instrument class attribute, the specific driver include file uses the same constant name that appears in the instrument class include file, except that the specific instrument prefix replaces the class prefix. For example, the DMM class include file, ividmm.h, defines IVIDMM_ATTR_RANGE, and fl45.h defines the following constant name:

#define FL45_ATTR_RANGEĀ  IVIDMM_ATTR_RANGE

For each specific instrument attribute, the specific driver include file defines a constant name and assigns a value that is an offset from IVI_SPECIFIC_PUBLIC_ATTR_BASE. For example, fl45.h defines the following constant name:

#define FL45_ATTR_HOLD_THRESHOLD \ (IVI_SPECIFIC_PUBLIC_ATTR_BASE + 3L)

For each attribute that is private to an instrument driver, the instrument driver source file defines a constant name and assigns a value that is an offset from IVI_SPECIFIC_PRIVATE_ATTR_BASE. For example, hp34401a.c defines the following constant name:

#define HP34401A_ATTR_TRIGGER_TYPE \ (IVI_SPECIFIC_PRIVATE_ATTR_BASE + 1L)

rangeTable IviRangeTablePtr*

This parameter returns the address of the range table for the attribute.

Return Value

Contains the status code that the function call returns. IVI engine functions can return error and warning values from several sets of status codes. Some status codes are unique to the IVI engine. Other status codes are the same codes that VISA Library functions return. Still others are error or warning values that functions in specific instrument drivers return. Each set of status codes has its own numeric range.

Regardless of the source of the status code, 0 always indicates success, a positive value indicates a warning, and a negative value indicates an error.

Related Topic

IVI Status Codes