National Instruments Image Acqusition Software NI-IMAQdx Benutzerhandbuch
Chapter 3
Advanced Programming with NI-IMAQdx
© National Instruments Corporation
3-3
The following value types are compatible for any given attribute type.
The bolded compatible value type indicates the native value type. For
example, use a 32-bit unsigned integer value type when dealing with a
32-bit unsigned integer attribute type. Optionally, use a signed 64-bit
integer, double precision floating point, or string when dealing with a 32-bit
unsigned integer attribute type.
example, use a 32-bit unsigned integer value type when dealing with a
32-bit unsigned integer attribute type. Optionally, use a signed 64-bit
integer, double precision floating point, or string when dealing with a 32-bit
unsigned integer attribute type.
Attribute Access
Each attribute has a read access and a write access. Use the Is Attribute
Readable function to query read access for a given attribute. Use the Is
Attribute Writable function to query write access for a given attribute.
Some attributes are only settable before configuring the acquisition, while
other attributes can be changed at any time.
Readable function to query read access for a given attribute. Use the Is
Attribute Writable function to query write access for a given attribute.
Some attributes are only settable before configuring the acquisition, while
other attributes can be changed at any time.
Attribute Range
Most attributes have a specific range of valid values. Use the Get Attribute
Minimum, Get Attribute Maximum, and Get Attribute Increment
functions to query the range of numeric attribute types. Use the Enumerate
Attribute Values function to query the range of enumerated types. String,
bool, and command attributes do not have a range.
Minimum, Get Attribute Maximum, and Get Attribute Increment
functions to query the range of numeric attribute types. Use the Enumerate
Attribute Values function to query the range of enumerated types. String,
bool, and command attributes do not have a range.
Table 3-3. Attribute Types and Compatible Value Types
Attribute Type
Compatible Value Types
U32
U32, I64, F64, String
I64
U32, I64, F64, String
F64
U32, I64, F64, String
String
String
Enum
U32, I64, F64, String, EnumItem
Bool
U32, I64, F64, String, Bool
Command
U32, I64, F64, String, Bool