Frame API for C
This topic lists the NI-CAN functions and describes the format, purpose and parameters.
Unless otherwise stated, each NI-CAN function suspends execution of the calling thread until it completes. The functions in this topic are listed alphabetically.
Section Headings
The following are section headings found in the Frame API for C functions.
Purpose
Each function description includes a brief statement of the purpose of the function.
Format
The format section describes the format of each function for the C programming language.
Input and Output
The input and output parameters for each function are listed.
Description
The description section gives details about the purpose and effect of each function.
Network Interface Object
The Network Interface Object section gives details about using the function with the Network Interface Object.
CAN Object
The CAN Object section gives details about using the function with the CAN Object.
Data Types
The following data types are used with functions of the NI-CAN Frame API for C.
| Data Type | Purpose |
|---|---|
| NCTYPE_INT8 | 8-bit signed integer |
| NCTYPE_INT16 | 16-bit signed integer |
| NCTYPE_INT32 | 32-bit signed integer |
| NCTYPE_UINT8 | 8-bit unsigned integer |
| NCTYPE_UINT16 | 16-bit unsigned integer |
| NCTYPE_UINT32 | 32-bit unsigned integer |
| NCTYPE_BOOL | Boolean value. Constants NC_True (1) and NC_False (0) are used for comparisons. |
| NCTYPE_STRING | ASCII string represented as an array of characters terminated by null character (`\0' ). |
| NCTYPE_type_P | Pointer to a variable of type. |
| NCTYPE_ANY_P | Pointer to a variable of any type, used in cases where actual data type can vary depending on the object in use. |
| NCTYPE_OBJH | 32-bit unsigned integer used to reference an open object in the Frame API. |
| NCTYPE_ATTRID | Attribute identifier. Uses constants with prefix NC_ATTR_. |
| NCTYPE_OPCODE | Operation code for ncAction function. Uses constants with prefix NC_OP_. |
| NCTYPE_STATE | Object states, encoded as a 32-bit mask, one bit for each state. Refer to ncWaitForState for more information. |
| NCTYPE_STATUS | Status returned from NI-CAN functions. Refer to ncStatusToString for more information. |
| NCTYPE_CAN_ARBID | CAN arbitration ID. The 30h bit is accessed using bitmask NC_FL_CAN_ARBID_XTD (2000000 hex). If this bit is clear, the CAN arbitration ID is standard (11-bit). If this bit is set, the CAN arbitration ID is extended (29-bit). Special constant NC_CAN_ARBID_NONE (CFFFFFFF hex) indicates no CAN arbitration ID, and is used to set the comparator attribute of the CAN Network Interface. Refer to ncConfig for more information. |
List of Functions
The following table contains an alphabetical list of the NI-CAN Frame API for C functions.
| Function | Purpose |
|---|---|
| ncAction | Perform an action on an object. |
| ncCloseObject | Close an object. |
| ncConfig | Configure an object before using it. |
| ncConnectTerminals | Connect terminals in the CAN hardware. |
| ncCreateNotification | Create a notification call back for an object. |
| ncDisconnectTerminals | Disconnect terminals in the CAN hardware. |
| ncGetAttribute | Get the value of an object attribute. |
| ncGetHardwareInfo | Get NI-CAN hardware information. |
| ncOpen | Open an object. |
| ncRead | Read the data value of an object. |
| ncReadMult | Read multiple data values from the queue of an object. |
| ncSetAttribute | Set the value of an object attribute. |
| ncStatusToString | Convert status code into a descriptive string. |
| ncWaitForState | Wait for one or more states to occur in an object. |
| ncWrite | Write the data value of an object. |
| ncWriteMult | Write multiple frames to a CAN Network Interface Object. |