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NI RFmx Instruments General Functions

Alex Starche edited this page Mar 1, 2022 · 2 revisions

General Functions

RFmxInstr_Initialize

int32 __stdcall RFmxInstr_Initialize (char resourceName[], char optionString[], niRFmxInstrHandle *handleOut, int32 *isNewSession);

Purpose

Creates an RFmx session to the signal analyze you specify through the resourceName parameter, and returns a handleOut that identifies this device in all subsequent RFmx functions.

Enabling the SFP (Soft Front Panel) debug has a performance impact. For best performance, NI recommends disabling SFP debug.

On a 64-bit Windows, SFP debug can be enabled/disabled from either the RFmx Soft Front Panel, the RFSA Soft Front Panel, or the RFmx Debug Configuration Utility.

On a 32-bit Windows, SFP debug can be enabled/disabled from the RFSA Soft Front Panel or the RFmx Debug Configuration Utility.

Parameters

Input
Name Type Description
resourceName char[] Specifies the resource name of the device to initialize. Use comma separated resource names for initializing MIMO session.

The following table shows examples of how to specify the resource name.
Example # Device Type Syntax
1 myRFmxDevice RFmx device, device name is "myRFmxDevice"
2 myLogicalName IVI logical name or virtual instrument, name is "myLogicalName"
3 [myRFmxDevice0, myRFmxDevice1.,] RFmx device, device name is "myRFmxDevice0"


For NI-DAQmx devices, the syntax is the device name specified in MAX, as shown in Example 1. Typical default names for NI-DAQmx devices in MAX are Dev1 or PXI1Slot2. You can rename an NI-DAQmx device by right-clicking the name in MAX, selecting Rename from the pull-down menu, and entering a new name. You can also pass the name of an IVI logical name configured with the IVI Configuration utility. For additional information about IVI, refer to the IVI section of the Measurement & Automation Explorer Help.
optionString char[]

Sets the initial value of certain attributes for the session.

The following attributes are used in this parameter:

- RFmxSetup

- Simulate

- AnalysisOnly



For more information about attributes used in this parameter, refer to the NI RF Vector Signal Analyzers Help.

The format of this string is "AttributeName=Value", where AttributeName is the name of the attribute and Value is the value to which the attribute is set. For example, you can simulate an PXIe-5663E using either of the following strings:

"Simulate=1, RFmxSetup=Model:5663E"

"Simulate=1, RFmxSetup=Model:5601; Digitizer:5622; LO:5652; LOBoardType:PXIe"

To set multiple attributes, separate their assignments with a comma.

To use FPGA extensions, specify the custom LabVIEW FPGA bitfile to use with the bitfile specifier within the RFmxSetup string. For example, "RFmxSetup=bitfile:yourbitfile.lvbitx" specifies that RFmx uses yourbitfile.lvbitx as the LabVIEW FPGA bitfile for the session.

To use AnalysisOnly mode, specify the string as "AnalysisOnly=1" or "AnalysisOnly=1;MaxNumWfms:n", where "n" represents the maximum number of waveforms that can be used for the MIMO measurement. In this mode, user is responsible for waveform acquisition and RFmx driver will perform analysis on user specified IQ waveform(s) or Spectrum(s). Use personality specific Analyze functions to perform measurements.

Note To simulate a device using the PXIe-5622 (25 MHz) digitizer, set the Digitizer field to 5622_25MHz_DDC and the Simulate field to 1. You can set the Digitizer field to 5622_25MHz_DDC only when using the PXIe-5665.
isNewSession int32* Returns RFMXInstr_VAL_TRUE if the function created a new session, or RFMXInstr_VAL_FALSE if the function returned a reference to an existing session.
Output
Name Type Description
handleOut niRFmxInstrHandle* Identifies your instrument session.

Return Value

Name Type Description
status int32 Returns the status code of this operation. The status code either indicates success or describes an error or warning condition. Examine the status code from each call to an RFmx function to determine if an error has occurred.

To obtain a text description of the status code and additional information about the error condition, call the RFmxInstr_GetError) function.

The general meaning of the status code is as follows:
Value Meaning
0 Success
Positive Values Warnings
Negative Values Errors

RFmxInstr_Close

int32 __stdcall RFmxInstr_Close (niRFmxInstrHandle instrumentHandle, int32 forceDestroy);

Purpose

Closes the RFmx session.

Parameters

Input
Name Type Description
instrumentHandle niRFmxInstrHandle Identifies the instrument session. This parameter is obtained from the RFmxInstr_Initialize function or the RFmxInstr_InitializeFromNIRFSASessionArray function.
forceDestroy int32 Indicates whether to forcefully destroy the RFmx session.
RFMXInstr_VAL_FALSE (0) Destroys the RFmx session only if you call the RFmxInstr_Close function a number of times equal to the number of times you obtained a reference to the RFmx session.
RFMXInstr_VAL_TRUE (1) Forcefully destroys the RFmx session. You do not have to call the RFmxInstr_Close function multiple times. Destroying the RFmx session invalidates all references to the session.

Return Value

Name Type Description
status int32 Returns the status code of this operation. The status code either indicates success or describes an error or warning condition. Examine the status code from each call to an RFmx function to determine if an error has occurred.

To obtain a text description of the status code and additional information about the error condition, call the RFmxInstr_GetError) function.

The general meaning of the status code is as follows:
Value Meaning
0 Success
Positive Values Warnings
Negative Values Errors

RFmxInstr_GetError

int32 __stdcall RFmxInstr_GetError (niRFmxInstrHandle instrumentHandle, int32* errorCode, int32 errorDescriptionBufferSize, char errorDescription[]);

Purpose

Retrieves and then clears the error information for the session or the current execution thread. You must provide a char array to serve as a buffer for the value. Pass the number of bytes in the buffer as the errorDescriptionBufferSize parameter.

If the error description, including the terminating NULL byte, is larger than the size you indicate in the errorDescriptionBufferSize parameter, the function copies buffer size - 1 bytes into the buffer, places an ASCII NULL byte at the end of the buffer, and returns the buffer size you must pass to get the entire value. For Example, if the value is "123456" and the buffer size is 4, the function places "123" into the buffer and returns 7.

If you want to call this function just to get the required buffer size, you must pass 0 for errorDescriptionBufferSize and NULL for the errorDescription buffer.

Note  Use the RFmxInstr_GetErrorString) function if the RFmxInstr_GetError function does not return an error message.

Parameters

Input
Name Type Description
instrumentHandle niRFmxInstrHandle Specifies the RFmx session. If a valid session handle is passed, the last error stored in that session is retrieved. You can pass NULL to retrieve the last error stored in the current execution thread.
errorCode int32* Returns the error code for the session or execution thread. If you pass 0 for the errorDescriptionBufferSize parameter, you can pass NULL for the errorCode parameter.
errorDescriptionBufferSize int32 Passes the number of bytes in the char array you specify in the errorDescription parameter.

If the error description, including the terminating NULL byte, contains more bytes than you indicate in this parameter, the function copies errorDescriptionBufferSize – 1 bytes into the buffer, places an ASCII NULL byte at the end of the buffer, and returns the size of the buffer that you must pass to get the entire value. For example, if the value is "123456" and the buffer size is 4, the function places "123" into the buffer and returns 7.
errorDescription char[] Returns the error description for the session or execution thread. If there is no description, this function returns an empty string.

The buffer must contain at least as many elements as the value you specify with the errorDescriptionBufferSize parameter.

Return Value

Name Type Description
statusOrRequiredSize int32 Returns the status code of this operation. The status code either indicates success or describes an error or warning condition. Examine the status code from each call to an RFmx function to determine if an error has occurred.

When the statusOrRequiredSize return value returns the buffer size, the status code is not returned.

To obtain a text description of the status code and additional information about the error condition, call the RFmxInstr_GetError) function.

The general meaning of the status code is as follows:
Value Meaning
0 Success
Positive Values Warnings
Negative Values Errors

RFmxInstr_GetErrorString

int32 __stdcall RFmxInstr_GetErrorString (niRFmxInstrHandle instrumentHandle, int32 errorCode, int32 errorDescriptionBufferSize, char errorDescription[]);

Purpose

Converts a status code returned by an RFmxInstr function into a user-readable string. You must provide a char array to serve as a buffer for the value. Pass the number of bytes in the buffer as the errorDescriptionBufferSize parameter.

If the error description, including the terminating NULL byte, is larger than the size you indicate in the errorDescriptionBufferSize parameter, the function copies buffer size - 1 bytes into the buffer, places an ASCII NULL byte at the end of the buffer, and returns the buffer size you must pass to get the entire value. For Example, if the value is "123456" and the buffer size is 4, the function places "123" into the buffer and returns 7.

If you want to call this function just to get the required buffer size, you must pass 0 for errorDescriptionBufferSize and NULL for the errorDescription buffer.

Parameters

Input
Name Type Description
instrumentHandle niRFmxInstrHandle Identifies the instrument session. This parameter is obtained from the RFmxInstr_Initialize function or the RFmxInstr_InitializeFromNIRFSASessionArray function.
errorCode int32 Passes the statusOrRequiredSize parameter that is returned from any RFmxInstr function.
errorDescriptionBufferSize int32

Passes the number of bytes in the char array that you specify in the errorDescription array. If the error description, including the terminating NULL byte, contains more bytes than you indicate in this parameter, the function copies (errorDescriptionBufferSize - 1) bytes into the buffer, places an ASCII NULL byte at the end of the buffer, and returns the size of the buffer that you must pass to get the entire value. For example, if the value is "123456" and the buffer size is 4, the function places "123" into the buffer and returns 7.

If a valid session handle is passed, this parameter displays the last error stored in that session. You can pass NULL to this parameter to retrieve the last error stored in the current execution thread.

errorDescription char[] Returns the user-readable message string that corresponds to the error code you specify.

If you pass 0 for the errorDescriptionBufferSize, you can pass NULL for the errorDescription buffer parameter to get the size of error description message.

Return Value

Name Type Description

Table of Contents

Internal Development

Creating and Setting Up a gRPC Server

Server Security Support

Creating a gRPC Client

gRPC Client Examples

Session Utilities API Reference

Driver Documentation

gRPC API Differences From C API

Sharing Driver Sessions Between Clients

C API Docs
NI-DAQmx
NI-DCPOWER
NI-DIGITAL PATTERN DRIVER
NI-DMM
NI-FGEN
NI-FPGA
NI-RFmx Bluetooth
NI-RFmx NR
NI-RFmx WCDMA
NI-RFmx GSM
NI-RFmx CDMA2k
NI-RFmx Instr
NI-RFmx LTE
NI-RFmx SpecAn
NI-RFmx TD-SCDMA
NI-RFmx WLAN
NI-RFSA
NI-RFSG
NI-SCOPE
NI-SWITCH
NI-TCLK
NI-XNET
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