Keysight-Defined VISA Attributes

This topic summarizes the attributes specific to Keysight's VISA implementation. They are defined in the visa.h file distributed with Keysight VISA.

	The `#define KTVISA_ATTRIBUTES` statement must appear before the `#include <visa.h>` statement if you are using any Keysight-defined attributes.
	Attributes are local or global. A local attribute only affects the session specified. A global attribute affects the specified device from any session. Attributes can also be read only (RO) and read/write (RW).

SCPI/TULIP Information

Attribute	Attribute Value	Access Privileges	Data Type	Range	Used by	Description
VI_KTATTR_LOCKWAIT	0x0FFF002BL	RW	Local	ViBoolean	VI_TRUE / VI_FALSE	all VISA sessions	Indicates whether a lock-abiding VISA function that has been exclusively locked by another session will: wait the timeout value to acquire the lock and then return VI_ERROR_TMO if it can't (VI_TRUE case) or return a VI_ERROR_RSRC_LOCKED error immediately (VI_FALSE case).

Attribute

Attribute Value

Access Privileges

Data Type

Range

Used by

Description

VI_KTATTR_LOCKWAIT

0x0FFF002BL

Local

ViBoolean

VI_TRUE / VI_FALSE

all VISA sessions

Indicates whether a lock-abiding VISA function that has been exclusively locked by another session will:

wait the timeout value to acquire the lock and then return VI_ERROR_TMO if it can't (VI_TRUE case) or
return a VI_ERROR_RSRC_LOCKED error immediately (VI_FALSE case).

TCPIP Attributes

Attribute	Attribute Value	Access Privileges	Data Type	Range	Used by	Description
VI_KTATTR_INTERFACE_PROTOCOL	0x0FFF001FL	RO	Local	ViUInt32	VI_KTPROT_VXI11 VI_KTPROT_SICLLAN VI_KTPROT_HISLIP VI_KTPROT_UNKNOWN (on non-LAN sessions)	INSTR, INTFC	The interface protocol being used on this session.
VI_KTATTR_REMOTE_INTF_TYPE	0x0FFF001CL	RO	Local	ViUInt16	VI_INTF_GPIB VI_INTF_ASRL VI_INTF_VXI VI_KTINTF_USRDEF VI_KTINTF_LANINST VI_KTINTF_RSIB VI_KTINTF_SOCKET VI_KTINTF_HISLIP VI_INTF_USB	INSTR, INTFC	The type of remote interface for this session. Notes: Defined only on TCPIP sessions. Remote VI_INTF_VXI sessions support only message-based VXI devices. VXI memory access functions are not supported over LAN (viPeek, viPoke, viMove, etc.). VI_KTINTF_USRDEF, VI_KTINTF_LANINST, and VI_KTINTF_RSIB are returned form VXI-11.3 and SICL-LAN.3 based instruments. VI_KTINTF_SOCKET is returned from a socket connection. VI_KTINTF_HISLIP is returned from a socket connection.

Attribute

Attribute Value

Access Privileges

Data Type

Range

Used by

Description

VI_KTATTR_INTERFACE_PROTOCOL

0x0FFF001FL

Local

ViUInt32

VI_KTPROT_VXI11

VI_KTPROT_SICLLAN

VI_KTPROT_HISLIP

VI_KTPROT_UNKNOWN (on non-LAN sessions)

INSTR, INTFC

The interface protocol being used on this session.

VI_KTATTR_REMOTE_INTF_TYPE

0x0FFF001CL

Local

ViUInt16

VI_INTF_GPIB

VI_INTF_ASRL

VI_INTF_VXI

VI_KTINTF_USRDEF

VI_KTINTF_LANINST

VI_KTINTF_RSIB

VI_KTINTF_SOCKET

VI_KTINTF_HISLIP

VI_INTF_USB

INSTR, INTFC

The type of remote interface for this session.

Notes:

Defined only on TCPIP sessions.
Remote VI_INTF_VXI sessions support only message-based VXI devices. VXI memory access functions are not supported over LAN (viPeek, viPoke, viMove, etc.).
VI_KTINTF_USRDEF, VI_KTINTF_LANINST, and VI_KTINTF_RSIB are returned form VXI-11.3 and SICL-LAN.3 based instruments.
VI_KTINTF_SOCKET is returned from a socket connection.
VI_KTINTF_HISLIP is returned from a socket connection.

Export Attributes

Attribute	Attribute Value	Access Privileges	Data Type	Range	Used by	Description
VI_KTATTR_EXPORT_ENABLED	0x0FFF0020L	RW	Global	ViBoolean	VI_TRUE / VI_FALSE	All VISA sessions	Determines whether the resource should be exported and thus be visible to another vendor’s VISA implementation. The default value for this attribute depends on the VISA interface.
VI_KTATTR_FIND_ONLY_EXPORTED_RSRCS	0x0FFF0021L	RW	Local	ViBoolean	VI_TRUE / VI_FALSE	DefaultRM sessions only	When this attribute is VI_TRUE, only those resources whose VI_KTATTR_EXPORT_ENABLED attribute is VI_TRUE will be returned from viFindRsrc() and viParseRsrc(). The default value is VI_FALSE, which means that all resources will be returned regardless of the value of their VI_KTATTR_EXPORT_ENABLED attribute.

Attribute

Attribute Value

Access Privileges

Data Type

Range

Used by

Description

VI_KTATTR_EXPORT_ENABLED

0x0FFF0020L

Global

ViBoolean

VI_TRUE /
VI_FALSE

All VISA sessions

Determines whether the resource should be exported and thus be visible to another vendor’s VISA implementation.

The default value for this attribute depends on the VISA interface.

VI_KTATTR_FIND_ONLY_EXPORTED_RSRCS

0x0FFF0021L

Local

ViBoolean

VI_TRUE /
VI_FALSE

DefaultRM sessions only

When this attribute is VI_TRUE, only those resources whose VI_KTATTR_EXPORT_ENABLED attribute is VI_TRUE will be returned from viFindRsrc() and viParseRsrc().

The default value is VI_FALSE, which means that all resources will be returned regardless of the value of their VI_KTATTR_EXPORT_ENABLED attribute.

GPIB Attributes

Attribute	Attribute Value	Access Privileges	Data Type	Range	Used by	Description
VI_KTATTR_GPIB_T1_DELAY	0x0FFF0028L	RW	Global	ViiNT32	VI_KT_GPIB_T1DELAY_MIN to VI_KT_GPIB_T1DELAY_MAX (value is in nanoseconds)	GPIB INTFC resources	The value is the time of t1 delay in nanoseconds. Note: Most GPIB interfaces support only a small number of t1 delays, so the actual t1 delay value used by the interface could be different than that specified. The actual delay value used may be retrieved by calling viGetAttribute().
VI_KTATTR_INTERFACE_PROTOCOL	0x0FFF001FL	RO	Local	ViUInt32	VI_KTPROT_VXI11 VI_KTPROT_SICLLAN VI_KTPROT_HISLIP VI_KTPROT_UNKNOWN (on non-LAN sessions)	INSTR, INTFC	The interface protocol being used on this remote session. Undefined if this interface is not remote.

Attribute

Attribute Value

Access Privileges

Data Type

Range

Used by

Description

VI_KTATTR_GPIB_T1_DELAY

0x0FFF0028L

Global

ViiNT32

VI_KT_GPIB_T1DELAY_MIN to VI_KT_GPIB_T1DELAY_MAX (value is in nanoseconds)

GPIB INTFC resources

The value is the time of t1 delay in nanoseconds.

Note: Most GPIB interfaces support only a small number of t1 delays, so the actual t1 delay value used by the interface could be different than that specified. The actual delay value used may be retrieved by calling viGetAttribute().

VI_KTATTR_INTERFACE_PROTOCOL

0x0FFF001FL

Local

ViUInt32

VI_KTPROT_VXI11

VI_KTPROT_SICLLAN

VI_KTPROT_HISLIP

VI_KTPROT_UNKNOWN (on non-LAN sessions)

INSTR, INTFC

The interface protocol being used on this remote session. Undefined if this interface is not remote.

PXI Attributes

This section contains information specific to the Windows product.

Attribute	Attribute Value		Access Privileges		Data Type	Range	Used by	Description
VI_KTATTR_PXI_OOOWRITE_ALLOW_EN	0x0FFF0053L		RW	Local	ViBoolean	VI_TRUE, VI_FALSE	VISA PXI sessions	This is a Keysight-specific attribute that is now superseded by the standard VISA attribute VI_ATTR_PXI_ALLOW_WRITE_COMBINE.

Miscellaneous Attributes

Attribute	Attribute Value	Access Privileges		Data Type	Range	Used by	Description
VI_KTATTR_ALLOW_LOCAL_SPACE_FIFO	0x0FFF0032L	RW	Local	ViBoolean	VI_TRUE / VI_FALSE (default)	All VISA sessions	This attribute was added in VISA 3.0. The VISA 3.0 spec required that in viMove, the srcIncrement/destIncrement from/to local memory is ignored. This means FIFO moves from/to local memory are disallowed. Keysight's VISA implementation allowed FIFO moves from/to local memory in VISA implementations prior to VISA 3.0 so this represents a change in behavior in VISA 3.0 Setting this attribute to VI_TRUE will revert to the pre-VISA 3.0 behavior and allow FIFO moves from/to local memory. Note: The default behavior can be changed by modifying the registry DWORD value: DefaultAllowLocalSpaceFifo to 1 in: HKLM\SOFTWARE\Keysight\IO Libraries\CurrentVersion\VisaInfo
VI_KTATTR_INTERFACE_PROTOCOL	0x0FFF001FL	RO	Local	ViUInt32	VI_KTPROT_VXI11 VI_KTPROT_SICLLAN VI_KTPROT_HISLIP VI_KTPROT_UNKNOWN (on non-LAN sessions)	INSTR, INTFC	The interface protocol being used on this remote session. This applies to TCPIP, Remote GPIB, Remote ASRL, and Remote USB interfaces. Undefined if this interface is not remote.
VI_KTATTR_INTFC_SERIALNUMBER	0x0FFF0045L	RO	Global	ViString	N/A	INTFC sessions only	This attribute was added in Suite 15.1. It returns the serial number of an interface. If the interface does not have a serial number it returns an empty string. Interfaces that don’t support this attribute will return the VI_ERROR_NSUP_ATTR status code.
VI_KTATTR_RETURN_ALL	0x0FFF0062L	RW	Global	ViBoolean	VI_TRUE/VI_FALSE	VISA DefaultRM session	Specifies whether VISA's viFindRsrc function returns all of the instruments discovered by the Discovery Service.
VI_KTATTR_VISA_FRAMEWORK_DIR	0x0FFF003BL	RO	Global	ViString	N/A	VISA defaultRM session	Returns the directory where VISA is installed.
VI_KTATTR_IOLIBRARIES_DIR	0x0FFF003CL	RO	Global	ViString	N/A	VISA defaultRM session	Returns the directories where the IO Libraries are installed.
VI_KTATTR_IOLIBRARIES_REG_PATH	0x0FFF003DL	RO	Global	ViString	N/A	VISA defaultRM session	(Windows only) Returns the registry path for the Keysight IO Libraries Suite.