Addressing a Session
From Agilent VISA.NET
Addressing a Session
As shown in the previous section, the rsrcName parameter in the viOpen function is used to identify a specific resource. This parameter consists of the VISA interface ID and the resource address. The interface ID is determined when you run the Agilent Connection Expert utility. The interface ID is usually the VISA interface type followed by a number.
The following table illustrates the format of the rsrcName for different VISA interface types. INSTR is an optional parameter that indicates that you are communicating with a resource that is of type INSTR, meaning instrument. The keywords are:
- ASRL - used for asynchronous serial devices.
- GPIB - used for GPIB devices and interfaces.
- GPIB-VXI - used for GPIB-VXI controllers.
- PXI - used for modular instruments.
- TCPIP - used for LAN and HiSLIP instruments.
- VXI - used for VXI instruments.
- USB - used for USB instruments.
|
Interface |
Typical Syntax |
|
ASRL |
ASRL[board][::INSTR] |
|
GPIB |
GPIB[board]::primary address[::secondary address][::INSTR] |
|
GPIB |
GPIB[board]::INTFC |
|
GPIB-VXI |
GPIB-VXI[board]::VXI logical address[::INSTR] |
|
GPIB-VXI |
GPIB-VXI[board]::MEMACC |
|
GPIB-VXI |
GPIB-VXI[board][::VXI logical address]::BACKPLANE |
|
PXI |
PXI[bus]::device[::function][::INSTR] |
|
PXI |
PXI[interface]::bus-device[.function][::INSTR] |
|
PXI |
PXI[interface]::CHASSISchassis::SLOTslot[::FUNCfunction][::INSTR] |
|
PXI |
PXI[interface]::MEMACC |
|
TCPIP |
TCPIP[board]::host address[::LAN device name]::INSTR |
|
TCPIP |
TCPIP[board]::host address[::HiSLIP device name[,HiSLIP port]][::INSTR] |
|
TCPIP |
TCPIP[board]::host address::port::SOCKET |
|
USB |
USB[board]::manufacturer ID::model code::serial number[::USB interface number][::INSTR] |
|
VXI |
VXI[board]::VXI logical address[::INSTR] |
|
VXI |
VXI[board]::MEMACC |
|
VXI |
VXI[board][::VXI logical address]::BACKPLANE |
The following table describes the parameters shown in the table above.
|
Parameter |
Description |
|
board |
This optional parameter is used if you have more than one interface of the same type. The default value for board is 0. |
|
host address |
A hostname or a dot-delimited IPv4 IP address for TCPIP. The IP address (in dot-delimited decimal notation) or the name of the host computer/gateway. For the HiSLIP and Raw Sockets protocols only, the host address can be an IPv6 address in square brackets, [fe80::218:e77f] for example. |
|
HiSLIP device name |
The assigned name for the HiSLIP device (the name must begin with hislip). Only address strings specifically requesting a HiSLIP connection via the HiSLIP device name will get a HiSLIP connection.The default HiSLIP device name is hislip0. |
|
HiSLIP port |
The port number to use for a HiSLIP connection. The default is 4880. |
|
LAN device name |
The assigned name for a LAN device. Device name depends on LAN Host Device (see documentation that came with your LAN Host device, such as E5810A). The default is inst0. |
|
manufacturer ID |
Manufacturer’s ID for a USB Test & Measurement-class device |
|
model code |
Model code of a USB device. |
|
port |
The port number to use for a TCP/IP socket connection. |
|
primary address |
The primary address of the GPIB device. |
|
secondary address |
This optional parameter is the secondary address of the GPIB device. If no secondary address is specified, none is assumed. |
|
serial number |
Serial number of a USB device. |
|
USB interface number |
Interface number of a USB device. |
|
VXI logical address |
Logical address of a VXI instrument within a mainframe. |
Some examples of valid VISA addresses follow.
|
Address String |
Description |
|
VXI0::1::INSTR |
A VXI device at logical address 1 in VXI interface VXI0. |
|
GPIB-VXI::9::INSTR |
A VXI device at logical address 9 in a GPIB-VXI controlled VXI system. |
|
GPIB::1::0::INSTR |
A GPIB device at primary address 1 and secondary address 0 in GPIB interface 0. |
|
ASRL1::INSTR |
A serial device located on port 1. |
|
VXI::MEMACC |
Board-level register access to the VXI interface. |
|
GPIB-VXI1::MEMACC |
Board-level register access to GPIB-VXI interface number 1. |
|
GPIB2::INTFC |
Interface or raw resource for GPIB interface 2. |
|
VXI::1::BACKPLANE |
Mainframe resource for chassis 1 on the default VXI system, which is interface 0. |
|
GPIB-VXI2:: BACKPLANE |
Mainframe resource for default chassis on GPIB-VXI interface 2. |
|
PXI0::3-18::INSTR |
PXI device 18 on bus 3. |
|
PXI0::3-18.2::INSTR |
Function 2 on PXI device 18 on bus 3. |
|
PXI0::21::INSTR |
PXI device 21 on bus 0. |
|
PXI0::CHASSIS1::SLOT4::INSTR |
PXI device in slot 4 of chassis 1. |
|
PXI0::MEMACC |
Access to system controller memory available to PXI devices. |
|
TCPIP0::1.2.3.4::999::SOCKET |
Raw TCPIP access to port 999 at the specified address. |
| TCPIP0::[fe80::1]::999::SOCKET | Raw TCPIP using IPv6 address |
|
TCPIP::devicename@company.com::INSTR |
TCPIP device using VXI-11 located at the specified address. This uses the default LAN Device Name of inst0. |
|
TCPIP0::[fe80::1]::hislip0::INSTR |
A TCP/IP device using HiSLIP located at IPv6 IP address fe80::1. |
|
USB::0x1234::0x5678::A22-5::INSTR |
A USB device with manufacturer ID 0x1234, model code 0x5678, and serial number A22-5. This uses the device's first available USBTMC interface. This is usually number 0. |
Example: Opening a Session
This sample shows one way to open a VISA session with the GPIB device at primary address 23.
ViSession defaultRM, vi;
.
.
viOpenDefaultRM(&defaultRM);
viOpen(defaultRM, "GPIB0::23::INSTR", VI_NULL, VI_NULL,&vi);
.
.
viClose(vi);
viClose(defaultRM);