Programming Using Visa Drivers; Visa Description; Vxi-11 Compatibility; Opening The Visa Connection - TDK-Lambda Genesys Series User Manual

7. PROGRAMMING USING VISA DRIVERS

7.1. VISA Description

In the test and measurement industry, Virtual Instrument Software Architecture (VISA) is a popular framework
that includes hardware drivers, configuration utilities and connection managers. A variety of communication
busses are supported. VISA drivers are available from several instrument vendors.
Any programming language that supports Windows COM or DLL libraries can call the VISA functions. VISA
drivers may be downloaded for Windows, Linux and MAC OS. Some licensing issues may apply.
Remote programming uses a computer's LAN connection to send text commands to the power supply,
and to read text responses back. The format of the text messages is called SCPI (see section 11)

7.2. VXI-11 Compatibility

VXI-11 is a protocol that allows communications between a computer port and an instrument.
VISA is built upon the VXI-11 specification. The Genesys™ power supply is compatible with the
VXI-11 protocols:
o VXI–11 Device_link Open link to instrument
o VXI–11 Device_write Write text to the instrument
o VXI–11 Device_read Read text from an instrument
o VXI–11 Destroy_link Close link to instrument

7.3. Opening the VISA Connection

Test and automation programs may easily be written if they use the VISA libraries. The supported VISA
functions include Open, Read, Write and Close A VISA resource descriptor is used to describe a particular
supply. For a Genesys™ LAN
power supply, the descriptors are found on the supply's Home web page. The VISA resource may use the
supply's IP address or hostname Example VISA resource descriptors for the Genesys™ power supply with
LAN are:
Format:
TCPIP[board]::host address[::LAN device name][::INSTR]
[board]
[::LAN device name] is by default "inst0"
[::INSTR]
Examples:
TCPIP::10.225.26.60::inst0::INSTR
TCPIP::169.254.57.10::INSTR
TCPIP1::GEN60-25-470::INSTR
See the sample programs, section 14, for examples

7.4. Communicating Using VISA

The VISA Write function will send SCPI commands to the power supply, the VISA read will read the response
returned from a SCPI query. For programming examples and support, refer to the VISA vendor's web site.
is the LAN card number, zero is optional
is optional
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