HiSLIP (High-Speed LAN Instrument Protocol) is a
TCP/IP
The Internet protocol suite, commonly known as TCP/IP, is a framework for organizing the set of communication protocols used in the Internet and similar computer networks according to functional criteria. The foundational protocols in the suit ...
-based protocol for remote
instrument control
Instrument control consists of connecting a desktop instrument to a computer and taking measurements.
History
In the late 1960s the first bus used for communication was developed by Hewlett-Packard and was called HP-IB (Hewlett-Packard Interfac ...
of
LAN-based test and measurement instruments. It was specified by the IVI Foundation
and is intended to replace the older VXI-11
protocol. Like VXI-11, HiSLIP is normally used via a library that implements the
VISA API.
Version 1.4 of the
LAN eXtensions for Instrumentation
LAN eXtensions for Instrumentation (LXI) is a standard developed by the LXI Consortium, a consortium that maintains the LXI specification and promotes the LXI Standard. The LXI standard defines the communication protocols for instrumentation and ...
(LXI) standard recommends HiSLIP as “LXI HiSLIP Extended Function for LXI based instrumentation”.
Benefits
HiSLIP fixes several problems with the VXI-11 protocol (which synchronously sends GPIB commands via
SunRPC):
* New asynchronous “overlap mode” to help applications fully utilize
Ethernet
Ethernet () is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in ...
performance
* Support for both shared and exclusive instrument locking
* Support for
IPv6
Internet Protocol version 6 (IPv6) is the most recent version of the Internet Protocol (IP), the communications protocol that provides an identification and location system for computers on networks and routes traffic across the Internet. I ...
Features
HiSLIP can operate in two different modes:
* In “overlap mode”, input and output data are buffered between the client and server and a series of independent queries can be sent by a client without having to wait for each to complete before sending the next. The responses are sent back in the order in which the queries were sent. This asynchronous operation helps applications to fully utilize
Ethernet
Ethernet () is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in ...
performance.
* There is also a slower “synchronized mode”, in which a client is required to read the result of each query before it can send another. It is intended for backwards compatibility with the capabilities of
GPIB Glycoprotein Ib (GPIb), also known as CD42,
is a component of the GPIb-V-IX complex on platelets. The GPIb-V-IX complex binds von Willebrand factor, allowing platelet adhesion and platelet plug formation at sites of vascular injury.
It is defici ...
, VXI-11, and USB-TMC instruments.
HiSLIP clients (VISA libraries) have to support both modes. HiSLIP servers (instruments) need to support at least one of them, but can also support both.
A HiSLIP client contacts a server by opening ''two'' TCP connections, both to port 4880, and sends packetized messages on both:
* The “synchronous channel” carries normal bi-directional ASCII command traffic (e.g.,
SCPI), and synchronous GPIB meta-messages (END, triggers, etc.).
* The “asynchronous channel” carries GPIB-like meta-messages that need to be treated at higher priority and independent of the data path (e.g., device clear, service request).
Usage
To migrate from VXI-11 to HiSLIP, a user of a VISA library and instrument that support both merely has to change the VISA resource string used to address the instrument. The shortest possible version of a VXI-11 VISA resource string is "TCPIP::
:: port#:INSTR". To use the HiSLIP communication channel, such a VISA resource string needs to be changed to: "TCPIP::::hislip0::INSTR". If the HiSLIP server is using a port other than the default of 4880, then it must be specified in the resource string as: "TCPIP::IP address, hostname>::hislip0 port#''::INSTR".
References
{{Reflist
External links
* http://www.rohde-schwarz.de/appnote/1MA208 Fast Remote Instrument Control with HiSLIP - Application Note
Input/output
Electronic test equipment
Computer buses