Glossary

Plug and Play devices

Devices that do not require DIP switches or jumpers to configure resources

 

on the devices. Also called switchless devices port.

 

1. A communications connection on a computer or a remote controller;

 

2. A digital port, consisting of four or eight lines of digital input and/or

 

output.

posttriggering

The technique used on a DAQ device to acquire a programmed number of

 

samples after trigger conditions are met.

power source

An instrument that provides one or more sources of AC or DC power. Also

 

known as power supply.

ppm

Parts per million.

pretriggering

The technique used on a DAQ device to keep a continuous buffer filled with

 

data, so that when the trigger conditions are met, the sample includes the

 

data leading up to the trigger condition.

pulse

A signal whose amplitude deviates from zero for a short period of time.

pulse width

The time from the rising to the falling slope of a pulse (at 50% amplitude).

PXI

A rugged, open system for modular instrumentation based on CompactPCI,

 

with special mechanical, electrical, and software features. The PXIbus

 

standard was originally developed by National Instruments in 1997, and is

 

now managed by the PXIbus Systems Alliance.

PXI Express

PCI Express eXtensions for Instrumentation—The PXI implementation of

 

PCI Express, a scalable full-simplex serial bus standard that operates at

 

2.5 Gbps and offers both asynchronous and isochronous data transfers.

PXI_STAR

A special set of trigger lines in the PXI backplane for high-accuracy device

 

synchronization with minimal latencies on each PXI slot. Only devices in

 

the PXI Star controller Slot 2 can set signal on this line. For additional

 

information concerning PXI star signal specifications and capabilities, read

 

the PXI Specification located at www.pxisa.org/specs.