National Instruments AT-MIO-16X - Manual (Page 302)

Glossary
© National Instruments Corporation G-19 AT-MIO-16X User Manual
ppm parts per million
pretriggering the technique used on a DAQ board 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
propagation the transmission of a signal through a computer system
propagation delay the amount of time required for a signal to pass through a circuit
proportional control a control action with an output that is to be proportional to the deviation
of the controlled variable from a desired setpoint
protocol the exact sequence of bits, characters, and control codes used to transfer
data between computers and peripherals through a communications
channel, such as the GPIB bus
proximity sensor a device that detects the presence of an object without physical contact.
Most proximity sensors provide a digital on/off relay or digital output
signal.
pts points
pulse trains multiple pulses
pulsed output a form of counter signal generation by which a pulse is outputted when
a counter reaches a certain value
Q
quantization error the inherent uncertainty in digitizing an analog value due to the finite
resolution of the conversion process
QuickTime Apple system software tools that make video presentation a standard
part of the Macintosh. Applications can use QuickTime to record and
display audio and video in the same way applications use system tools
to generate and display text and graphics.