Glossary
G-2
ni.com
D
DAQ
Data acquisition. (1) Collecting and measuring electrical signals from
sensors, transducers, and test probes or fixtures and inputting them to a
computer for processing. (2) Collecting and measuring the same kinds of
electrical signals with A/D or DIO boards plugged into a computer, and
possibly generating control signals with D/A and/or DIO boards in the
same computer.
DMA
Direct memory access. A method by which data can be transferred to and
from computer memory from and to a device or memory on the bus while
the processor does something else; DMA is the fastest method of
transferring data to/from computer memory.
F
FIFO
First-in first-out memory buffer. The first data stored is the first data sent
to the acceptor; FIFOs are used on Vision devices to temporarily store
incoming data until that data can be retrieved.
L
LVDS
Low Voltage Differential Signaling (EIA-644).
N
NI-IMAQ
Driver software for National Instruments Vision hardware.
P
PCI
Peripheral Component Interconnect. A high-performance expansion bus
architecture originally developed by Intel to replace ISA and EISA. PCI
offers a theoretical maximum transfer rate of 133 Mbytes/s.
pixel
Picture element. The smallest division that makes up the video scan line;
for display on a computer monitor, a pixel’s optimum dimension is square
(aspect ratio of 1:1, or the width equal to the height).
pixel clock
Divides the incoming horizontal video line into pixels.
