National Instruments DIO 6533 - Manual (Page 118)

Glossary
DIO 6533 User Manual G-10 © National Instruments Corporation
TTL transistor-transistor logic
U
unstrobed digital I/O a type of digital input or output in which software reads or writes the
digital line or port states directly, without using any handshaking or
hardware-controlled timing functions. Also called immediate,
nonhandshaking, or unlatched digital I/O.
update the output equivalent of a scan. One or more analog or digital output
samples. Typically, the number of output samples in an update is equal
to the number of channels in the output group. For example, one pulse
from the update clock produces one update which sends one new sample
to every analog output channel in the group.
V
V volts
V
cc
the voltage of the power supply from the computer, approximately 5 V
VDC volts direct current
V
IH
volts, input high
V
IL
volts, input low
V
in
volts in
V
OH
volts, output high
V
OL
volts, output low
V
ref
reference voltage
W
wire data path between nodes
wired-OR a type of output driver that provides sink current but little or no source
current, and is typically used with a pull-up resistor to provide source
current. If you connect two or more wired-OR outputs together, any one