National Instruments DAQPad-6507, Руководство пользователя

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DAQPad-6507/6508 User Manual G-6 © National Instruments Corporation
Glossary
DCS distributed control system—a large-scale process control system
characterized by a distributed network of processors and I/O subsystems
that encompass control, user interfacing, data collection, and system
management. DCSs are commonly used in large industrial facilities, such
as a petroleum refinery or paper mill.
default setting a default parameter value recorded in the driver. In many cases, the default
input of a control is a certain value (often 0) that means use the current
default setting. For example, the default input for a parameter may be do
not change current setting, and the default setting may be no AMUX-64T
boards. If you do change the value of such a parameter, the new value
becomes the new setting. You can set default settings for some parameters
in the configuration utility or manually using switches located on the
device.
device a plug-in DAQ board, card, or pad that can contain multiple channels and
conversion devices. Plug-in boards, PCMCIA cards, and devices such as
the DAQPad-1200, which connects to your computer parallel port, are all
examples of DAQ devices. SCXI modules are distinct from devices, with
the exception of the SCXI-1200, which is a hybrid.
DGND digital ground signal
digital port See port.
digital trigger a TTL level signal having two discrete levels—a high and a low level
DIN Deutsche Industrie Norme
DIO digital input/output
DIP dual inline package
DIRQ0 PPI D interrupt request bit for Port A
DIRQ1 PPI D interrupt request bit for Port B
DMA direct memory access
DNL differential nonlinearity
DOS disk operating system
downstream the direction of data flow from the host computer or away from the host