Glossary
SCXI-1102/B/C User Manual
G-4
©
National Instruments Corporation
DOUT
digital output signal
drivers/driver software
software that controls a specific hardware device such as a DAQ device
E
EISA
Extended Industry Standard Architecture
ESP
Engineering Software Package
EXTCONV
external control signal to trigger A/D conversions
EXTINT
external interrupt signal
F
F
farads
FIFO
first-in first-out memory buffer—the first data stored is the first data
sent to the acceptor. FIFOs are often used on DAQ devices to
temporarily store incoming or outgoing data until that data can be
retrieved or output. For example, an analog input FIFO stores the results
of A/D conversions until the data can be retrieved into system memory,
a process that requires the servicing of interrupts and often the
programming of the DMA controller. This process can take several
milliseconds in some cases. During this time, data accumulates in the
FIFO for future retrieval. With a larger FIFO, longer latencies can be
tolerated. In the case of analog output, a FIFO permits faster update
rates, because the waveform data can be stored on the FIFO ahead of
time. This again reduces the effect of latencies associated with getting
the data from system memory to the DAQ device.
ft
feet
G
G
gain
GATE
gate input signal
