Справочник Пользователя для National Instruments MXI Series

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Glossary
G-2
ni.com
D
device
A plug-in instrument board or pad that can contain multiple channels and 
conversion devices. Plug-in boards and PCMCIA cards, which connect to 
your computer parallel port, are examples of devices.
digital trigger
A TTL level signal having two discrete levels—a high and a low level.
DMA
Direct Memory Access—a method by which data can be transferred 
to/from computer memory from/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
FPGA
Field Programmable Gate Array—a logic device that has its functionality 
defined after it is manufactured.
I
IEEE
Institute of Electrical and Electronics Engineers.
P
PCI
Peripheral Component Interconnect—a high-performance expansion bus 
architecture originally developed by Intel to replace ISA and EISA. It is 
achieving widespread acceptance as a standard for PCs and workstations; 
it offers a theoretical maximum transfer rate of 132 Mbytes/s.
PCI Express
A scalable full-simplex serial bus standard that operates at 2.5 Gbps and 
offers both asynchronous and isochronous data transfers.
PCI-PCI bridge
A device that transparently expands the PCI bus on a computer 
motherboard to another bus segment in the same machine. The bridge 
expands the number of PCI expansion slots, but remains transparent to the 
end user.
PXI
PCI eXtensions for Instrumentation. PXI is an open specification 
that builds off the CompactPCI specification by adding 
instrumentation-specific features.