National Instruments 370551A-01 用户手册

daisy-chain

A method of propagating signals along a bus, in which the devices are 
prioritized on the basis of their position on the bus.

Data Transfer Bus

DTB; one of four buses on the VMEbus backplane. The DTB is used by 
a bus master to transfer binary data between itself and a slave device.

DIP

Dual Inline Package.

DMA

Direct Memory Access; a method by which data is transferred between 
devices and internal memory without intervention of the central processing 
unit.

DRAM

Dynamic RAM.

driver window

A region of PCI address space that is decoded by the PCI-MXI-2 for use by 
the NI-VXI software.

DTACK*

Data Acknowledge signal.

DTB See Data Transfer Bus.

dynamically configured 
device

A device that has its logical address assigned by the Resource Manager. 
A VXI device initially responds at Logical Address 255 when its MODID 
line is asserted. A MXIbus device responds at Logical Address 255 during 
a priority select cycle. The Resource Manager subsequently assigns it a new 
logical address, which the device responds to until powered down.

dynamic configuration

A method of automatically assigning logical addresses to VXIbus devices 
at system startup or other configuration times.

ECL

Emitter-Coupled Logic.

EEPROM

Electronically Erasable Programmable Read Only Memory.

embedded controller

An intelligent CPU (controller) interface plugged directly into the VXI 
backplane, giving it direct access to the VXIbus. It must have all of its 
required VXI interface capabilities built in.

EMC

Electromechanical Compliance.