Glossary
Getting Started with Your VXIpc-850 G-2 © National Instruments Corporation
address space A set of 2n memory locations differentiated from other such sets
in VXI/VMEbus systems by six addressing lines known as
address modifiers. n is the number of address lines required to
uniquely specify a byte location in a given space. Valid numbers
for n are 16, 24, and 32. In VME/VXI, because there are six
address modifiers, there are 64 possible address spaces.
address window A portion of address space that can be accessed from the
application program.
ANSI American National Standards Institute
ASIC application-specific integrated circuit
B
B bytes
backplane An assembly, typically a printed circuit board, with 96-pin
connectors and signal paths that bus the connector pins. A C-size
VXIbus system will have two sets of bused connectors called J1
and J2. A D-size VXIbus system will have three sets of bused
connectors called J1, J2, and J3.
BIOS Basic Input/Output System. BIOS functions are the fundamental
level of any PC or compatible computer. BIOS functions
embody the basic operations needed for successful use of the
computer’s hardware resources.
Bus Timeout Unit A functional module that times the duration of each data transfer
and terminates the cycle if the duration is excessive. Without the
termination capability of this module, a bus master attempt to
access a nonexistent slave could result in an indefinitely long
wait for a slave response.
byte order How bytes are arranged within a word or how words are
arranged within a longword. Motorola ordering stores the most
significant (MSB) byte or word first, followed by the least
significant byte (LSB) or word. Intel ordering stores the LSB or
word first, followed by the MSB or word.