National Instruments VXI/VME 600 - Manual (Page 50)

Glossary
VXI/VMEpc 600 Series for Windows 95/NT G-2 © National Instruments Corporation
ANSI American National Standards Institute
API Application Programming Interface; the direct interface that an end user
sees when creating an application
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.
BERR* Bus error signal
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.
BTO See Bus Timeout Unit.
bus error An error that signals failed access to an address. Bus errors occur with
low-level accesses to memory and usually involve hardware with bus
mapping capabilities. For example, nonexistent memory, a nonexistent
register, or an incorrect device access can cause a bus error.
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.