Zilog ZUSBOPTS - Manual (Page 488)

Glossary UM017105-0511
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Zilog Developer Studio II – ZNEO™
User Manual
B
baud. A unit of measure of transmission capacity. The speed at which a modem can transmit data. The
number of events or signal changes that occur in one second. Because one event can encode more than one
bit in high-speed digital communications, baud rate and bits per second are not always synonymous, espe-
cially at speeds above 2400 bps.
baud rate. A unit of measure of the number of state changes (from 0 to 1 or 1 to 0) per second on an asyn-
chronous communications channel.
binary (b). A number system based on 2. A binary digit is a bit.
bit. binary digit—a digit of a binary system. It contains only two possible values: 0 or 1.
block diagram. A diagram of a system, a computer, or a device in which the principal parts are repre-
sented by suitably annotated geometrical figures to show both the basic functions of the parts and their
functional relationships.
buffer. 1. In hardware, a device that restores logic drive signal levels to drive a bus or a large number of
inputs. In software, any memory structure allocated to the temporary storage of data. 2. A routine or stor-
age medium used to compensate for a difference in rate of flow of data, or time of occurrence of events,
when transferring data from one device to another.
bus. In electronics, a parallel interconnection of the internal units of a system that enables data transfer and
control information. One or more conductors or optical fibers that serve as a common connection for a
group of related devices.
byte (B). A sequence of adjacent bits (usually 8) considered as a unit. A collection of four sequential bits
of memory. Two sequential bytes (8 bits) comprise one word.
C
CALL. This command invokes a subroutine.
CCF. Clear Carry Flag.
character set. A finite set of different characters that is complete for a given purpose. A character set
might include punctuation marks or other symbols.
CIEF. Clear IE Flag.
clock. A specific cycle designed to time events, used to synchronize events in a system.
CLR. Clear.
CMOS. Complementary Metal Oxide Semiconductor. A type of integrated circuit used in processors and
for memory.
compile. 1. To translate a computer program expressed in a high-level language into a program expressed
in a lower level language, such as an intermediate language, assembly language, or a machine language.

2. To prepare a machine language program from a computer program written in another programming lan-
guage by making use of the overall logic structure of the program or by generating more than one computer
instruction for each symbolic statement as well as performing the function of an assembler.
compiler. A computer program for compiling.
COPF. Clear Overflow Protection Flag.