Page 182 - Bebop to The Boolean Boogie An Unconventional Guide to Electronics Fundamentals, Components, and Processes

Memory ICs w 163

The brain of the computer is the central processing unit (CPU) , which is
where all of the number crunching and decision-making are performed. The
CPU uses a set of signals called the address bus to point to the memory location
in which it is interested. The address bus is said to be unidirectional because it
conveys information in only one direction: from the CPU to the memory. By
means of control signals, the CPU either reads data from, or writes data to, the
selected memory location. The data is transferred on a set of signals called the
data bus, which is said to be bidirectional because it can convey information in
two directions: from the CPU to the memory and vice versa.
The bulk storage is often based on magnetic media such as a disk or tape,'
which can be used to store a large quantity of information relatively cheaply.
Because magnetic media maintains its data when power is removed from the
system it is said to be nonuohtile.

k micros, meaning "small" (in
system that can accept information conversation you always use the full
names for these devices and never try
keyboard, mouse, sensor, or to pronounce their abbreviations).
other input device), process Digital signal processing refers to
the branch of electronics concerned
on the results of this processin with the representation and manipula-
tion of signals in digital form. These
outside world in its new form (usi signals include voice and video, and
a computer screen, a robot arm, o this form of processing appears in such
some other output device). things as compressing and decom-
The concept of a general-pu pressing audio and video data, tele-
computer on a single chip (or on a communications, radar, and image
group of related chips called a chip processing (including medical imag-
became known as a microprocessor. ing). A digital signal processor (DSP) is
(A microcontroller may be considere a special form of microprocessor that
be a microprocessor augmented with has been designed to perform a
special-purpose inputs, outputs, and specific processing task on a specific
control logic like counter-timers). T type of digital data much faster and
written abbreviations for microproces- more efficiently than can be achieved
sors and microcontrollers are pP and using a general-purpose device. (In
pC, respectively, where "p", pro- conversation, DSP is always spelled out
nounced "mu" for "micro" come as "D-S-P").

2 The use of tape is becoming increasingly rare for almost any form of mainstream application.