Introduction to the Processor
September 4 (Day); August 29 (Night)
Introduction to the Processor:
oThe CPU (a.k.a. processor) is the “brain” of the computer (p. 29).
oA CPU is an electronic device that accepts input and performs some task (a.k.a.
function) based on that input. These tasks may be arithmetic (such as adding 2 + 2)
or sending an image to the video card to be displayed on the monitor (p. 29).
oThe collection of all the functions that a CPU can perform is called the CPU’s
instruction set (p. 29).
oSoftware programs and different pieces of hardware send commands to the CPU
telling it to perform a function within its instruction set (p. 29).
Relationship between CPU and RAM:
oSoftware programs are stored on the hard drive. These programs must be sent from
the hard drive to the CPU, but the hard drive is far too slow and cannot get data to the
CPU fast enough (p. 29).
oTo compensate for this problem, commands and data from software do not go
directly to the CPU, but rather are stored in random access memory (a.k.a. RAM).
This RAM is very fast and can best be thought of as short term memory (p. 29).
oData generated by the CPU must be stored somewhere and that somewhere is RAM
(p. 30).
oWhy do we not use RAM for everything (p. 30)?
Hard drives can store 1000s more data than RAM.
RAM is volatile.
All programs do not run at once.
Moving Data from RAM to the CPU:
oThe wires that connect the different components on the motherboard are known as
traces (p. 30).
oThe Northbridge is a special chip that connects RAM and the CPU and also connects
the CPU to computer’s very fastest components (p. 30).
