1.Introduction to microprocessors

Digital Computer• Multipurpose programmable machine that reads

binary information from its memory accepts binary data as its input and processes data according to instructions and provides results as output

Input

Memory

CPU

Output

Microcomputer

• The CPU is replaced by the microprocessor

Reg. Array

Control

Input Output

ROM R/WM

Microprocessor Memory

System Bus

ALUReg.Array

Control Unit

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Microprocessor

• Microprocessor is a programmable logic device designed with registers, flip flops and timing elements.

• General-purpose microprocessor

CPU for Computers

Example： Intel’s x86, Motorola’s 680x0

CPU

(Micro-processor)

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Microcontroller

• A smaller computer• On-chip RAM, ROM, I/O ports... • Example：Motorola’s 6811, Intel’s 8051,

Zilog’s Z8 and PIC 16X

RAM ROM

I/O Port

TimerSerial COM Port

CPU

A single chip Microcontroller

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Microprocessor CPU is stand-alone, RAM,

ROM, I/O, timer are separate designer can decide on the

amount of ROM, RAM and I/O ports.

expensive versatility general-purpose

Microcontroller• CPU, RAM, ROM, I/O and

timer are all on a single chip• fix amount of on-chip ROM,

RAM, I/O ports• Highly bit addressable• for applications in which cost,

power and space are critical• single-purpose

Microprocessor vs. Microcontroller