A Brief History of Microprocessors

Module M13.1

Sections 1.1, 9.1

Some Microprocessors

• Intel 4004

• Intel 8080

• Motorola 6800

• MOS Technology 6502

• Intel 8088/8086

• Motorola 6809

• Motorola 68000

• Motorola 6811/12

A Typical Computer System

CPU(8086 Microprocessor)

INPUT(Keyboard)

OUTPUT(Screen)

MEMORY

RAM ROM

EXTERNALSTORAGE

(Disks)

Table 1.2History of Microprocessors

Date Microprocessor Comment1971 Intel 4004 First microprocessor (4 bits)1972 Intel 8008 First 8-bit microprocessor1974 Intel 80801975 Motorola 6800 5 volts only (1 MHz)1976 MOS Technology 6502 Used in Apple II, PET, Atari1977 Motorola 6802 128-byte internal RAM1978 Motorola 6801 Single-chip microcomputer1978 Intel 8086/8088 40,000 Transistors (16-bit data)1979 Motorola 68000 68,000 Transistors1979 Motorola 68701 MCU_EPROM–I/O1979 Motorola 6805 Low-cost microcontroller1979 Motorola 6809 Used in TRS-80 color computer1981 IBM PC, uses Intel 80881982 Motorola 680101982 Motorola 680081984 Intel 80286 10 MHz, 130,000 transistors1984 Motorola 68020 32-Bit address and data busses1985 Motorola 68020 -- 20 MHz1986 Motorola 68020 -- 25 MHz1986 Intel 80386 16 MHz, 275,000 transistors1987 Motorola 680301988 Motorola 68030 -- 33 MHz1989 Intel 80486 25 MHz, 1,000,000 transistors1990 Intel 80486 50 MHz1992 Intel 80586 4,000,000 Transistors

1995 Intel 80686 22,000,000 Transistors2000 Intel 80786 100,000,000 Transistors (250 MHz)

Table 1.2History of Microprocessors

Date Microprocessor Comment1971 Intel 4004 First microprocessor (4 bits)1972 Intel 8008 First 8-bit microprocessor1974 Intel 80801975 Motorola 6800 5 volts only (1 MHz)1976 MOS Technology 6502 Used in Apple II, PET, Atari1977 Motorola 6802 128-byte internal RAM1978 Motorola 6801 Single-chip microcomputer1978 Intel 8086/8088 40,000 Transistors (16-bit data)1979 Motorola 68000 68,000 Transistors1979 Motorola 68701 MCU_EPROM–I/O1979 Motorola 6805 Low-cost microcontroller1979 Motorola 6809 Used in TRS-80 color computer1981 IBM PC, uses Intel 8088

Table 1.2History of Microprocessors

Date Microprocessor Comment1971 Intel 4004 First microprocessor (4 bits)1972 Intel 8008 First 8-bit microprocessor1974 Intel 80801975 Motorola 6800 5 volts only (1 MHz)1976 MOS Technology 6502 Used in Apple II, PET, Atari1977 Motorola 6802 128-byte internal RAM1978 Motorola 6801 Single-chip microcomputer1978 Intel 8086/8088 40,000 Transistors (16-bit data)1979 Motorola 68000 68,000 Transistors1979 Motorola 68701 MCU_EPROM–I/O1979 Motorola 6805 Low-cost microcontroller1979 Motorola 6809 Used in TRS-80 color computer1981 IBM PC, uses Intel 8088

The 8080 Microprocessor

• 40-pin chip

• Developed by Intel in 1974

• 16 Address Lines– Can address 216 = 64 Kbytes of memory

• 8 Data Lines

• Required +5V, +12V and -5V

• First microprocessor to become widely used

The 8080 Microprocessor

PSWACEL

BDH

SPPC

Program Status WordPrimary AccumulatorSecondary Accumlators/ Data Counters

Stack PointerProgram Counter

Table 1.2History of Microprocessors

Date Microprocessor Comment1971 Intel 4004 First microprocessor (4 bits)1972 Intel 8008 First 8-bit microprocessor1974 Intel 80801975 Motorola 6800 5 volts only (1 MHz)1976 MOS Technology 6502 Used in Apple II, PET, Atari1977 Motorola 6802 128-byte internal RAM1978 Motorola 6801 Single-chip microcomputer1978 Intel 8086/8088 40,000 Transistors (16-bit data)1979 Motorola 68000 68,000 Transistors1979 Motorola 68701 MCU_EPROM–I/O1979 Motorola 6805 Low-cost microcontroller1979 Motorola 6809 Used in TRS-80 color computer1981 IBM PC, uses Intel 8088

The 6800 Microprocessor

• 40-pin chip

• Developed by Motorola in 1975

• 16 address lines and 8 data lines

• Used only +5V

The 6800 MicroprocessorRegisters

A

B

X

PC

SP

CC

Accumulator AAccumulator BIndex register XProgram counterStack pointerCondition code register

Table 1.2History of Microprocessors

Date Microprocessor Comment1971 Intel 4004 First microprocessor (4 bits)1972 Intel 8008 First 8-bit microprocessor1974 Intel 80801975 Motorola 6800 5 volts only (1 MHz)1976 MOS Technology 6502 Used in Apple II, PET, Atari1977 Motorola 6802 128-byte internal RAM1978 Motorola 6801 Single-chip microcomputer1978 Intel 8086/8088 40,000 Transistors (16-bit data)1979 Motorola 68000 68,000 Transistors1979 Motorola 68701 MCU_EPROM–I/O1979 Motorola 6805 Low-cost microcontroller1979 Motorola 6809 Used in TRS-80 color computer1981 IBM PC, uses Intel 8088

The 6502 Microprocessor

• 40-pin chip

• Developed by MOS Technology, Inc. in 1976

• 16 address lines and 8 data lines

• Based on the Motorola 6800

• Used in many home computers including the– Apple II– Commodore PET– Atari

The 6502 MicroprocessorRegisters

A

X

Y

PC

SP

Status

AccumulatorIndex register XIndex register YProgram counterStack pointerStatus register

Table 1.2History of Microprocessors

Date Microprocessor Comment1971 Intel 4004 First microprocessor (4 bits)1972 Intel 8008 First 8-bit microprocessor1974 Intel 80801975 Motorola 6800 5 volts only (1 MHz)1976 MOS Technology 6502 Used in Apple II, PET, Atari1977 Motorola 6802 128-byte internal RAM1978 Motorola 6801 Single-chip microcomputer1978 Intel 8086/8088 40,000 Transistors (16-bit data)1979 Motorola 68000 68,000 Transistors1979 Motorola 68701 MCU_EPROM–I/O1979 Motorola 6805 Low-cost microcontroller1979 Motorola 6809 Used in TRS-80 color computer1981 IBM PC, uses Intel 8088

The 8088/8086 Microprocessor

• 40-pin chip

• Developed by Intel in 1978

• 20 address lines – Can address 220 = 1 Mbyte of memory

• 8/16 multiplexed data lines in 8088/8086

• 8088 used in the first IBM PC in 1981

8086 RegistersAX

BX

AH

DX

CX

AL

BH BL

CH CL

DH DL

SI

DI

BP

SP

IP

SF

CS

DS

ES

SS

Source

Destination Index Registers

General Registers

Pointer Regsiters

Status Flags

Segment Registers

Base

Stack

Instruction

Code

Data

Extra

Stack

Table 1.2History of Microprocessors

Date Microprocessor Comment1971 Intel 4004 First microprocessor (4 bits)1972 Intel 8008 First 8-bit microprocessor1974 Intel 80801975 Motorola 6800 5 volts only (1 MHz)1976 MOS Technology 6502 Used in Apple II, PET, Atari1977 Motorola 6802 128-byte internal RAM1978 Motorola 6801 Single-chip microcomputer1978 Intel 8086/8088 40,000 Transistors (16-bit data)1979 Motorola 68000 68,000 Transistors1979 Motorola 68701 MCU_EPROM–I/O1979 Motorola 6805 Low-cost microcontroller1979 Motorola 6809 Used in TRS-80 color computer1981 IBM PC, uses Intel 8088

The 6809 Microprocessor

• 40-pin chip

• Developed by Motorola in 1979

• 16 address lines and 8 data lines

• Used in the Radio Shack Color Computer

• Widely used in industrial controllers

The 6809 MicroprocessorRegisters

A B

Y

S

U

DP

Accumulator A:B = DIndex register XIndex register YSystem stack pointerUser stack pointerProgram counterDirect page registerCondition code register

X

CC

PC

Table 1.2History of Microprocessors

Date Microprocessor Comment1971 Intel 4004 First microprocessor (4 bits)1972 Intel 8008 First 8-bit microprocessor1974 Intel 80801975 Motorola 6800 5 volts only (1 MHz)1976 MOS Technology 6502 Used in Apple II, PET, Atari1977 Motorola 6802 128-byte internal RAM1978 Motorola 6801 Single-chip microcomputer1978 Intel 8086/8088 40,000 Transistors (16-bit data)1979 Motorola 68000 68,000 Transistors1979 Motorola 68701 MCU_EPROM–I/O1979 Motorola 6805 Low-cost microcontroller1979 Motorola 6809 Used in TRS-80 color computer1981 IBM PC, uses Intel 8088

The 68000 Microprocessor

• 64-pin chip

• Developed by Motorola in 1979

• 24 address lines – Can address 224 = 16 Mbytes of memory

• 16 data lines

• Used in the original Macintosh Computer

The 68000 MicroprocessorRegisters31 16 15 8 7 0

D0D1D2D3D4D5D6D7

DataRegisters

31 16 15 0A0A1A2A3A4A5A6A7 A7’

AddressRegisters

Program Counter

Status/CCR

Table 1.2History of Microprocessors

Date Microprocessor Comment

1981 IBM PC, uses Intel 80881982 Motorola 680101982 Motorola 680081984 Intel 80286 10 MHz, 130,000 transistors1984 Motorola 68020 32-Bit address and data busses

Integrated Microcontroller1985 Motorola 68HC111986 Motorola 68020 -- 25 MHz1986 Intel 80386 16 MHz, 275,000 transistors1987 Motorola 680301988 Motorola 68030 -- 33 MHz1989 Intel 80486 25 MHz, 1,000,000 transistors1990 Intel 80486 50 MHz1992 Intel Pentium 4,000,000 Transistors1997 Motorola 68HC12 Enhanced 68HC11

The 68HC11/12

RAM CPU EEPROMROM/ EPROM

TIMER

PARALLEL I/O SPI SCI

A/D68HC11/12

The 68HC12(11) Registers

S X H I N Z V C

A B

D

IX

IY

SP

PC

Accum ulator A

Accum ulator D

Inde x register X

Inde x register Y

Sta ck Pointer

Pro gra m counter

Condition code register

Accum ulator B