3 Evolution of Computers Upto 8088
Transcript of 3 Evolution of Computers Upto 8088
-
8/22/2019 3 Evolution of Computers Upto 8088
1/26
Evolution of ComputersEvolution of Computers
Up to IBM PC/Intel 8088Up to IBM PC/Intel 8088
By
Prof. Dr. Shaiq A. HaqChairman CSE Department
University of Engineering & Technology, Lahore
-
8/22/2019 3 Evolution of Computers Upto 8088
2/26
Scheme of PresentationScheme of Presentation
Von Neumann Architecture
Architecture of Intel Microprocessors;
4004 (1971, 4-bit, 4KB address space)
8008 (1972, 8-bit, 4KB address space)
4040 (1974, 4-bit, 8KB address space)
8080 (1974, 8-bit, 64KB address space)
8085 (1975, 8-bit, 5 volt version)
8086/8088 (1978, 16-bit, 1MB address space)
-
8/22/2019 3 Evolution of Computers Upto 8088
3/26
Von Neumann ArchitectureVon Neumann Architecture
An architecture referred to computing machines in1945, having Memory, Instruction Decoder, Control
Unit, ALU, Data Paths/Bus. The idea of Stored Program was first introduced in
1936 by konrad Zuse in a Patent application but the
credit of architecture goes to Von neumann. Separation of Storage from Processing Unit
Sequential (Fetch-Decode-Execute) cycle
Common bus for instruction and data
A stored-program design also lets programs modifythemselves while running.
-
8/22/2019 3 Evolution of Computers Upto 8088
4/26
Von Neumann ArchitectureVon Neumann Architecture
The separation between the CPU, Memory and I/O devicesleads to what is known as the von Neumann bottleneck.
-
8/22/2019 3 Evolution of Computers Upto 8088
5/26
Modern Computer ArchitectureModern Computer Architecture
MemoryMemory(Stored Program Instructions)
InstructionInstructionDecoderDecoder
Control UnitControl Unit
ALU
I/O DevicesI/O Devices
IRIR
PCPC
ACCUMULATOR
-
8/22/2019 3 Evolution of Computers Upto 8088
6/26
Harvard ArchitectureHarvard Architecture
In Harvard Architecture two separate
memories are used for instructions and data
instead of a single memory.
Harvard Architecture vs. Princeton
Architecture.
Shared Bus Architecture vs. Independent
Bus Architecture.
-
8/22/2019 3 Evolution of Computers Upto 8088
7/26
Architecture of Intel 4004Architecture of Intel 4004
The Intel 4004, a 4-bit central processingunit (CPU), released by Intel Corp. in 1971,
is widely considered to be the worlds firstcommercial single chip microprocessor.
Based on Harvard Architecture
4-bit data bus, 12-bit program address,which allowed 4 KB memory access from
the 4-bit address bus if all 16 RAMs wereinstalled.
16- registers
8-bit instructions (46 instructions, 5 16-bit)
http://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.png -
8/22/2019 3 Evolution of Computers Upto 8088
8/26
Intel 4004Intel 4004
2,300 transistors
16-pin CERDIP
Maximum clock
speed 740 KHz.
A collectors item
In 2006, $1,000per chip on eBay
http://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.pnghttp://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.pnghttp://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.pnghttp://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.pnghttp://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.pnghttp://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.pnghttp://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.pnghttp://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.pnghttp://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.pnghttp://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.pnghttp://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.pnghttp://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.pnghttp://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.pnghttp://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.pnghttp://upload.wikimedia.org/wikipedia/commons/1/10/4004_dil.pnghttp://upload.wikimedia.org/wikipedia/commons/b/b4/4004_arch.png -
8/22/2019 3 Evolution of Computers Upto 8088
9/26
Intel 4004 ArchitectureIntel 4004 Architecture
http://upload.wikimedia.org/wikipedia/commons/b/b4/4004_arch.pnghttp://upload.wikimedia.org/wikipedia/commons/b/b4/4004_arch.pnghttp://upload.wikimedia.org/wikipedia/commons/b/b4/4004_arch.png -
8/22/2019 3 Evolution of Computers Upto 8088
10/26
Intel 8008Intel 8008
Introduced in 1972.
8-bit single bus, 18-pin DIP package.
3,300 transistors.
Initial versions of the 8008 ran at 0.5 MHz, later
increased to 0.8 MHz. Although slower than 4004 yet 8008 processed 8-
data bits at a time and could access significantly
more RAM actually gave it 3 to 4 times the true
processing power of the 4-bit chips.
Intels later CISC design heavily based on 8008.
-
8/22/2019 3 Evolution of Computers Upto 8088
11/26
Intel 4040Intel 4040
The Intel 4040 microprocessor was the successorto the Intel 4004. It was introduced in 1974.
The 4040 was used primarily in games, test,development, and control equipment.
The package of the 4040 is more than twice as
wide as the 4004 and has 24 pins vs. the 16 of the4004.
The 4040 added 14 instructions, larger stack (8
level), 8K program space, 8 more registers, andinterrupt abilities (including shadows of the first 8registers).
-
8/22/2019 3 Evolution of Computers Upto 8088
12/26
Intel 8080Intel 8080
First truly usable microprocessor CPU design.
This 8-bit CPU was released in April 1974.
Clock speed 2 MHz. Available in 40-pin DIP. Used the same instruction set of 8008.
8-bit data bus, 16-bit address bus (64KB)
Seven 8-bit registers, six of which could becombined into three 16-bit register pairs (BC, DEand HL). It also had the 8-bit Accumulator, the 16-
bit Stack Pointer to memory (replacing the 8008'sinternal Stack), and a 16-bit Program Counter.
All processor commands were coded by one byte,but some of them were followed by one or two bytes
of data, a memory address, or a port number.
-
8/22/2019 3 Evolution of Computers Upto 8088
13/26
Intel 8080Intel 8080
The 8080 IC was manufactured by NMOS
technology using a pitch of 6m.
About 6,000 transistors, die size 20mm2.
This CPU formed the basis of computers
running CP/M operating system (just like
8088 and DOS combination in 80s).
-
8/22/2019 3 Evolution of Computers Upto 8088
14/26
Intel 8085Intel 8085
Introduced in 1975, binary compatible with
8080.
The "5" in the model number came from the
fact that the 8085 required only a +5 volt
power supply rather than the +5V, -5V and+12V supplies the 8080 needed.
Available in 40-pin DIP. 8-bit data bus, 16-bit address bus.
-
8/22/2019 3 Evolution of Computers Upto 8088
15/26
MooreMoores Laws LawAfter every 18 months the number of transistors on a chip doubleAfter every 18 months the number of transistors on a chip double..
-
8/22/2019 3 Evolution of Computers Upto 8088
16/26
Intel 8086/8088 MicroprocessorsIntel 8086/8088 Microprocessors
Intel 8086 and 8088 Microprocessors are
the basis of all IBM-PC compatible
computers (8086 introduced in 1978, first
IBM-PC released in 1981)
All Intel, AMD and other advancedmicroprocessors are based on and are
compatible with the original 8086/88. At Power Up and Reset time, Pentiums,
Athlons etc all look like 8086 processors.
-
8/22/2019 3 Evolution of Computers Upto 8088
17/26
Intel 8086/8088 MicroprocessorsIntel 8086/8088 Microprocessors
Intel 8086 is a 16 bit microprocessor:
16b data registers, 16b ALU
Width of external data bus:
8086: 16 bit
8088: 8 bit Width of external address bus: 16b+4b=20b
Segment: Offset memory model Little-Endian Data Format
-
8/22/2019 3 Evolution of Computers Upto 8088
18/26
8086/8088 (1)8086/8088 (1)
Original IBM PC used 8088 microprocessor
8088 is similar to the 8086, but it has anexternal 8b data bus & only 4B-deep queue
For cost reduction reasons
We can consider 8086 and 8088 together PC clones often used 8086 for better
performance
8-bit bus reduces performance, but meantcheaper computers
-
8/22/2019 3 Evolution of Computers Upto 8088
19/26
8086/8088 (2)8086/8088 (2)
Remember the Fetch-Decode-Execute cycle?
Fetching from EXTERNAL MEMORY isSLOW.
The 8086/88 used an instruction queue to
speed up performance.
While the processor is decoding and
executing an instruction, its bus interface canbe reading new instructions, since at that time
the bus is not actually in use.
-
8/22/2019 3 Evolution of Computers Upto 8088
20/26
8086/8088 (3)8086/8088 (3)
8086/8088 consists of two internal units
The execution unit (EU) - executes the
instructions
The bus interface unit (BIU) - fetches
instructions, reads operands and writes results The 8086 has a 6B prefetch queue.
The 8088 has a 4B prefetch queue.
-
8/22/2019 3 Evolution of Computers Upto 8088
21/26
Intel 8086Intel 8086
Temporary
Registers
ALU
Flags
EUControl
AH AL
BH BL
CH CL
DH DL
SP
BP
DI
BI
CS
DS
SS
ES
IO
InternalCommunications
Registers
SUMMATION
Address Bus 20 bits
Data Bus
BusControl
1 2 3 4
Instruction Queue
8088Bus
EU BIU
I PI P
-
8/22/2019 3 Evolution of Computers Upto 8088
22/26
BIU ElementsBIU Elements
Instruction Queue: the next instructions or data can befetched from memory while the processor is executingthe current instruction
The memory interface is slower than the processorexecution time so this speeds up overallperformance
Segment Registers:
CS, DS, SS and ES are 16b registers used with the16 bit Base registers to generate the 20b address
Allow the 8086/8088 to address 1MB of memory
Changed under program control to point todifferent segments as a program executes
Instruction Pointer (IP) contains the Offset Address of
the next instruction, the distance in bytes from theaddress given by the current CS register
MAXIMUM
MODE
MINIMUM
MODE
-
8/22/2019 3 Evolution of Computers Upto 8088
23/26
MODE MODE
1 40
20 21
8086
GND
AD14
AD13
AD12
AD11
AD10
AD9AD8
AD7
AD6
AD5
AD4
AD3
AD2
AD1
AD0
NMI
INTR
CLK
GND
Vcc
AD15
A16,S3
A17,S4
A18,S5
A19,S6
/BHE,S7MN,/MX
/RD
/RQ,/GT0
/LOCK
/S2
/S1
/S0
QS0
QS1
/TEST
READY
RESET
/RQ,/GT1
HOLD
/WR
IO/M
DT/R
/DEN
ALE
/INTA
HLDA
-
8/22/2019 3 Evolution of Computers Upto 8088
24/26
74LS245
x2
8284A
Clock
Generator
RDY
Vcc
8086
CPU
CLK
READY
RESET
MN/MX#
S0#
S1#
S2#
8288
Bus
Controller
MRDC#MWTC#
AMWC#
IORC#
IOWC#
AIOWC#
INTA#
CLK
74LS373
x3ADDR/DATA
LE
OE#
ALE
DENDT/R#
BHE#
AD15:AD0
A19:A16
74LS245
x2
EN#
DIR
D15:D0
A19:A0,
BHE#
ADDR/Data
INTR
i8086 Circuit - Maximum Mode
-
8/22/2019 3 Evolution of Computers Upto 8088
25/26
Flag RegistersFlag Registers
The 8086 has 9 flags, the 80286 has 11 flags, and the80386 has 13 flags. All of these flag registers include 6flags related to data conditions (sign, zero, carry, auxiliary
carry, overflow, and parity) and three flags related tomachine operations (Interrupt, Single-step and Strings).The 80286 has two additional flags: I/O Privilege andNested Task. The I/O Privilege uses two bits in protectedmode to determine which I/O instructions can be used, andthe nested task is used to show a link between two tasks.
The processor also includes control registers and system
address registers, debug and test registers for system anddebugging operations.
/
-
8/22/2019 3 Evolution of Computers Upto 8088
26/26
8086/8088 Summary8086/8088 Summary
First Generation (introduced June 1978)
One of the first 16b processors on the
market
16b internal registers
16/8b external data bus
20b address bus (1MB addressable)
Used in 1st generation IBM PCs (1981)