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8/3/2019 Over View of Microprocessor Systems
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OVER VIEW OFMICROPROCESSOR
SYSTEMS
L.ANJANEYULU
Dept of ECE
N.I.T., Warangal
OVER VIEW OFMICROPROCESSOR
SYSTEMS
L.ANJANEYULU
Dept of ECE
N.I.T., Warangal
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ENIAC-on-a-ChipMoore School of Electrical Engineering, University of
Pennsylvania http://www.ee.upenn.edu/~jan/eniacproj.html
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Intel1950's: Shockley leaves Bell Labs to establish Shockley Labs inCalifornia. Some of the best young electronic engineers and solid-state physicists come to work with him. These include Robert Noyceand Gordon Moore.1969: Intel was a tiny start-up company in Santa Clara, headed by
Noyce and Moore .1970: Busicom placed an order with Intel for custom calculator chips.Intel had no experience of custom-chip design and sets outs to design ageneral-purpose solution .1971: Intel have problems translating architectures into working chipdesigns - the project runs late.
Faggin joins Intel and solves the problems in weeks.
The result is the Intel 4000 family (later renamed MCS-4,Microcomputer System 4-bit), comprising the 4001 (2k ROM), the4002 (320-bit RAM), the 4003 (10-bit I/O shift-register) and the 4004 ,a 4-bit CPU.
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Intel 4004Introduced in 1971, the Intel4004 "Computer-on-a-Chip" wasa 2300 transistor device capableof performing 60,000 operations
per Second.
It was the first-ever single-chipmicroprocessor and hadapproximately the same
performance as the 18,000vacuum tube ENIAC. The 4-bitIntel C4004 ran at a Clock Speedof 108 Kilo Hertz.
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The Intel 4004
FedericoFaggindesigned theIntel 4004
processor.His initialswere printedon thecircuit.
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Intel 4004 ± First Microcomputer
http://uk.geocities.com/magoos_universe/4004_main.htm
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The Busicom Calculator
The Busicom calculator used five Intel 4001¶s, two4002¶s, three 4003¶s andthe 4004 CPU
The original engineering prototype
of the Busicom desk-top printingcalculator, the world¶s firstcommercial product to use a
microprocessor.
http://www.computerhistory.org/exhibits/highlights/busicom.shtml
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Intel 8008
1972: Faggin begins work on an 8 -bit processor, theIntel 8 00 8 . The prototype has serious problems withelectrical charge leaking out of its memory circuits.
Device physics, circuit design and layout are important new skills. The 8008 chip layout is completely redesignedand the chip is released.There is a sudden surge in microprocessor interest.Intel's 8008 is well-received, but system designers wantincreased speed, easier interfacing, and more I/O andinstructions. The improved version, produced by Faggin,is the 8 08 0.Faggin leaves Intel to start his own company Zilog , who
later produce the Z 8 0.
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Federico Faggin : ZilogZilog produced the3.5MHz Zilog Z80 (a very
popular processor taught
in many universities)« and, later, a 16-bit Z8000.
Another great design butZilog struggled to providegood support, they were anew and inexperiencedcompany and had only afew hundred employees;at this time Intel had over 10 thousand.
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The Zilog Z80
The Z80 microprocessor is an 8 bitCPU with a 16 bit address bus capableof direct access of 64k of memoryspace.
It was based on the 8080; it has a largeinstruction set.
Programming features include an
accumulator and six eight bit registersthat can be paired as 3-16 bit registers.In addition to the general registers, astack-pointer, program-counter, andtwo index (memory pointers) registers
are provided.
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Early Microcontrollers1974: Motorola (originally car radio manufacturers) hadintroduced transistors in the 1950s and decided to make a late
but serious effort in the microprocessor market. Theyannounced their 8-bit 68 00 processor. Though bulky, andfraught with production problems, their 6800 had a gooddesign.1975: General Motors approach Motorola about a custom-builtderivative of the 6800. Motorola's long experience withautomobile manufacturers pays off and Ford follow GM's lead.
1976: Intel introduce an 8-bit microcontroller, the MCS-48.They ship 251,000 in this year.
1980: Intel introduce the 8 051 , an 8-bit microcontroller withon-board EPROM memory. They ship 22 million and 91million in 1983.
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The Intel 8086(1978)29,000 TransistorsClock Speeds: 5, 8 and 10 MHzApprox. 10 times the
performance of the 8080 Intel8086, 16 bit ³assembly-languagecompatible´ extension of the8080 architecture. 1978.
All registers 16 bits wide.Additional registers all havededicated uses.
Ex tended Accumulator architecture.IBM selects the 8088, an 8086with an 8 bit external bus, as the
processor for the IBM PC. Early1980
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Early Computers1979: Motorola also announce a 16-bit68000. Indisputably, the best
microprocessor on the market. It would beused in the Apple Macintosh launched in1984.
Intel look seriously at the competition(Motorola and Zilog) and implement'O peration CRUSH ' - a huge campaignwith a focused and trained work force
providing customer support, completesolutions and long-term product support.
CRUSH proves an excellent strategy andthe 8086 becomes the de facto standard.This success helps finance additions to their
product range, one of which is the buswidth reduced 8 088 , a 16-bit ( 8 -bit bus)microprocessor .
The early Apple Macintosh
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The IBM PC1981: IBM, having seen Apple's success recognise
a new personal computer market. They choose Intelover Motorola and Zilog (and their own proprietary
processors) because of Intel's long-term commitmentto the 8086 line.
IBM selects the Intel 8 088 for their PC, introduced inAugust.Intel bring out the 16-bit 80286 for the IBM PC AT
but it has weaknesses, most notably in virtual memorysupport. The newest 'killer' application software,Microsoft Windows , needs a more powerful
processor.
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Contemporary Microprocessors:
16/32-bit Processors(external 16-bit Bus, internal 32 BitStructure)
Motorola MC68010
National Semiconductor NS16032 Additional Functionality on the Chip
Direct Memory Access (DMA) (Intel 80186)Virtual memory management(MC68010, Intel 80286)Optional Coprocessor (Intel 8086/80286,NS16032)Extended Address Space
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32-bit ProcessorsCISC Processors
Motorola MC680x0Intel i386 / i486 / PentiumNational Semiconductor NS32x32Concept of a Processor FamilyBinary CompatibilityCompatible with 16 Bit Processors
RISC Processors
Advanced Micro Devices Am29000 (~1987)Sun Microsystems SPARCMIPS technologies MIPS R2000 / MIPS R3000
Microprocessor History
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Moore¶s Law
Dr. Gordon E. Mooreco-founded Intel in1968.
His observation thatnumber of transistorsdoubled every 2 years
became known as´ Moore ·s Law µ
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Pentium Evolution (1)8086
much more powerful16 bitinstruction cache, prefetch few instructions8088 (8 bit external bus) used in first IBM PC
80286(1982) :Added new instructions to support memory management.Added memory mapping and multilevel protection schemeAdded real addressing mode to support legacy 8086 code.
16 Mbyte memory addressable (up from 1Mb) Include:Segment limit checking,Read-only and execute-only segment options,Up to four privilege levels to protect operating system code (inseveral subdivisions, if desired) from application or user programs.
Hardware task switching and local descriptor tables allow the operatingsystem to protect application or user programs from each other.
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80386(1985) IA-32 architecture family .Support for multitaskingAdditional registers (segment pointers).All GP registers now 32 bits.Address space now 32 bits with several new addressingmodes. Provides logical address space for eachsoftware processAdded paging support under existing segmentedarchitecture. Supports:Segmented-memory modeland³ Flat ´ one-memory model
Almost a general purpose register machine.Intel386 Processor Includes 6 Parallel Stages. Bus interface u nit , Code prefetch u nit ,In s tr u ction decodeu nit , Exec u tion u nit , Segment u nit , Paging u nit
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Intel486 processor more parallel execution capability than Intel386instruction decode and execution units in five pipelined stages,
each stage (when needed) operates in parallel with the others on upto five instructions in different stages of execution.Each stage can do its work on one instruction in one clock, and sothe Intel486 processor can execute as rapidly as one instruction per clock cycle.
8-KByte on-chip fir s t level cache to increase the percent of instructionsthat could execute at the scalar rate of one per clock:Memory access instructions included if the operand was in the first-levelcache.
Integrated the x87 floating point unit onto the processor New pins, bits and instructions to support more complex and powerfulsystems
Second-level cache supportMultiprocessor support.Power management (for notebooks and laptops
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Speeding it upPipeliningOn board cache
On board L1 & L2 cacheBranch predictionData flow analysisSpeculative execution
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Pentium Evolution (2)
80486sophisticated powerful cache and instruction pipelining
built in maths co-processor
PentiumSuperscalar Multiple instructions executed in parallel
Pentium ProIncreased superscalar organization
Aggressive register renaming branch predictiondata flow analysisspeculative execution
CPU+ L1 Cache
L2 CacheCPU+ L1 Cache
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Pentium Evolution (3)Pentium II ( 1997)Pentium Pro + MMX (MultiMedia eXtensions)
- Data Bus (64bit), Address Bus (36bit)- L1 Cache: 32K Byte, L2 Cache: 512K Byte Cache- Processor Core Speed (450MHz - 233MHz)- System Bus (100MHz)
graphics, video & audio processingCeleron = Pentium II - L2Cache - Celeron A :
L2Cache(128KByte)Xeon = Pentium II + Graphic Accelerator + .. (Server CPU) (1998)Scalability : can be scaled to 2, 4, 8 or more,
and used for high-end server and workstations
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Pentium III(1999)
- Data Bus (64bit), Address Bus (36bit)- Processor Core Speed (1.1GHz - 450MHz)- System Bus (133MHz)- Cache Speed Upgrade (Advanced Transfer Cache)- 70 New Extended Instructions (SIMD)
70 new streaming SIMD extensions (SSE) :50 to improve floating-point performance
12 to improve multimedia processing8 to improve the efficiency of L1 cache
- Pentium III Xeon ProcessorAdditional floating point instructions for 3Dgraphics
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Pentium 4 ( 2000)
Further floating point and multimedia enhancements- Data Bus (64bit), Address Bus (36bit)- Processor Core Speed (2GHz - 3.2GHz)- System Bus (400MHz-800MHz)
- 800 MHz : Pentium 4 C-3.20 GHz, 3 GHz, 2.80 GHz, 2.60 GHz, 2.40 GHz
- 533 MHz : Pentium 4 B3.06 GHz, 2.80 GHz, 2.66 GHz, 2.53 GHz, 2.40 GHz, 2.26 GHz
- 400 MHz : Pentium 4 A2.60 GHz, 2.50 GHz, 2.40 GHz, 2.20 GHz, 2 GHz
-hyper-threading technologyItanium
64 bitSee Intel web pages for detailed information on processors
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Technological Development
420000002000Pentium 4
240000001999Pentium-III
75000001997Pentium-II
31000001993Pentium
1180000198980486
275000198580386
120000198280286
2900019788086500019748080
250019728008
225019714004
# of tran s is tor s Year Model
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Technological Development
1000
10000
100000
1000000
10000000
100000000
1 9 7 1
1 9 7 2
1 9 7 4
1 9 7 8
1 9 8 2
1 9 8 5
1 9 8 9
1 9 9 3
1 9 9 7
1 9 9 9
2 0 0 0
Y ear
# o
f t r a n s
i s t o r s
4004
8008
8080
8086
8028680386
80486 Penti u m
Penti u m IIPenti u m III
Penti u m 4
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Performance
4004 8 00 8 8 08 0 8 08 6 8 088
Introduced 1971 1972 1974 1978 1979
Clock Speeds
108 KHz 108 KHz 2 MHz 5 MHz,8MHz,10MHz
5 MHz,8MHz
Bus Width 4 bits 8 bits 8 bits 16 bits 8 bits
Number of
Transistors
2300 3500 6000 29,000 29,000
AddressableMemory
640 bytes 16 KBytes 64 KBytes 1 MB 1 MB
VirtualMemory
-- -- -- -- --
1970s Processors:
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Performance
8 02 8 6 3 8 6TM DX 3 8 6TM SX 4 8 6TM DXCPU
Introduced 1982 1985 1988 1989
Clock Speeds 6 MHz ±
12.5 MHz 16 MHz-33MHz 16 MHz-33MHz 25 MHz- 50MHz
Bus Width 16 bits 32 bits 16 bits 32 bits
Number of Transistors 134,000 275,000 275,000 1.2 million
AddressableMemory
16 MB 4 GB 4GB 4GB
Virtual
Memory
1 GB 64 TB 64 TB 64 TB
19 8 0s Processors:
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Performance
48 6TM SX Pentium Pentium Pentium II
Introduced 1991 1993 1995 1997
Clock Speeds
16 MHz-133MHz
60 MHz ± 166 MHz
150 MHz-200MHz
200 MHz-300MHz
Bus Width 32 bits 32 bits 64 bits 64 bits
Number of Transistors
1.185 million 3.1 million 5.5 million 7.5 million
AddressableMemory
4 GB 4 GB 64 GB 64 GB
VirtualMemory
64 TB 64TB 64 TB 64 TB
1990s Processors:
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Performance
Pentium III Pentium 4
Introduced 1999 2000
Clock Speeds
450 MHz 1.3-1.8 GHz
Bus Width 64 bits 64 bits
Number of Transistors
95 million 42 million
AddressableMemory
64 GB 64 GB
VirtualMemory
64 GB 64 TB
Recent Processors:
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Contemporary Microprocessor
64/32-bit ProcessorsSUN Microsystems SuperSPARCMotorola 88110IBM, Motorola PowerPC 601 (MPC601)
³ Modern ´ Processors64-bit StructureInternal Parallelism
Instruction pipeliningArithmetic Pipelining
Instruction and Data Caches Advanced Memory and PeripheralConnections
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Performance Mismatch
Processor speed increasedMemory capacity increased
Memory speed lags behind processor speed!!
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DRAM and Processor Characteristics
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Intel Itanium 2 (McKinley)
64bit Processor 221 million transistors!
How are they used?What will we do astransistor countscontinue to grow?Most of chip is used for memories, inst. decoding,dynamic scheduling«
Why is it done this way?How much more efficientcould it be if more of areawent to actual processing?
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Even More Recent Example
Runs 64-bitIA-64 ISA
Die: 3.74 cm 2
.13µ process410M transistors1.5GHz core1.3V logic130W power
consumption!
6.4GB/s busCost: $2,247-
$4,2269MB L3 cachelater this year«
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AMD Opteron (100 Million Transistors)
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Cyrix IIIDeveloped by National Semiconductor 133 MHz Front Side Bus (although it supports 66 MHz, and 100 MHz FSB).256 KB integrated L2 cache along with a 64 KB integrated L1 cache.3dNow! SIMD instructions in a dual pipelined FPU.
As with the MII, the Cyrix III supports MMX.superscalar design featuring two seven stage pipelines allowing two processing streams to be processed simultaneously.two level translation buffer and a 512 entry branch target buffer.out-of-order execution through register renaming and data forwarding and
bypassing to resolve data dependencies between pipelines.Speculative execution after a predicted branch is also supported.15% to 20% cheaper than a comparable Celeron.Hope to capture 10% of market.Subject of a lot of legal action by Intel but VIA is still in business.
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First Implementation of Key Features: Montecito
Power Management/
FrequencyBoost
(Foxton)
1MB L2I1MB L2I
Dual-core
2x12MB L32x12MB L3cachescaches
withwithPellstonPellston
2 Way2 WayMultiMulti- -threadingthreading
Arbiter Arbiter
9 0 nm9 0 nm
1 .7 Billion1 .7 Billion
TransistorsTransistors
Key Processor FeaturesIntel¶s first dual-coreprocessor Intel¶s first processor
with >1 billion transistors24 MB L3 cacheMulti-threadingCompatible with existingItanium 2-based systems
Targeting H2¶2005
Sy s tem Bus
Core
L3 Cache
Core
L3 Cache
Sy s tem Bus
Core
L3 Cache
Core
L3 Cache
Core 1 Core 2
Mu ltiple core s , Mu ltiple thread s Mu ltiple core s , Mu ltiple thread s and L 3 Cache on ONE dieand L 3 Cache on ONE die
Mu ltiple core s , Mu ltiple thread s Mu ltiple core s , Mu ltiple thread s and L 3 Cache on ONE dieand L 3 Cache on ONE die
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Intel¶s Latest: The Pentium 4 2.4GHz
478 pin packaging
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Selecting a Microprocessor Issues
Technical: speed, power, size, costOther: development environment, prior expertise, licensing, etc.
Speed: how evaluate a processor¶s speed?Clock speed ± but instructions per cycle may differ Instructions per second ± but work per instr. may differ
Dhrystone: Synthetic benchmark, developed in 1984.Dhrystones/sec.
MIPS: 1 MIPS = 1757 Dhrystones per second (based onDigital¶s VAX 11/780). A.k.a. Dhrystone MIPS. Commonlyused today.
So, 750 MIPS = 750*1757 = 1,317,750 Dhrystones per second
SPEC: set of more realistic benchmarks, but oriented to desktopsEEMBC ± EDN Embedded Benchmark Consortium,www.eembc.org
Suites of benchmarks: automotive, consumer electronics,
networking, office automation, telecommunications
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Which has higher performance?Time to do the task (Execution Time)
execution time, response time, latencyTasks per day, hour, week, sec, ns. .. (Performance)throughput, bandwidth
Response time and throughput often are in oppositionResponse Time
Time to complete a task Throughput
Total amount of work done per timeExecution Time (CPU Time)
User CPU timeTime spent in the program
System CPU timeTime spent in OS
Elapsed TimeExecution Time + Time of I/O and time sharing
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Criteria of PerformanceExecution time seems to measure the power of theCPUElapsed time measures the performance of wholesystem including OS and I/OUser is interested in elapsed timeSales people are interested in the highest number of performance that can be quotedPerformance analysist is interested in bothexecution time and elapsed time
Performance evaluationPerformance evaluation