CS152
Computer Architecture and Engineering
Lecture 1
Introduction and Five Components of a Computer
January 22, 2003
John Kubiatowicz (www.cs.berkeley.edu/~kubitron)
lecture slides: http://inst.eecs.berkeley.edu/~cs152/
1/22/03
©UCB Spring 2003
CS152 / Kubiatowicz
Lec1.1
Overview
° Intro to Computer Architecture (30 minutes)
° Administrative Matters (5 minutes)
° Course Style, Philosophy and Structure (15 min)
° Break (5 min)
° Organization and Anatomy of a Computer (25) min)
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What is “Computer Architecture”
Computer Architecture =
Instruction Set Architecture +
Machine Organization + …..
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Instruction Set Architecture (subset of Computer Arch.)
... the attributes of a [computing] system as seen by
the programmer, i.e. the conceptual structure and
functional behavior, as distinct from the organization
of the data flows and controls the logic design, and
the physical implementation.
– Amdahl, Blaaw, and Brooks, 1964
-- Organization of Programmable
Storage
SOFTWARE
-- Data Types & Data Structures:
Encodings & Representations
-- Instruction Set
-- Instruction Formats
-- Modes of Addressing and Accessing Data Items and Instructions
-- Exceptional Conditions
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Computer Architecture’s Changing Definition
° 1950s to 1960s: Computer Architecture Course:
Computer Arithmetic
° 1970s to mid 1980s: Computer Architecture Course:
Instruction Set Design, especially ISA appropriate
for compilers
° 1990s: Computer Architecture Course:
Design of CPU, memory system, I/O system,
Multiprocessors, Networks
° 2010s: Computer Architecture Course: Self adapting
systems? Self organizing structures?
DNA Systems/Quantum Computing?
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The Instruction Set: a Critical Interface
software
instruction set
hardware
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Example ISAs (Instruction Set Architectures)
° Digital Alpha
(v1, v3)
1992-97
° HP PA-RISC
(v1.1, v2.0)
1986-96
° Sun Sparc
(v8, v9)
1987-95
° SGI MIPS
(MIPS I, II, III, IV, V)
1986-96
° Intel
(8086,80286,80386,
80486,Pentium, MMX, ...)
1978-96
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MIPS R3000 Instruction Set Architecture (Summary)
Registers
° Instruction Categories
•
•
•
•
•
•
Load/Store
Computational
Jump and Branch
Floating Point
- coprocessor
Memory Management
Special
R0 - R31
PC
HI
LO
3 Instruction Formats: all 32 bits wide
OP
rs
rt
OP
rs
rt
OP
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rd
sa
funct
immediate
jump target
©UCBfamiliar
Spring 2003
Q: How many already
with MIPS ISA?
CS152 / Kubiatowicz
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Organization
° Capabilities & Performance
Characteristics of Principal
Functional Units
• (e.g., Registers, ALU, Shifters, Logic
Units, ...)
Logic Designer's View
ISA Level
FUs & Interconnect
° Ways in which these components
are interconnected
° Information flows between
components
° Logic and means by which such
information flow is controlled.
° Choreography of FUs to
realize the ISA
° Register Transfer Level (RTL)
Description
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The Big Picture
° Since 1946 all computers have had 5 components
Processor
Input
Control
Memory
Datapath
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Output
©UCB Spring 2003
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Sample Organization: It’s all about communication
Pentium III Chipset
Proc
Caches
Busses
adapters
Memory
Controllers
I/O Devices:
Disks
Displays
Keyboards
Networks
° All have interfaces & organizations
° Um…. It’s the network stupid???!
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What is “Computer Architecture”?
Application
Operating
System
Compiler
Firmware
Instr. Set Proc. I/O system
Instruction Set
Architecture
Datapath & Control
Digital Design
Circuit Design
Layout
° Coordination of many levels of abstraction
° Under a rapidly changing set of forces
° Design, Measurement, and Evaluation
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Forces on Computer Architecture
Technology
Programming
Languages
Applications
Computer
Architecture
Cleverness
Operating
Systems
History
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Technology
DRAM chip capacity
Microprocessor Logic Density
DRAM
Year
Size
1980
64 Kb
1983
100000000
10000000
R10000
Pentium
R4400
256 Kb
i80486
1986
1 Mb
1989
4 Mb
1992
16 Mb
Transistors
1000000
uP-Name
i80286
100000
R3010
i8086
1996
64 Mb
1999
256 Mb
2002
1 Gb
i80386
SU MIPS
i80x86
M68K
10000
MIPS
Alpha
i4004
1000
1965
1970
1975
1980
1985
1990
1995
2000
2005
° In ~1985 the single-chip processor (32-bit) and the
single-board computer emerged
• => workstations, personal computers, multiprocessors have
been riding this wave since
° In the 2002+ timeframe, these may well look like
mainframes compared single-chip computer
CS152 / Kubiatowicz
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©UCB Spring 2003
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Technology => dramatic change
° Processor
• logic capacity: about 30% per year
• clock rate:
about 20% per year
° Memory
• DRAM capacity: about 60% per year (4x every 3 years)
• Memory speed: about 10% per year
• Cost per bit: improves about 25% per year
° Disk
• capacity: about 60% per year
• Total use of data: 100% per 9 months!
° Network Bandwidth
• Bandwidth increasing more than 100% per year!
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Log of Performance
Performance Trends
Supercomputers
Mainframes
Minicomputers
Microprocessors
Year
1970
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1975
1980
1985
©UCB Spring 2003
1990
1995
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Processor Performance (SPEC)
performance now improves ~60% per year (2x every 1.5 years)
300
250
Performance
RISC
200
150
Intel x86
RISC
introduction
100
50
35%/yr
1995
1994
1993
1992
1991
1990
1989
1988
1987
1986
1985
1984
1983
1982
0
Year
Did RISC win the technology battle and lose the market war?
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Applications and Languages
° CAD, CAM, CAE, . . .
° Lotus, DOS, . . .
° Multimedia, . . .
° The Web, . . .
° JAVA, . . .
° The Net => ubiquitous computing
° ???
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Measurement and Evaluation
Design
Architecture is an iterative process
-- searching the space of possible designs
-- at all levels of computer systems
Analysis
Creativity
Cost /
Performance
Analysis
Good Ideas
Bad Ideas
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Mediocre Ideas
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Why do Computer Architecture?
° CHANGE
° It’s exciting!
° It has never been more exciting!
° It impacts every other aspect of electrical
engineering and computer science
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Computers in the News: New IBM Transistor
° Announced 12/10/02
° 6nm gate length!!!
° Details: Still to be announced
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Computers in the news: Tunneling Magnetic Junction
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©UCB Spring 2003
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Computers in the News: Sony Playstation 2000
° (as reported in Microprocessor Report, Vol 13, No. 5)
• Emotion Engine: 6.2 GFLOPS, 75 million polygons per second
• Graphics Synthesizer: 2.4 Billion pixels per second
• Claim: Toy Story realism brought to games!
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Where are we going??
Input
Multiplier
Input
Multiplicand
32
Multiplicand
Register
LoadMp
32=>34
signEx
32
34
34
1
0
34x2 MUX
Arithmetic
Multi x2/x1
34
34
Sub/Add
34-bit ALU
Control
Logic
34
32
32
2
ShiftAll
LO register
(16x2 bits)
Prev
2
Booth
Encoder
HI register
(16x2 bits)
LO[1]
Extra
2 bits
2
"LO
[0]"
Single/multicycle
Datapaths
<<1
32=>34
signEx
ENC[2]
ENC[1]
ENC[0]
LoadLO
ClearHI
LoadHI
2
32
Result[HI]
LO[1:0]
32
Result[LO]
1000
CPU
“Moore’s Law”
IFetchDcd
WB
Exec Mem
Performance
10
DRAM
9%/yr.
DRAM (2X/10 yrs)
1
198
2
3
198
498
1
5
198
6
198
7
198
8
198
9
199
0
199
199
2
199
399
1
4
199
5
199
699
1
7
199
8
199
9
200
0
Exec Mem
Processor-Memory
Performance Gap:
(grows 50% / year)
198
098
1
1
198
IFetchDcd
CS152
Spring ‘99
100
µProc
60%/yr.
(2X/1.5yr)
WB
Time
IFetchDcd
Exec Mem
IFetchDcd
WB
Exec Mem
WB
Pipelining
I/O
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Memory
Systems
©UCB Spring 2003

CS152 / Kubiatowicz
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Maybe even Quantum Computing: Use of “Spin”
North
Representation:
|0> or |1>
Spin ½ particle:
(Proton/Electron)
South
° Particles like Protons have an intrinsic “Spin” when defined
with respect to an external magnetic field
° Kane Proposal: use of impurity Phosphorus in silicon
• Spin of odd proton is used to represent the bit
• Manipulation of this bit via “Hyperfine” interaction with electrons
° Quantum Computers: Factor numbers in Polynomial time!
• Classically this is (sub)exponential problem
• Just cool?
1/22/03
©UCB Spring 2003
CS152 / Kubiatowicz
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CS152: Course Content
Computer Architecture and Engineering
1/22/03
Instruction Set Design
Computer Organization
Interfaces
Hardware Components
Compiler/System View
Logic Designer’s View
“Building Architect”
“Construction Engineer”
©UCB Spring 2003
CS152 / Kubiatowicz
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CS152: So what's in it for me?
° In-depth understanding of the inner-workings of
modern computers, their evolution, and trade-offs
present at the hardware/software boundary.
• Insight into fast/slow operations that are easy/hard to
implementation hardware
• Out of order execution and branch prediction
° Experience with the design process in the context of
a large complex (hardware) design.
• Functional Spec --> Control & Datapath --> Physical implementation
• Modern CAD tools
° Designer's "Conceptual" toolbox.
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Conceptual tool box?
° Evaluation Techniques
° Levels of translation (e.g., Compilation)
° Levels of Interpretation (e.g., Microprogramming)
° Hierarchy (e.g, registers, cache, mem,disk,tape)
° Pipelining and Parallelism
° Static / Dynamic Scheduling
° Indirection and Address Translation
° Synchronous and Asynchronous Control Transfer
° Timing, Clocking, and Latching
° CAD Programs, Hardware Description Languages, Simulation
° Physical Building Blocks (e.g., CLA)
° Understanding Technology Trends
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©UCB Spring 2003
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Course Structure
° Design Intensive Class --- 75 to 150 hours per semester per student
MIPS Instruction Set ---> Standard-Cell implementation
° Modern CAD System (WorkView):
Schematic capture and Simulation
Design Description
Computer-based "breadboard"
• Behavior over time
• Before construction
° Lectures (rough breakdown):
•
•
•
•
•
•
•
•
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Review: 2 weeks on ISA, arithmetic
1 1/2 weeks on technology, HDL, and arithmetic
3 1/2 weeks on standard Proc. Design and pipelining
1 1/2 weeks on advanced pipelining and modern superscalar design
2 weeks on memory and caches
1 1/2 weeks on Memory and I/O
?? Guest lectures/Special lectures (Quantum computing?)
2 weeks exams, presentations
©UCB Spring 2003
CS152 / Kubiatowicz
Lec1.29
Typical Lecture Format
° 20-Minute Lecture
° 5- Minute Administrative Matters
° 25-Minute Lecture
° 5-Minute Break (water, stretch)
° 25-Minute Lecture
° Instructor will come to class early & stay after to
answer questions
Attention
20 min. Break 25 min. Break 25 min. “In Conclusion, ...”
Time
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©UCB Spring 2003
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Course Administration
° Instructor: John Kubiatowicz (kubitron@cs)
673 Soda Hall
Office Hours(Tentative): W 4:00-5:30
° TAs:
TBA
° Labs:
Windows 2000 accounts in 119 Cory
° Materials:
Mirror:
http://inst.eecs.berkeley.edu/~cs152
http://www.cs.berkeley.edu/~kubitron/cs152
° Newsgroup: ucb.class.cs152
° Text: Computer Organization and Design:
The Hardware/Software Interface,
Second Edition, Patterson and Hennessy
• Q: Need 2nd Edition?
yes! >> 50% text changed, all exersizes changed all examples
modernized, new sections, ...
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©UCB Spring 2003
CS152 / Kubiatowicz
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Course Exams
° Reduce the pressure of taking exams
•
•
•
•
Midterms: (approximately) March 5th and May 5th
3 hrs to take 1.5-hr test (5:30-8:30 PM, 277 Cory?).
Our goal: test knowledge vs. speed writing
Review meetings: Sunday before?
• Both mid-terms can bring summary sheets
° Students/Staff meet over pizza after exam at LaVals!
• Allow me to meet you
• I’ll buy!
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©UCB Spring 2003
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Course Workload
° Reasonable workload (if you have good work habits)
• No final exam: Only 2 mid-terms
• Every lab feeds into the project
• Project teams have 4 or 5 members
° Spring 1995 HKN workload survey
(1 to 5, 5 being hardest)
CS 150
CS 152
CS 162
4.2
3.4/3.5
3.9/4.0
CS 164 3.1
CS 169 3.6
CS 184 4.6
° Spring 1997 HKN workload survey
(1 to 5, 5 being hardest)
CS 150
CS 152
CS 162
3.8
3.2
3.3
CS 164 4.0
CS 169 3.2
CS 184 3.3
° Revised Science/Design units: now 3 Science, 2 Design
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©UCB Spring 2003
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Homework Assignments and Project
° Most assignment consists of two parts
• Individual Effort: Exercises from the text book
• Team Effort: Lab assignments
• First Homework: out later today on Website.
° Assignments (usually) go out on Wednesday
• Exercises due on a later Wednesday at beginning of lecture
- Brief (15 minute) quiz on assignment material in lecture
- Must understand assignment to do quiz
- No late assignments!
• Labs reports due by midnight via submit program on Thursday.
° Lab Homeworks returned in discussion section
• To spread computer workload
• put section time on them homeworks
° Discussion sections start next week
• 101
Th 10:00 – 2:00 in 310 Hearst Mining
• 102
Th 4:00 – 6:00 in 3 Evans
• Must turn in survey to be considered enrolled (online tomorrow)
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My Goal
° Show you how to understand modern computer
architecture in its rapidly changing form.
° Show you how to design by leading you through
the process on challenging design problems
° Learn how to test things.
° NOT to talk at you
° so...
•
•
•
•
1/22/03
ask questions
come to office hours
find me in the lab
...
©UCB Spring 2003
CS152 / Kubiatowicz
Lec1.35
Project/Lab Summary
° Tool Flow runs on many workstations in Cory, but
119 Cory is primary CS152 lab.
° Get instructional UNIX account now (“name account”)
° Get card-key access to Cory now (3rd floor...)
° Lab assignments:
•
•
•
•
•
•
•
Lab 1 Nothing to do! (1 week )
Lab 2 C -> MIPS, SPIM (2 weeks)
Lab 3 Fast ALU Design (2 week) + Intro to hardware synthesis
Lab 4 Single Cycle Processor Design (2 weeks)
Lab 5 Pipelined Processor Design (2 weeks)
Lab 6 Cache & DMA Design (3 weeks)
Lab 7 Open ended work for final project
° 2-hour discussion section for later in term. Early
sections may end in 1 hour. Make sure that you are free
for both hours however!
° team in same section!
° Oral presentation and written report
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©UCB Spring 2003
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Grading
° Grade breakdown
•
•
•
•
•
•
Two Midterm Exams:
Labs and Design Project:
Homework Completion:
Quizzes:
Project Group Participation
Class Participation:
35% (combined)
35%
5%
15%
5%
5%
° No late homeworks or labs:
our goal grade, return in 1 week
° Grades posted on home page/glookup?
• Don’t forget secret code on survey
• Written/email request for changes to grades
° CS Division guideline upper division class GPA
between 2.7 and 3.1.
• average 152 grade will be a B or B+; set expectations accordingly
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©UCB Spring 2003
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Course Problems
° Can’t make midterm
• Tell early us and we will schedule alternate time
° Forgot to turn in homework/ Dog ate computer
• NO late homeworks or labs.
° What is cheating?
• Studying together in groups is encouraged
• Work must be your own
• Common examples of cheating: running out of time on a
assignment and then pick up output, take homework from box and
copy, person asks to borrow solution “just to take a look”, copying
an exam question, ...
• Better off to skip assignment (homeworks: 5% of grade!)
• Labs worth more. However, each lab worth ~5% of grade.
• Doesn’t help on quiz (15%of grade) anyway
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Class decides on penalties for cheating; staff enforces
° Exercises (book):
• 0 for problem
• 0 for homework assignment
• subtract full value for assignment
• subtract 2X full value for assignment
° Labs leading to project (groups: only penalize
individuals?)
•
•
•
•
0 for problem
0 for laboratory assignment
subtract full value of laboratory
subtract 2X full value of laboratory
° Exams
• 0 for problem
• 0 for exam
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©UCB Spring 2003
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Project Simulates Industrial Environment
° Project teams have 4 or 5 members in same
discussion section
• Must work in groups in “the real world”
° Communicate with colleagues (team members)
• Communication problems are natural
• What have you done?
• What answers you need from others?
• You must document your work!!!
• Everyone must keep an on-line notebook
° Communicate with supervisor (TAs)
• How is the team’s plan?
• Short progress reports are required:
- What is the team’s game plan?
- What is each member’s responsibility?
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©UCB Spring 2003
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Things We Hope You Will Learn from 152
° Keep it simple and make it work
• Fully test everything individually and then together
• Retest everything whenever you make any changes
• Last minute changes are big “no nos”
° Group dynamics. Communication is the key to
success:
• Be open with others of your expectations and your problems
• Everybody should be there on design meetings when key decisions
are made and jobs are assigned
° Planning is very important:
• Promise what you can deliver; deliver more than you promise
• Murphy’s Law: things DO break at the last minute
- Don’t make your plan based on the best case scenarios
- Freeze you design and don’t make last minute changes
° Never give up! It is not over until you give up.
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©UCB Spring 2003
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What you should know from 61C, 150
° Basic machine structure
• processor, memory, I/O
° Read and write basic C programs
° Read and write in an assembly language
• MIPS preferred
° Understand the steps in a make file and what they
do
• compile, link, load & execute
° Understand the concept of virtual memory
° Logic design
• logical equations, schematic diagrams, FSMs, components
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©UCB Spring 2003
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Getting into CS 152
° If not preenrolled, Fill out petition form
° Fill out survey and return Monday in class
° Know the prerequisites
• CS 61C - assembly language and simple computer organization
• CS 150 - Logic design. This prerequisite is changing. Still expect some
knowledge of logic design and state machine design.
° Prerequisite quiz on Monday 2/3; Pass/Fail
•
•
•
•
UC doesn’t always enforce prerequisites
TA’s will hold review sessions in section next Thursday+1 other time
Need to pass prerequisite quiz to take CS 152
Previous preq quizzes on web pages.
• New material: something about single-cycle processor design….
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©UCB Spring 2003
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Levels of Representation (61C Review)
temp = v[k];
High Level Language
Program
v[k] = v[k+1];
v[k+1] = temp;
Compiler
lw$15,
lw$16,
sw
sw
Assembly Language
Program
Assembler
Machine Language
Program
0000
1010
1100
0101
1001
1111
0110
1000
1100
0101
1010
0000
0110
1000
1111
1001
0($2)
4($2)
$16, 0($2)
$15, 4($2)
1010
0000
0101
1100
1111
1001
1000
0110
0101
1100
0000
1010
1000
0110
1001
1111
Machine Interpretation
Control Signal
Specification
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°
°
ALUOP[0:3] <= InstReg[9:11] & MASK
©UCB Spring 2003
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Levels of Organization
SPARCstation 20
Computer
Workstation Design Target:
25% of cost on Processor
25% of cost on Memory
(minimum memory size)
Rest on I/O devices,
power supplies, box
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Processor
Memory
Devices
Control
Input
Datapath
Output
©UCB Spring 2003
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Execution Cycle
Instruction
Obtain instruction from program storage
Fetch
Instruction
Determine required actions and instruction size
Decode
Operand
Locate and obtain operand data
Fetch
Execute
Result
Compute result value or status
Deposit results in storage for later use
Store
Next
Instruction
1/22/03
Determine successor instruction
©UCB Spring 2003
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Lec1.46
The SPARCstation 20
SPARCstation 20
Memory SIMMs
Memory
Controller
SIMM Bus
MBus
MBu
s
MBu
s
Slot 1
Slot 0
MSBI
1/22/03
Disk
SBus
Slot 1
SBus
Slot 3
SBus
Slot 0
SBus
Slot 2
SEC
MACIO
SBus
Keyboard
Floppy
& Mouse
Disk
©UCB Spring 2003
Tape
SCSI
Bus
External Bus
CS152 / Kubiatowicz
Lec1.47
The Underlying Interconnect
SPARCstation 20
SIMM Bus
Memory
Controller
Standard I/O Bus:
SCSI Bus
Processor/Mem Bus:
MBus
Sun’s High Speed I/O Bus:
SBus
MSBI
SEC
MACIO
Low Speed I/O Bus:
External Bus
1/22/03
©UCB Spring 2003
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Lec1.48
Processor and Caches
SPARCstation 20
MBus
Module
Processor
MBus
MBu
s
MBu
s
Slot 1
Registers
Datapath
Internal
Cache
Control
Slot 0
External Cache
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Memory
SIMM Slot 7
SIMM Slot 6
SIMM Slot 5
SIMM Slot 4
SIMM Slot 3
SIMM Slot 2
SIMM Slot 1
Memory
Controller
SIMM Slot 0
SPARCstation 20
Memory SIMM Bus
DRAM SIMM
1/22/03
DRAM
DRAM
DRAM
DRAM
DRAM
DRAM
DRAM
DRAM
DRAM
DRAM
©UCB Spring 2003
CS152 / Kubiatowicz
Lec1.50
Input and Output (I/O) Devices
SPARCstation 20
° SCSI Bus: Standard I/O
Devices
° SBus: High Speed I/O
Devices
° External Bus: Low Speed I/O
Device
Disk
SBus
Slot 1
SBus
Slot 3
SBus
Slot 0
SBus
Slot 2
Tape
SBus
SEC
1/22/03
MACIO
Keyboard
Floppy
& Mouse
Disk
©UCB Spring 2003
SCSI
Bus
External Bus
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Lec1.51
Standard I/O Devices
SPARCstation 20
° SCSI = Small Computer Systems Interface
° A standard interface (IBM, Apple, HP, Sun
... etc.)
° Computers and I/O devices communicate
with each other
° The hard disk is one I/O device resides on
the SCSI Bus
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Disk
Tape
SCSI
Bus
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High Speed I/O Devices
SPARCstation 20
° SBus is SUN’s own high speed I/O bus
° SS20 has four SBus slots where we can plug
in I/O devices
° Example: graphics accelerator, video adaptor,
... etc.
° High speed and low speed are relative terms
SBus
Slot 1
SBus
Slot 3
SBus
Slot 0
SBus
Slot 2
SBus
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Slow Speed I/O Devices
SPARCstation 20
° The are only four SBus slots in SS20--”seats”
are expensive
° The speed of some I/O devices is limited by
human reaction time--very very slow by
computer standard
° Examples: Keyboard and mouse
° No reason to use up one of the expensive
SBus slot
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Keyboard
Floppy
& Mouse
Disk
©UCB Spring 2003
External Bus
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Summary: It’s all about communication
Pentium III Chipset
Proc
Caches
Busses
adapters
Memory
Controllers
I/O Devices:
Disks
Displays
Keyboards
Networks
° All have interfaces & organizations
° Um…. It’s the network stupid???!
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Summary
° All computers consist of five components
• Processor: (1) datapath and (2) control
• (3) Memory
• (4) Input devices and (5) Output devices
° Not all “memory” are created equally
• Cache: fast (expensive) memory are placed closer to the
processor
• Main memory: less expensive memory--we can have more
° Interfaces are where the problems are - between
functional units and between the computer and the
outside world
° Need to design against constraints of performance,
power, area and cost
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©UCB Spring 2003
CS152 / Kubiatowicz
Lec1.56