중간 고사 review (part 1: high-level...

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중간 고사 review (Part 1: high-level overview)

Bryan S. Kim

Before we get started…

• Office hour change for this week

– 4/11 (Thurs.) instead of 4/12 (Fri.)

– 301-517, 16:30-17:30

• Midterm review (part 2, with exercises)

– 4/15 (Mon.), in class

– Both English and Korean will be used

Before we get started…

• Office hour change for this week

– 4/11 (Thurs.) instead of 4/12 (Fri.)

– 301-517, 16:30-17:30

• Midterm review (part 2, with exercises)

– 4/15 (Mon.), in class

– Both English and Korean will be used

Before we get started…

• Office hour change for this week

• Midterm review (part 2, with exercises)

• Midterm on 4/17 (Wed.)

– Closed-book, closed-notes

– Bring your ID

– Only your writing utensils will be allowed on your desk

– All exam questions will be variations of the textbook exercises

The entire course in a nutshell

• The underlying structure of a computer

– Chap 1~Chap 10

• Programming in a high-level language

– Chap 11~Chap 19

My interpretation of the textbook

A computing system &

data representation

Chap 1~2

My interpretation of the textbook

A computing system &

data representation

Digital logic

Von Neumann machine

LC-3 ISA

Assembly language

Service routines & subroutines

Doing cool stuff with assembly

… want to do cooler stuff

Chap 1~2

Chap 3~10

My interpretation of the textbook

A computing system &

data representation

Digital logic

Von Neumann machine

LC-3 ISA

Assembly language

Service routines & subroutines

Doing cool stuff with assembly

C language

Functions

Doing cooler stuff with C

… want to do cooler stuff

Chap 1~2

Chap 3~10

Chap 11~19

What this course touches upon

from cse.snu.ac.kr

Important ideas from Chap. 1

• Abstraction

– What does it hide?

– What does it expose?

– Interface and implementation

Important ideas from Chap. 1

• Abstraction

• Hardware vs. software

– How machines are built and programmed

– How programs are built on top of machines

Important ideas from Chap. 1

• Abstraction

• Hardware vs. software

• Universal computing device

– Big or small, capabilities are the same

• Efficiency, that’s another story

– The reason why we are studying LC-3

Important ideas from Chap 2.

• Integer representation

– Sign-magnitude

– 1’s complement

– 2’s complement

Important ideas from Chap 2.

• Integer representation

• Operations

– Arithmetic

• Add, subtract, sign-extension, overflow

– Logical

• AND, OR, NOT, NAND, NOR

Important ideas from Chap 2.

• Integer representation

• Operations

• Other data types

– Floating point

– ASCII

Important ideas from Chap 3.

• Transistors and logic gates

– NMOS, PMOS, CMOS

– NOT, NAND, NOR

– Truth table circuit (logical completeness)

– DeMorgan’s Law and other properties

Important ideas from Chap 3.

• Transistors and logic gates

• Combinational logic

– Decoder

• n-bit to 2n-bit

– Mux

• Selects one to output among 2n inputs

– Adder

• 1-bit adder ripple-carry adder

Important ideas from Chap 3.

• Transistors and logic gates

• Combinational logic

• Storage elements

– Latch gated latch register

– Memory

• A simplified (?) representation of what it could look like

Important ideas from Chap 3.

• Transistors and logic gates

• Combinational logic

• Storage elements

• Sequential logic

– Flip-flop

• Like latch, but “holds” data

– Finite state machine

• Circuit State transition diagram

Latches, FFs, and registers are sometimes intermixed in literature, but we’ll go with the definition in the text.

Important ideas from Chap 4.

• Von Neumann model

– Memory: MAR, MDR

– Processing unit: ALU, TEMP

– Control unit: PC, IR

– Input

– Output

Important ideas from Chap 4.

• Von Neumann model

• Instruction processing

– Instruction fetch

– Instruction decode

– Evaluate address

– Fetch operands

– Execute

– Store result

Important ideas from Chap. 5

• LC-3 ISA

– What does an ISA expose?

• Memory, registers, instructions

– LC-3 instruction format

Important ideas from Chap. 5

• LC-3 ISA

• LC-3 instruction types – Operate

• Register-to-register

• Register vs. immediate mode

– Data movement • Register-to/from-memory

• PC-relative vs. Base-offset vs. Indirect

– Control: PC change • Condition code

Important ideas from Chap. 5

• LC-3 ISA

• LC-3 instruction types

• Details in LC-3 ISA

– What goes on for each instruction for each instruction processing phase

Important ideas from Chap 6.

• Problem solving

– Step-wise refinement

– Constructs

• Sequential

• Conditional

• Iterative

Important ideas from Chap 6.

• Problem solving

• Debugging

– What a debugger should provide

– How to debug

• Step, breakpoint, watchpoint

– Types of mistakes

• Syntax, logic, data

Important ideas from Chap 7.

• Assembly language syntax

– Instruction

– Label

– Comment

– Pseudo-op

Important ideas from Chap 7.

• Assembly language syntax

• Assembly process

– Two-pass process

• Symbol table

• Location count

Important ideas from Chap 8.

• I/O (device) CPU

– Device register

– Memory-mapped vs. special instructions

– Sync vs. async

– Polling vs. interrupt

Important ideas from Chap 8.

• I/O (device) CPU

• LC-3 computer’s keyboard & monitor I/O

– Memory-mapped, asynchronous, polling

– Hardware-software synchronization

• What the device hardware does

• What the software should do

Only polling is covered in this chapter.

Important ideas from Chap 9.

• System call mechanism

– System control block

– What happens on TRAP?

– What happens on RET (JMP R7)?

Important ideas from Chap 9.

• System call mechanism

• Subroutine

– What happens on JSR/R?

– How do we pass arguments and get return values from subroutines?

Important ideas from Chap 10.

• Stack

– What it is, how it works, how to implement.

Important ideas from Chap 10.

• Stack

• Interrupt handling

– Processor state

• Particularly, Processor Status Register (PSR), Saved.SSP and Saved.USP

– What happens on jumping into interrupt service routine (ISR)

– What happens on return from interrupt (RTI)

What the ISR exactly does isn’t extensively covered in text. How to decide between polling and interrupt isn’t covered in detail, either.

Why are we learning hardware?

Why are we learning hardware?

J. H. Hennessy and D. A. Patterson, “A New Golden Age for Computer Architecture” in CACM 2019