Day 3

Question 1

Order of Magnitude

Answer 1

comes from the scientific notation of very large numbers in which each order of magnitude is ten times the previous one. (computers use an abridged version to describe how big or fast something is)

Question 2

Exa 
Peta
Tera
Giga
Mega
Kilo

Milli
Micro (u)
Nano

Answer 2

10^18 --> 2^60 
10^15 --> 2^50
10^12 --> 2^40
10^9 --> 2^30
10^6 --> 2^20
10^3 --> 2^10

10^-3
10^-6
10^-9

Question 3

Digital Logic

Answer 3

use of electronic switches to solve Boolean functions.

Question 4

Closed vs Open with circuits

Answer 4

Closed = on = T
Open = off = F

Question 5

Logic Gates

Answer 5

electronic device that performs Boolean operations

Question 6

What is an I/O table

Answer 6

lists all possible input signals together with their corresponding output signals

Question 7

Know what the symbols for:

Answer 7

AND
OR
NOT
NAND
NOR
XOR
look like

Question 8

What is current computer architecture derived from ?

Answer 8

John Von Neumann’s 1945 draft report on the electronic discrete variable automatic computer (EDVAC)

Question 9

What is a stored-program concept?

Answer 9

allows instructions and data to be stored in memory rather than being manually entered every time the program is run.

Question 10

The Harvard Architecture

Answer 10

solves bottleneck by having separate memory and I/O for data read, data write, and instruction read. Allows the writing of data to memory while the next instruction is being read.

Question 11

CPU

Answer 11

Central processing unit aka processor.
Active part of the computer.
Contains data paths and controls

Question 12

Memory

Answer 12

storage area where programs are kept when they are running.

Question 13

I/O

Answer 13

How we pass data between the CPU and memory.
input = keyboard, mouse
output = monitor printer

Question 14

Little man Computer

Answer 14

created by Stuart Madnick. introduces simplified, but typical set of instructions a computer can perform.

Question 15

Registers

Answer 15

small amounts of storage space within the CPU used to perform operations. There are two types GPR (any purpose) and SPR (single/special purpose)

Question 16

Accumulator

Answer 16

A - 3 digit GPR used by the arithmetic logic unit. executes arithmetic ops and logic decisions.

Question 17

Program counter (PC)

Answer 17

2 digit SPR used to point the CU to the correct memory address of the next instruction

Question 18

Instruction register (IR)

Answer 18

3 digit SPR used by the decoder to decode the instruction.

Question 19

Memory Address Register (MAR)

Answer 19

2 digit SPR used to point to the correct memory address to read or write.

Question 20

Memory Data Register (MDR)

Answer 20

3 digit SPR used to hold data to be read from or written to the ALU or memory. there are 100 memory addresses 0-99; each can hold 3 digits.

Question 21

Memory Management Unit (MMU)

Answer 21

manages data passed to or fetched from memory.

Question 22

Control Unit (CU)

Answer 22

performs fetch and decode steps by moving data and addressses between the registers and I/O or MMU

Question 23

Instruction Set Architecture (ISA)

Answer 23

vocabulary of commands understood by the CPU and the interface that allows all software to run on the hardware.

Question 24

Opcode

Answer 24

numeric value that represents an instruction to the CPU

Question 25

Mnemonic

Answer 25

(short character sequence) represents each opcode

Question 26

Operand

Answer 26

indicates what data the opcode is to work with

Question 27

Fetch-decode-execute (F-D-E) cycle

Answer 27

process used by the CPU to retrieve, interpret, and perform each instruction of a program.

Question 28

Machine control

Answer 28

HLT 000
PC –> MAR
MDR –> IR

Question 29

Arithmetic (ADD)

Answer 29

ADD 1XX
PC --> MAR
MDR --> IR
IR (ADDR) --> MAR
A + MDR --> A
PC + 1 --> PC

Question 30

Arithmetic (SUB)

Answer 30

SUB 2XX
PC --> MAR
MDR --> IR
IR (ADDR) --> MAR
A - MDR --> A
PC + 1 --> PC

Question 31

Data Transfer (STA)

Answer 31

STA 3XX 
PC --> MAR
MDR --> IR
IR (ADDR) --> MAR
A --> MDR (INTO MEMORY)
PC + 1 --> PC

Question 32

Data Transfer (LDA)

Answer 32

LDA 5XX
PC --> MAR
MDR --> IR
IR (ADDR) --> MAR
MDR --> A (OUT OF MEMORY)
PC + 1 --> PC

Question 33

Control Transfer (BRA)

Answer 33

BRA 6XX
PC –> MAR
MDR –> IR
IR (ADDR) –> PC

Question 34

Control Transfer (BRZ)

Answer 34

BRZ 7XX
PC --> MAR
MDR -->IR
IF A = = 0 THEN
  IR (ADDR) --> PC
ELSE 
PC + 1 --> PC

Question 35

Control Transfer (BRP)

Answer 35

BRP 8XX
PC --> MAR
MDR --> IR
IF A >= 0 THEN
   IR (ADDR) --> PC
ELSE 
  PC + 1 --> PC

Question 36

I/O (INP)

Answer 36

INP 901 
PC --> MAR
MDR --> IR
INBOX --> A
PC + 1 --> PC

Question 37

I/O (OUT)

Answer 37

OUT 902
PC --> MAR
MDR --> IR
A --> OUTBOX
PC + 1 --> PC