Unit 4 : CPU and Memory Flashcards
List out the major components of CPU ( 2 )
- ALU ( Arithmetic Logic Unit )
- CU ( Control Unit )
What are the subcomponents in CPU? ( 2 )
- Memory Management Unit
- I/O Interface
- Memory Management Unit - supervises instructions and data from memory
- I/O Interface - Sometimes combined with memory management unit as Bus Interface Unit
What is the usage in ALU ?
- Performs calculations and comparisons
- Logical Operation
- Math Calculation
What is the usage in CU? ( 2 )
- Access program instructions and issues commands to the ALU
- Moves data to and from CPU registers and other hardware components
- Contols the movement of data in/out of the CPU
- Controls all other component of the CPU
What is registers?
- It is a small,permanent storage locations within the CPU used for a particular purpose
What unit controls registers directly ?
- Control Unit
What are the digits registers stores
- Bits or Bytes
What are the part for fetching and decoding
- CU
What are the part for executing?
- ALU
What are the part for storing?
- Registers
- Registers are like pockets in our shirts where we store things for disposal
List out the type of registers ( 2 )
- General Purpose Registers
- Special-Purpose Registers
List out all the special-purpose registers ( 5 )
- Program Count Register ( PC )
- Instruction Register ( IR )
- Memory Address Register ( MAR )
- Memory Data Register ( MDR )
- Status Registers
What is also called Instruction Pointer?
- Program Count Register
What stores instruction fetched from memory?
- Instruction Register
What stores the address of what is to be fetched by the CPU?
- Memory Address Register ( MAR )
What stores the data that is fetched?
- Memory Data Registers ( MDR )
What stores the current content of the CPU?
- Status Registers
List out the operations of register ( 4 )
- Sotres values from other locations ( regisers and memory )
- Addition and subtraction
- Shift or rotate data
- Test contents for condtition such as zero or positive
What are the usage of registers?
- Scratchpad for currently executing program
- Holds data needed quickly or frequently
- Stores information about status of CPU and currently executing program
- Address of next program instruction
- Signals from external devices
Is it correct that each memory location has a unique address?
- Yes
Which is a two way register?
- Memory Data Register ( MDR )
What is the transfer take place?
- Between MDR and Memory
What is the 2 factors for determine memory capacity?
- Number of bits in the MAR
- Size of the address portion of the instruction
- 4 bits allows 16 locations
- 8 bits allows 256 locations
- 32 bits allows 4,292,967,296 or 4 GB
List out the types of RAM ( 2 )
- DRAM ( Dynamic RAM )
- SRAM ( Static RAM )
What RAM is the most common, cheap,less electtical power, less heat, smaller space?
- DRAM
What is the tem Volatile
- Must be refreshed ( recharged with power ) 1000 times each second
Which RAM is faster and more expensive?
- SRAM
What are the usage of SRAM?
- Cache Memory
What is stored inside ROM ( Read-Only Memory )
- Holds software that is not expected to change over the life of the system
What is the full name of EEPROM?
- Electrically Erasable Programmable ROM
Which memory is faster than disk but more expensive, users hot carrier injection to store bits of data, slow rewrite time compared to RAM and useful for nonvolatile portable computer storage?
- Flash Memory
List out the 4 kinds of signals
- Data
- Addressing
- Control Signals
- Power ( Sometimes )
What is a bus?
- A physical connection that makes it possible to transfer data from one location in the computer system to another
- Group of electrical or optical conductors for carrying signals from one location to another
What are the characteristics of bus ? ( 10 )
- Number of separate conductors
- Data width in bits carried simultaneously
- Addressing capacity
- Lines on the bus are for a single type of signal or shared
- Throughput - data transfer rate in bits per second
- Distance between 2 endpoints
- Number and type of attachments supported
- Type of control required
- Definied purpose
- Features and capabilities
How does bus categorizate? ( 3 )
- Parallel vs Serial Bus
- Direction of Transmission
- Method of Interconnection
List out the 3 direction of transmission for bus
- Simplex
- Undirectional
- Half Duplex
- Bidirectional, One direction at a time
- Full Duplex
- Bidirectional simultaneously
List out the 2 method of interconnection
- Point-to-point
- Single source to single destination
- Multipoint bus
- Also broadcast bus or multidrop bus
- Connect multiple points to one another
- Cables - Point-to-point buses that connect to an external device
How many bits transmitted at a time when bus interface uses serial method?
- 1 but at a time
What is serial method at bus interface ?
- Single data line pair and a few control lines
How many bits transmitted at a time when bus interface uses parallel method?
- High throughput because all bits of a word are transmitted simultaneously
Which buses ( parallel , serial ) is expensive and require a lot of space?
- Parallel Buses
Which buses ( parallel , serial ) is generally used for short distances ( CPU buses and Computer Motherboards ) ?
- Parallel
- Subject to radio generated electrical interface which limits their speed and length
List out all the classification of instructions ( 8 )
- Data Movement ( Load, Store )
- Arithmetic
- Boolean Logic
- Single Operand Manipultion Instructions
- Bit Manipulation Instructions
- Shift and Rotate
- Stack Instructions
- I/O and Machine Control
Which classification of instructions involve most common, greatest flexibility?
- Data Movement ( Load, Store )
- It also the most common and provide greatest flexibility
What classification of instructions uses operator ( + - * / ) , integers and floating point?
- Arithmetic
Which classification of instructions often includes at least AND, XOR and NOT?
- Boolean Logic
Which classifications of instructions provides negating, decrementing, incrementing, set to 0 ?
- Single Operand Manipulation Instructions
Which classifications of instructions flags to test for conditions?
- Bit Manipulation Instructions
What classifications of instructions does jump and branch, subroutine call and return?
- Program Control
What classigfications of instructions does LIFO method for organizing information and items removed in the reverse order from that in which they are added?
- Stack Instructions
What does PUSH do?
- Increments pointer, then stores data
What does POP do?
- loads data, then decrements pointer
What does Multiple Data Instructions mean?
- Perform a single operation on multiple pieces of data simultaneously
What does Multiple Data Instruction commonly used in?
- Multimedia, vector and array processing applications
What does SIMD mean?
- Single Instruction, Multiple Data
