8 - Architecture & Assembly Language Flashcards
(26 cards)
What is a word in the context of a 32-bit machine?
Group/number of bits which can be addressed/transferred/manipulated as a single unit/in one go/at a time
Define the term instruction set.
The set/list of bit patterns/binary codes representing machine operations; the set/list of bit patterns/binary codes for which machine operations have been defined
What is meant by the stored program concept?
Program stored in main memory; instructions fetched and executed by processor; program can be replaced by loading another program into (main) memory
What connects the processor and main memory?
(Data/address/control/internal/system) bus
What is the purpose of secondary storage?
Store programs and/or data/files when not in use; when computer is off permanent/long term storage of programs and/or data; save programs/data
Describe the role of an I/O controller.
Allows processor to control/communicate with a peripheral using an (I/O) port; translates signals/data received from a peripheral into a form that can be processed by the computer; allows new peripherals to be added without redesigning the processor/computer hardware; allows peripheral designers to create new peripherals to one common interface standard
State an example of how the control bus is used when the processor stores data into main memory.
Indicate that a memory write is occurring; transfer clock signal; indicate the number of bits being transferred; receive transfer acknowledgement; send signal to request use of (system) bus
Describe two advantages of using the Harvard architecture compared to the von Neumann architecture.
- Avoid/reduce bottleneck of single data/address bus(es)
- Avoids possibility of data being executed as code
What are some ways hardware performance could be improved in Servers/PCs?
- Replace the processor with one which has more cores
- Install more RAM
- Use SSDs instead of HDDs
- Replace the motherboard with one which has buses that run at a faster clock speed
What is the consequence of increasing the width of the data bus?
Increase the number of bits that can be transferred at one time
What is the consequence of increasing the width of the address bus?
Increases the number of (memory) addresses/addressable locations
What is the consequence of increasing the clock speed?
Instructions performed more quickly; fetch execute cycle will happen faster
Describe a part of the I/O controller.
Electronics that interface the controller to the system bus; electronics appropriate for sending signals to the device connected to the computer
What is a Bus?
A set of/group of/parallel wires/lines
Give two examples of a signal carried by the control bus.
- Clock/timing
- Reset
Give one use of ROM inside a computer.
Bootstrap Program
Give three uses of RAM inside a computer.
- User Data
- Application Software
- System Software
Describe what an interrupt is and explain the purpose of interrupts.
A signal/request sent to the processor; so that a device/source that needs immediate attention of the processor can be serviced
Describe the role of the control unit.
To marshal/control operation of fetch-execute cycle; controls fetching/loading/storing operations; to execute some instructions
Explain why the volatile environment must be saved before an interrupt is serviced.
So that the currently running process/task/program can be returned to; as the code that deals with the interrupt will change/overwrite register values
Explain the difference between direct addressing and immediate addressing.
Direct addressing means that the operand is the memory address; immediate addressing means the operand is the datum
State the full names of two special purpose registers used in the fetch part of the fetch-execute cycle.
- Program Counter
- Memory Address Register
What does an opcode represent?
Indicates the basic machine operation/function/command
What does an operand represent?
Represents a single item of (binary) data/a single value
