unit 1 introduction Flashcards
what is architecture?
the design of the system visible to the assembly-level programmer. ( what instructions, how many registers, memory addressing scheme)
What is organization?
how the architecture is implemented.
what does the Central Processing Unit(CPU) contain?
The control logic and the Arithmetic Logic Unit (ALU), registers, and program counter register
what does the control logic do?
it initiates most activities on the computer
What does the Arithmetic Logic Units(ALU) do?
performs the math and logic calculations for the CPU.
what does a register contain?
temporary data values
what does the program counter register contain?
the address of the next instruction to execute
what is the bus?
a set of parallel wires that connect the CPU, memory, and I/O controllers
what does a bus’s chipset do?
it determines who can use the bus at any given instant
what does the width of the bus determine?
the maximum memory configuration
What does I/O stand for?
input/output
what does the I/O controller do?
direct the flow of data to and from I/O devices.
how does the I/O controller know to initiate I/O?
The CPU sends a request
What is the internal memory called?
Random Access Memory (RAM)
What is kept in the RAM?
data and program instructions
what is the order of the memory hierarchy from bottom to top?
removable media, DISK, RAM, cache, regs
what does the instruction cycle do?
fetch instructions from memory and execute the instruction
where does the the instruction cycle fetch instructions?
from the memory address in the Program Counter register
what does the instruction cycle increment?
the Program counter
what does the instruction cycle decode?
the type of instruction
the instruction cycle fetches ___ and stores___
operands, results
in the simple model of execution, an instruction sequence is determined by?
a simple conceptual control point
in the simple model of execution, how are instructions completed?
One instruction is executed at a time. Each instruction is completed before the next instruction starts
what are the layers in which you can consider computer operations?
Applications, middleware, High level languages, machine language, microcode, logic circuits, gates, transistors, silicon structures
what are the different meanings of the binary values?
1 can be TRUE or HIGH and ) can be FALSE or LOW
how do digital circuits represent 1 and 0?
they use voltage levels
what system operates on a fixed number of bits?
Digital systems
what is overflow?
when a result is too big to fit in the available number of bits
what are instructions?
commands in a computer’s language
instruction languages are?
Assembly languages: human-readable format
machine language: computer-readable format(1’s and 0’s)
Architecture design principles
1) regularity supports design simplicity
2) make the common case fast
3) smaller is faster
4) good design demands good compromises
what does regularity supports design simplicity mean?
consistent instruction format
the same number of operands should be used
there should be ease when encoding and handling hardware
what is hierarchy?
dividing a system into modules, then further subdividing each of these modules until the pieces are easy to understand.
modularity states?
the modules have well-defined functions and interfaces, so they connect together easily without unanticipated side effects.
Regularity seeks?
uniformity among modules. Common modules are reused many times, reducing the number of distinct modules needing to be designed
Regularity teaches?
that interchangeable parts are a good idea
what does the amount of information D represent?
refers to a discrete-valued variable with N distinct states. Measured in units of bits
what does an N-digit decimal number represent?
one of 10^N possibilities: 0,1,2,3,…,10^N -1
what are Bits represented by?
0 or 1
what are binary numbers?
0’s or 1’s joined together
how much weight does each binary column have?
twice the amount of the previous column
what is base 16?
hexadecimal
what are hexadecimal numbers?
0 to 9 along with letters A to F
what are the weights of the columns in base 16?
1,16,16^2(256), 16^3(4096)
how do you convert hexadecimal to binary?
each hexadecimal digit directly corresponds to four binary digits
what is the hex digit A equal to?
10, 1010
what is the hex digit B equal to?
11, 1011
what is the hex digit C equal to?
12, 1100
what is the hex digit D equal to?
13, 1101
what is the hex digit E equal to?
14, 1110
what is the hex digit F equal to?
15, 1111
how do you convert 2ED Hex to decimal
2 x16^2 + Ex16^1 + D x 16^0 = 749(10)
what is a group of eight bits called?
a byte, which represents one of 2^8 possibilities
what is a group of 4 bits called?
a nibble or half a byte. represented by one of 2^4 possibilities
microprocessors handle data in chunks also called?
words
64-bit processors operate on?
64-bit words
what is the least significant bit(lsb)?
groups of bits in the 1’s column
