TAK Flashcards
Computer techniques and architecture
before the advent of universal, electronic digital machines
Generation O
computers built based on vacuum tubes
Generation 1
computers built based on transistors
Generation 2
computers built based on small or medium-scale TTL integrated circuits
Generation 3
computers built based on high-scale integration of microprocessors
Generation 4
computers built based on unconventional solutions
Generation 5
it’s a law formulated in 1965 by Gordon Moore, which in its original form says thet the number of transistors in an electrical system doubles every year (in 1999, doubling would occur every 4-5 years).
Moore’s Law
erasing one bit of information in an environment with temperature T requires a loss (dissipation) of energy (or heat release) of at least kT ln2, where k is the Boltzmann constant. (increasing density and clock frequency more heat)
Landauer’s principle
The average distance of silicon atoms is
0.25 nm (density 5*10^22 /cm^3)
For lithography ____ number of atoms along the side of the gate = 10.000
2.7 um (0,0027 mm/ u-micro)
Dielectric strength of silicon dioxide
5 MV/cm
Programs that use the functions of the operating system to solve problems
Software
It supports computer hardware, manages system resources and provides API and drivers for application software
Operating system
Describes an electronic circuit from a programmer’s perspective.
Defines a set of instructions, and visible registers.
Architecture
Data buses, controllers
Microarchitecture
It combines digital circuits to create functional blocks such as adders, multiplexers, etc.
Logical level
Uses analog circuits to create models of digital circuits (AND gates,
NOT, etc.)
Digital circuit level
Combines components into circuits with the desired properties (filters, amplifiers)
Analog circuit level
Uses components such as transistors and diodes
Electronic level|
Explores the world and systematizes the acquired knowledge into laws and theories that can be relatively easily studied by other people
Physics
how everything is organized, how elements are connected and how it works together. (Exo-, Endo-)
Architecture
- SISD (single instruction, single data)
- SIMD (single instruction, multiple data)
- MISD (multiple instructions, single data)
- MIMD (multiple instruction, multiple data)
Computer architecture can be classified, for example, according to the type of processor-memory connections and the way they are used:
- CISC Architecture (complex instruction set computer)
- RISC Architecture (reduced instruction set computer)
- CCR Architecture (CISC-core-RISC: RISC as a core, but from outside this processor looks like CISC)
Computer architecture can also be classified, e.g. due to the list of instructions:
slow, complicated, but good for programmers because of instructions.
CISC
fast, but reduced amount of instructions.
RISC
a little bit slower that RISC, but fast, and has instructions like CISC.
CCR
- Only one bus to connect a single memory with processor
- Common memory for both data and program code
- Allows you to auto-modify the program
Von Neumann Architecture
- Separate program and data memory
- Faster, but problematic data flow from a program memory to the operating memory area
Harvard Architecture
- One memory card, but inside it is divided into memory for
data and for application - Two buses, data can be modified
Mixed Architecture
Computers can store and process information using
binary variables (0 and 1)
The symbols 0 and 1 usually correspond to different voltage levels, where
0 is the low state, and 1 – high.
A binary o and 1 sequence represent
discrete (digital) information
There are ranges in every circuit for high and low state
Signed magnitude(SM)
LSB - Least Significant Bit
MSB - Most Significant
Alphanumeric codes
- ASCII (7 bits, 0-127)
- Unicode (8, 16, 32 systems; all characters)
- EBCDIC (faster than unicode)
Conjunction
AND * ^ &&
Disjunction
OR + ˅ ||
Negation
NOT – !
Annulment law
A * 0 = 0 ; A + 1 = 1
Identity law
A * 1 = A; A + 0 = A
Idempotent law
A * A = A; A + A = A
Commutative law
A + B = B + A; A * B = B * A
Complement law
A * !A = 0; A + !A = 1
Associative law
(A + B) + C = A + (B + C); (A * B) * C = A * (B * C)
Distributive law
(A + B) * C = A * C + B * C; (A * B) + C = (A + C) * (B + C)
Absorption law
A + (A * B) = A; A * (A + B) = A
Inversion law
!!A = A
De Morgan’s Laws
!(A * B) = !A + !B; !(A + B) = !A * !B
limit the current flowing in an electrical circuit, converts electrical energy into heat.
Resistors(R)
resistor with the possibility of changing the resistance by the user.
Potentiometer
small voltage high resistance, and vise-versa (used in receiver protection systems against damage caused by too high voltage)
Varistor
photosensitive element, the beam of light causes a decrease in its resistance (fire protection systems, temp measuring devices)
Photoresistor (F)
can accumulate electric charge, made of two conductors and dielectric layer
Capacitor (C)
conduct current in one direction and block its flow in the other
Diode (D)
used to rectify AC current
Rectifying diode
emitting the visible light and infrared range
LED
reacting to light
Photodiode
can conduct current in the opposite direction of traditional conductivity after reaching a specific voltage (breakdown voltage)
Zener diode
negative value of dynamic resistance after exceeding a particular value of forwarding voltage
Tunnel diode
are diodes that can change their capacitance (the ability to store electrical charge) when a voltage is applied to them in a certain direction
Capacitive diode
small capacitance of the connector, switching time about 100 ps. Can operate at frequency up to several dozen GHz (are diodes that have a very small capacitance, which means that they can switch electrical signals much faster than regular diodes)
Schottky diode
a three-electrode semiconductor electronic component, having the ability to amplify an electrical signal, in digital technology acts like a switch or key
Transistor (T)
stores energy in a magnetic field
Inductor (coil)
transfer AC electrical energy by induction from one electrical circuit to another
Transformer
are electronic devices that use a quartz crystal to generate a very precise and stable frequency. The quartz crystal vibrates at a specific frequency when an electrical current is applied to it
Crystal oscillator (X)
Combinational Circuit: input signal specifies output signals.
Sequential Circuit: like comb. Circ., but also depends on previous states
Digital Circuits
input signal specifies output signals.
Combinational Circuit
like comb. Circ., but also depends on previous states
Sequential Circuit
Using basic logical functions to create any logical function
Gates belong to comb. Circuits
Logic gates
Circuits with at least two inputs and most often two outputs,
Remember one bit of information.
Flip-flop
Built based on the flip-flops. Store digital information for a specific duration( >1 bit)
N = length of the register = number of flip-flops.
Capacity = 2^n, specifies max amount of different info that can be stored.
Registers
N = length of the register = number of flip-flops. Capacity =
2^n, specifies max amount of different info that can be stored.
Parallel entry and output of info simultaneously to all and from all entries in the register.
Simultaneous input and output of all bits.
Parallel register
Sequential input and output of bits.
Serial register
Serial input, parallel output.
Serial-Parallel
Parallel input, serial output.
Parallel-Serial
Count pulses and store the count.
Counter
circuit used to convert code 1 of n (ring) to another code (binary)
Convert multiple inputs to a single output code.
Encoder
used to convert code to code 1 of n.
Convert a single input code to multiple outputs.
Decoder
Code 1 of n has n inputs, with the one as highlighted state.
- Arithmetic Circuits: Perform binary addition.
- Types:
o Half Adder: Adds two bits, producing a sum and a carry-out.
o Full Adder: Adds three bits (two inputs and a carry-in), producing a sum and a carry-out.
o Ripple Carry Adder: Cascading full adders for multi-bit addition.
o Carry-Lookahead Adder: Faster addition by predicting carry propagation.
Adders
- Comparison Circuits: Determine the relative magnitude of two numbers.
- Types:
o Magnitude Comparator: Compares two numbers and outputs signals for greater than, less than, or equal to.
Comparators
Operation: Adds bits sequentially, one pair at a time, starting from the least significant bit (LSB).
Components:
Full adder
D flip-flop (to store the carry-out bit)
Process:
Input two bits and the previous carry-in.
The full adder produces a sum and a carry-out.
The sum is output, and the carry-out is stored in the D flip-flop.
In the next clock cycle, the next pair of bits and the stored carry-out are processed.
Advantages: Simple design.
Disadvantages: Slow operation due to sequential processing.
Serial Adder
Operation: Adds all bits simultaneously, using multiple full adders.
Components: Multiple full adders, one for each bit position.
Process:
All bits of the two numbers are input simultaneously.
The full adders in each position produce the sum and carry-out bits.
The carry-out from one position is fed as the carry-in to the next higher position.
Advantages: Fast operation due to parallel processing.
Disadvantages: Complex design, especially for larger numbers.
Parallel Adder
- Comparison Circuits: Determine the relative magnitude of two numbers.
- Types:
o Magnitude Comparator: Compares two numbers and outputs signals for greater than, less than, or equal to.
Comparators
- Data Selection/Distribution Circuits:
o Multiplexer: Selects one of many input signals and outputs it.
o Demultiplexer: Directs a single input signal to one of many output lines.
Multiplexers/Demultiplexers
Compares two numbers and outputs signals for greater than, less than, or equal to.
Magnitude Comparator
Selects one of many input signals and outputs it.
Multiplexer
Directs a single input signal to one of many output lines.
Demultiplexer
- Timing Circuits: Generate pulses of specific duration and frequency.
- Common Use: Clock signals for synchronous circuits.
Pulse Generators
- Miniaturized Electronic Circuits: Contain many transistors and other components.
- Integration Levels:
o SSI (Small-Scale Integration)
o MSI (Medium-Scale Integration)
o LSI (Large-Scale Integration)
o VLSI (Very-Large-Scale Integration)
o ULSI (Ultra-Large-Scale Integration)
Integrated Circuits (ICs)
o SSI (Small-Scale Integration)
o MSI (Medium-Scale Integration)
o LSI (Large-Scale Integration)
o VLSI (Very-Large-Scale Integration)
o ULSI (Ultra-Large-Scale Integration)
- SSI - Small Scale of Integration - up to 100 elements
- MSI - Medium Scale of Integration - 100 - 1000
- LSI - Large Scale of Integration - 103 - 105
- VLSI - Very Large Scale of Integration - over 105
- ULSI - Ultra Large Scale of Integration - over 106
Often referred to as the brain of the computer, is the central processing unit responsible for executing instructions. It performs arithmetic and logical operations based on a set of commands, essentially the program itself. Internally
The CPU
the CPU houses essential functional units:
Registers
Arithmetic Logic Unit (ALU)
Control Unit
These are high-speed, temporary storage locations that hold frequently accessed data and instructions during processing. Their size is typically a few bytes to hundreds of bytes, providing quick access for the CPU.
Registers
This unit performs arithmetic operations like addition, subtraction, multiplication, and division, along with logical operations like AND, OR, and NOT on binary data.
Arithmetic Logic Unit (ALU)
The control unit acts as the conductor of the CPU, fetching instructions from memory, decoding them, and directing other parts of the CPU to execute those instructions. It manages the flow of data within the CPU and communicates with other system components.
Control Unit
(Random Access Memory, 70 – 5 ns) – used to store currently processed data and the program, if we turn of a computer this information disappears
Primary Memory (RAM): Random Access Memory
(Read Only Memory they are slow 150 ns) – store important applications (POST – Power-On SelfTest- Teats of individual computer components, BIOS – Basic Input Output System- set of basic programs (drivers) for your computer’s devices, Bootstrap Loader – a program that searches for and loads the operating system into the operating memory)
Secondary Memory (ROM): Read-Only Memory
it is possible to change the program only once
PROM (Programmable Read-Only Memory)
the memory can be erased by the ultraviolet exposure, after which it is possible to reprogram it.
EPROM (Erasable Programmable Read-Only Memory)
– Erasing is done electrically (Flash memories)
EEPROM (Electrically Erasable Programmable Read-Only Memory)
collection of paths conducting electrical signals (Data, Address, Control)
act as data highways within the microprocessor system, enabling communication and data transfer between various components. They consist of multiple parallel lines that carry electrical signals. The number of lines determines the width of the bus, impacting the amount of data that can be transmitted simultaneously.
Buses
– transfer data between the processor and memory or IO chips
Data Bus = CPU buses
responsible for the appropriate addressing of orders and data (managed by microprocessor P)
Address Bus
control instructions that will determine what and how we want to do
Control Bus
store each bit of data in separate capacitors, requires periodic refresh
DRAM (Dynamic Random Access Memory): DRAM
stores data for as long as power is on, each bit is stored in a system consisting of four transistors (flip-flop) and to control transistors
SRAM (Static Random Access Memory): SRAM
are housed in modules for easier handling and installation. These modules connect to the motherboard’s memory slots and come in various standards that have evolved over time.
Memory chips
(Single In-Line Memory Module) : 30-pin module, 8-bit architecture, 4 modules in the bank for 32-bit transistors, 256kB up to 4MB, 11-bit address buss, access time 70 ns.
- Connector: 30-pin
- Architecture: 8-bit
- Modules per bank: 4 (for 32-bit systems)
- Capacity: 256KB to 4MB
- Address bus: 11-bit
- Access time: 70 ns
SIMM (Single In-Line Memory Module)
Dual IMM): double-sided edge connector, 168 pin in SDRAM, 64-bit organization, 184 pin in DDR, 240 pin in DDR2 and DDR3, small memory 256B
- Connector: Double-sided edge connector (168-pin in SDRAM, 184-pin in DDR, 240-pin in DDR2 and DDR3)
- Architecture: 64-bit
- Capacity: Smallest is 256MB
- Address bus: Varies depending on the standard (e.g., 168-pin SDRAM has a 64-bit data bus and a 32-bit address bus)
- Access time: Varies depending on the standard (e.g., DDR3 has faster access times than SDRAM)
DIMM (Dual In-Line Memory Module)
– transmits two words of data at each clock beat
DDR (Double Data Rate) SDRAM
