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Comparison Of Synchronous And Asynchronous Signalling
Synchronous and asynchronous transmissions are two different methods of transmission synchronization. Synchronous transmissions are synchronized by an external clock, while asynchronous transmissions are synchronized by special signals along the transmission medium. The need for synchronization Whenever an electronic device transmits digital (and sometimes analogue) data to another, there must be a certain rhythm established between the two devices, i.e., the receiving device must have some way of, within the context of the fluctuating signal that it's receiving, determining where each unit of data begins and where it ends. Methods of synchronization There are two ways to synchronize the two ends of the communication. The synchronous signalling methods use two different signals. A pulse on one signal indicates when another bit of information is ready on the other signal. The asynchronous signalling methods use only one signal. The receiver uses transitions on that signal to f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Transmission
Data communication, including data transmission and data reception, is the transfer of data, signal transmission, transmitted and received over a Point-to-point (telecommunications), point-to-point or point-to-multipoint communication channel. Examples of such channels are copper wires, optical fibers, wireless communication using radio spectrum, storage media and computer buses. The data are represented as an electromagnetic signal, such as an electrical voltage, radiowave, microwave, or infrared signal. ''Analog transmission'' is a method of conveying voice, data, image, signal or video information using a continuous signal that varies in amplitude, phase, or some other property in proportion to that of a variable. The messages are either represented by a sequence of pulses by means of a line code (''baseband transmission''), or by a limited set of continuously varying waveforms (''passband transmission''), using a digital modulation method. The passband modulation and cor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synchronization
Synchronization is the coordination of events to operate a system in unison. For example, the Conductor (music), conductor of an orchestra keeps the orchestra synchronized or ''in time''. Systems that operate with all parts in synchrony are said to be synchronous or ''in sync''—and those that are not are ''Asynchronous system, asynchronous''. Today, time synchronization can occur between systems around the world through satellite navigation signals and other time and frequency transfer techniques. Navigation and railways Time-keeping and synchronization of clocks is a critical problem in long-distance ocean navigation. Before radio navigation and Radionavigation-satellite service, satellite-based navigation, navigators required accurate time in conjunction with astronomical observations to determine History of longitude, how far east or west their vessel traveled. The invention of an accurate marine chronometer revolutionized marine navigation. By the end of the 19th cent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronic Device
Electronics is a scientific and engineering discipline that studies and applies the principles of physics to design, create, and operate devices that manipulate electrons and other electrically charged particles. It is a subfield of physics and electrical engineering which uses active devices such as transistors, diodes, and integrated circuits to control and amplify the flow of electric current and to convert it from one form to another, such as from alternating current (AC) to direct current (DC) or from analog signals to digital signals. Electronic devices have significantly influenced the development of many aspects of modern society, such as telecommunications, entertainment, education, health care, industry, and security. The main driving force behind the advancement of electronics is the semiconductor industry, which continually produces ever-more sophisticated electronic devices and circuits in response to global demand. The semiconductor industry is one of the gl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autobaud
Automatic baud rate detection (ABR, autobaud) refers to the process by which a receiving device (such as a modem) determines the speed, code level, start bit, and stop bits of incoming data by examining the first character, usually a preselected sign-on character (syncword) on a UART connection. ABR allows the receiving device to accept data from a variety of transmitting devices operating at different speeds without needing to establish data rates in advance. Process During the autobaud process, the baud rate of received character stream is determined by examining the received pattern and its timing, and the length of a start bit. These types of baud rate detection mechanisms are supported by many hardware chips including processors such as STM32 MPC8280, MPC8360, and so on. When start bit length is used to determine the baud rate, it requires the character to be odd since UART sends LSB bit firstthis particular bit order scheme is referred to as little-endian. Often ASCII ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phase-locked Loop
A phase-locked loop or phase lock loop (PLL) is a control system that generates an output signal whose phase is fixed relative to the phase of an input signal. Keeping the input and output phase in lockstep also implies keeping the input and output frequencies the same, thus a phase-locked loop can also track an input frequency. Furthermore, by incorporating a frequency divider, a PLL can generate a stable frequency that is a multiple of the input frequency. These properties are used for clock synchronization, demodulation, frequency synthesis, clock multipliers, and signal recovery from a noisy communication channel. Since 1969, a single integrated circuit can provide a complete PLL building block, and nowadays have output frequencies from a fraction of a hertz up to many gigahertz. Thus, PLLs are widely employed in radio, telecommunications, computers (e.g. to distribute precisely timed clock signals in microprocessors), grid-tie inverters (electronic power converters used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parallel Communications
In data transmission, parallel communication is a method of conveying multiple binary digits (bits) simultaneously using multiple conductors. This contrasts with serial communication, which conveys only a single bit at a time; this distinction is one way of characterizing a communications link. The basic difference between a parallel and a serial communication channel is the number of electrical conductors used at the physical layer to convey bits. Parallel communication implies more than one such conductor. For example, an 8-bit parallel channel will convey eight bits (or a byte) simultaneously, whereas a serial channel would convey those same bits sequentially, one at a time. If both channels operated at the same clock speed, the parallel channel would be eight times faster. A parallel channel may have additional conductors for other signals, such as a clock signal to pace the flow of data, a signal to control the direction of data flow, and Handshake (computing), handshaking s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Address Bus
In computer architecture, a bus (historically also called a data highway or databus) is a communication system that transfers data between components inside a computer or between computers. It encompasses both hardware (e.g., wires, optical fiber) and software, including communication protocols. At its core, a bus is a shared physical pathway, typically composed of wires, traces on a circuit board, or busbars, that allows multiple devices to communicate. To prevent conflicts and ensure orderly data exchange, buses rely on a communication protocol to manage which device can transmit data at a given time. Buses are categorized based on their role, such as system buses (also known as internal buses, internal data buses, or memory buses) connecting the CPU and memory. Expansion buses, also called peripheral buses, extend the system to connect additional devices, including peripherals. Examples of widely used buses include PCI Express (PCIe) for high-speed internal connectio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Control Bus
In computer architecture, a control bus is part of the system bus and is used by central processing unit, CPUs for communicating with other devices within the computer. While the address bus carries the information about the device with which the CPU is communicating and the Bus (computing), data bus carries the actual data being processed, the control bus carries commands from the CPU and returns status signals from the devices. For example, if the data is being read or written to the device the appropriate line (read or write) will be active (logic one). Lines The number and type of lines in a control bus varies but there are basic lines common to all microprocessors, such as: * Read (\overline ). A single line that when active (logic zero) indicates the device is being read by the CPU. * Write (\overline ). A single line that when active (logic zero) indicates the device is being written by the CPU. * Byte enable (\overline E). A group of lines that indicate the size of the d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asynchronous Start-stop
Asynchronous serial communication is a form of serial communication in which the communicating endpoints' interfaces are not continuously synchronized by a common clock signal. Synchronization (clock recovery) is done by data-embedded signal: the data stream contains synchronization information in a form of start and stop signals set before and after each payload transmission. The start signal prepares the receiver for arrival of data and the stop signal resets its state to enable triggering of a new sequence. A common kind of start-stop transmission is ASCII over RS-232, for example for use in teletypewriter operation. Origin Mechanical teleprinters using 5-bit codes (see Baudot code) typically used a stop period of 1.5 bit times.Dead link: 2015-Oct-03 Very early electromechanical teletypewriters (pre-1930) could require 2 stop bits to allow mechanical impression without buffering. Hardware which does not support fractional stop bits can communicate with a device that uses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maxim Integrated
Maxim Integrated Products, Inc., was an American semiconductor company that designed, manufactured, and sold analog and mixed-signal integrated circuits for the automotive, industrial, communications, consumer, and computing markets. Maxim's product portfolio included power and battery management ICs, sensors, analog ICs, interface ICs, communications solutions, digital ICs, embedded security, and microcontrollers. The company is headquartered in San Jose, California, and has design centers, manufacturing facilities, and sales offices worldwide. In 2021, the company was acquired by Analog Devices. History Maxim was founded in April 1983. The founding team included Jack Gifford, a semiconductor industry pioneer since the 1960s and co-founder of Advanced Micro Devices; Fred Beck, an IC sales and distribution pioneer; Dave Bingham, General Electric’s Scientist of the Year in 1982; Steve Combs, a pioneer in wafer technologies and manufacturing; Lee Evans, also a pioneer in CMOS a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bit Rate
In telecommunications and computing, bit rate (bitrate or as a variable ''R'') is the number of bits that are conveyed or processed per unit of time. The bit rate is expressed in the unit bit per second (symbol: bit/s), often in conjunction with an SI prefix such as kilo (1 kbit/s = 1,000 bit/s), mega (1 Mbit/s = 1,000 kbit/s), giga (1 Gbit/s = 1,000 Mbit/s) or tera (1 Tbit/s = 1,000 Gbit/s). The non-standard abbreviation bps is often used to replace the standard symbol bit/s, so that, for example, 1 Mbps is used to mean one million bits per second. In most computing and digital communication environments, one byte per second (symbol: B/s) corresponds roughly to 8 bit/s. However if stop bits, start bits, and parity bits need to be factored in, a higher number of bits per second will be required to achieve a throughput of the same number of bytes. Prefixes When quantifying large or small bit rates, SI ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
