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SENT (protocol)
The SAE J2716 SENT (Single Edge Nibble Transmission) protocol is a point-to-point scheme for transmitting signal values from a sensor to a controller. It is intended to allow for transmission of high resolution data with a low system cost. Hardware The SENT protocol is a one-way, asynchronous voltage interface which requires three wires: a signal line (low state 4.1 V), a supply voltage line (5 V) and a ground line. SENT uses pulse-width modulation to encode four bits (one nibble) per symbol. The basic unit of time in SENT is called a tick, where a tick can be between 3 - 90 µs, at the sender's option. Each message is preceded by a calibration pulse with a high period of 56 ticks for framing and calibration of tick length. After the calibration pulse, each nibble is transmitted with a fixed-width low signal, followed by a variable-length high period. The low-period is 5 (or more) ticks in length, while the high period can vary, for a total time between falling edg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications Protocol
A communication protocol is a system of rules that allows two or more entities of a communications system to transmit information via any kind of variation of a physical quantity. The protocol defines the rules, syntax, semantics and synchronization of communication and possible error recovery methods. Protocols may be implemented by hardware, software, or a combination of both. Communicating systems use well-defined formats for exchanging various messages. Each message has an exact meaning intended to elicit a response from a range of possible responses pre-determined for that particular situation. The specified behavior is typically independent of how it is to be implemented. Communication protocols have to be agreed upon by the parties involved. To reach an agreement, a protocol may be developed into a technical standard. A programming language describes the same for computations, so there is a close analogy between protocols and programming languages: ''protocols ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Universal Asynchronous Receiver/transmitter
A universal asynchronous receiver-transmitter (UART ) is a computer hardware device for asynchronous serial communication in which the data format and transmission speeds are configurable. It sends data bits one by one, from the least significant to the most significant, framed by start and stop bits so that precise timing is handled by the communication channel. The electric signaling levels are handled by a driver circuit external to the UART. Two common signal levels are RS-232, a 12-volt system, and RS-485, a 5-volt system. Early teletypewriters used current loops. It was one of the earliest computer communication devices, used to attach teletypewriters for an operator console. It was also an early hardware system for the Internet. A UART is usually an individual (or part of an) integrated circuit (IC) used for serial communications over a computer or peripheral device serial port. One or more UART peripherals are commonly integrated in microcontroller chips. Specialised ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulse-width Modulation
Pulse-width modulation (PWM), or pulse-duration modulation (PDM), is a method of reducing the average power delivered by an electrical signal, by effectively chopping it up into discrete parts. The average value of voltage (and current) fed to the load is controlled by turning the switch between supply and load on and off at a fast rate. The longer the switch is on compared to the off periods, the higher the total power supplied to the load. Along with maximum power point tracking (MPPT), it is one of the primary methods of reducing the output of solar panels to that which can be utilized by a battery. PWM is particularly suited for running inertial loads such as motors, which are not as easily affected by this discrete switching, because their inertia causes them to react slowly. The PWM switching frequency has to be high enough not to affect the load, which is to say that the resultant waveform perceived by the load must be as smooth as possible. The rate (or frequency) a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nibble
In computing, a nibble (occasionally nybble, nyble, or nybl to match the spelling of byte) is a four-bit aggregation, or half an octet. It is also known as half-byte or tetrade. In a networking or telecommunication context, the nibble is often called a semi-octet, quadbit, or quartet. A nibble has sixteen () possible values. A nibble can be represented by a single hexadecimal digit (–) and called a hex digit. A full byte (octet) is represented by two hexadecimal digits (–); therefore, it is common to display a byte of information as two nibbles. Sometimes the set of all 256-byte values is represented as a table, which gives easily readable hexadecimal codes for each value. Four-bit computer architectures use groups of four bits as their fundamental unit. Such architectures were used in early microprocessors, pocket calculators and pocket computers. They continue to be used in some microcontrollers. In this context, 4-bit groups were sometimes also called ''characters' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclic Redundancy Check
A cyclic redundancy check (CRC) is an error-detecting code commonly used in digital networks and storage devices to detect accidental changes to digital data. Blocks of data entering these systems get a short ''check value'' attached, based on the remainder of a polynomial division of their contents. On retrieval, the calculation is repeated and, in the event the check values do not match, corrective action can be taken against data corruption. CRCs can be used for error correction (see bitfilters). CRCs are so called because the ''check'' (data verification) value is a ''redundancy'' (it expands the message without adding information) and the algorithm is based on ''cyclic'' codes. CRCs are popular because they are simple to implement in binary hardware, easy to analyze mathematically, and particularly good at detecting common errors caused by noise in transmission channels. Because the check value has a fixed length, the function that generates it is occasionally used as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SENT Protocol Exemple, With A 12us TickTime And 8 Nibbles
Sent is a former municipality in the district of Inn in the Swiss Canton of Graubünden. On 1 January 2015 the former municipalities of Ardez, Guarda, Tarasp, Ftan and Sent merged into the municipality of Scuol.Amtliches Gemeindeverzeichnis der Schweiz published by the Swiss Federal Statistical Office accessed 27 April 2016 History Sent is first mentioned in 930, when King sent the priest Hartpert to the church in ''vicus Sindes''. It is unclear whether he meant the Chur ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Network Buses
List of electrical characteristics of single collision domain segment "slow speed" network buses: {, class="wikitable sortable" style="width:100%;" ! Name !! Multidrop !! Max nodes !! Electrical type !! Cable type !! data-sort-type="number", Max bitrate [kbit/s] !data-sort-type="number", Length at max bitrate!! data-sort-type="number" , Max length [m] !data-sort-type="number", Bitrate at max length , - , , , , , , , , , , , , , , , , - , EIA-485 , , Y , , 256 , , EIA-485 , , Twisted pair , , , , , , , - , SCSI-1/2 , , Y , , 8 , , Open collector , , Ribbon cable , , , , , , , - , SCSI Ultra2 , , Y , , 16 , , EIA-485 , , Twisted pair , , , , , , , - , LIN, , Y , , 16 , , Open collector, , open collector with pull-up to 12V car supply , , , , , , - , SIOX , , Y , , 62 , , , , , , , , , , , - , I²C , , Y , , 127 or 1023 , , Open collector , , , , , , , , , - , SMBus , , Y , , 128 , , Open co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Transmission
Data transmission and data reception or, more broadly, data communication or digital communications is the transfer and reception of data in the form of a digital bitstream or a digitized analog signal transmitted over a 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 which 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 modulat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
