This time out, the base is a keytar, built using eight bits.
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A byte is eight bits, a series of eight ones and zeros.
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A one-bit pixel can only represent black or white; eight bits allows for the unique representation of 256 grayscale states between black and white; 24 bits gives us RGB color, with eight bits representing each of the red, blue, and green components for 16,777,216 possible colors.
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Through loops, eight-bits and inventive arrangements, he's made a critical addition to his work that may inspire awe even in the most ambivalent.
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For the audiophiles among you, it was a PCM encoding of only eight bits, in mono, and with a sampling frequency of just eight kilohertz.
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Eight bits make a byte; the active working memory of a typical smartphone might employ something like 2 gigabytes, or two times 8 billion bits.
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Eight bits were arranged together to form one byte, which is enough to encode a single letter in the standard computer scheme used to represent text.
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He liked to distract himself with thought experiments: If he could send his past self a message that was limited to only eight bits, what would it be?
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A byte is eight bits (each bit is a 0 or 1), and in common encodings, a single letter is equivalent to eight 0s and 83s in a row.
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Released in 1989, the Game Boy racked up a significant amount of games for a handheld system with four AA batteries, eight bits, no backlight, and an olive green screen that looked like a regular Nintendo game had experienced copper oxidation.
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A collection of eight bits — known as a byte — can store a single character, like the letter A. A quantum computer, on the other hand, processes bits built by scientists that can exist as both a 1 and a 0 simultaneously.
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The octet is a unit of digital information in computing and telecommunications that consists of eight bits. The term is often used when the term byte might be ambiguous, as the byte has historically been used for storage units of a variety of sizes. The term octad(e) for eight bits is no longer common.
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Having this hindsight, some ten years later, CEPT chose eight bits for framing the European E1, although, as feared, the extra channel is sometimes appropriated for voice or data.
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A common choice then was the 36-bit word, which is also a good size for the numeric properties of a floating point format. After the introduction of the IBM System/360 design, which used eight-bit characters and supported lower-case letters, the standard size of a character (or more accurately, a byte) became eight bits. Word sizes thereafter were naturally multiples of eight bits, with 16, 32, and 64 bits being commonly used.
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However, it would require all data transmission to send eight bits when seven could suffice. The committee voted to use a seven-bit code to minimize costs associated with data transmission. Since perforated tape at the time could record eight bits in one position, it also allowed for a parity bit for error checking if desired. Eight-bit machines (with octets as the native data type) that did not use parity checking typically set the eighth bit to 0.
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The term octet is used to unambiguously specify a size of eight bits. It is used extensively in protocol definitions. Historically, the term octad or octade was used to denote eight bits as well at least in Western Europe; however, this usage is no longer common. The exact origin of the term is unclear, but it can be found in British, Dutch, and German sources of the 1960s and 1970s, and throughout the documentation of Philips mainframe computers.
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Each round, the left 64 bits of the register form the subkey, and right eight bits form the ICB bits. After each round, the register is rotated 56 bits to the left.
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The four-of-eight code was a 64 character set plus six control characters, encoded in eight bits. Exactly four bits of each character were one bits -- there are 70 such possible bit combinations.
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Ascii85, also called Base85, is a form of binary-to-text encoding developed by Paul E. Rutter for the btoa utility. By using five ASCII characters to represent four bytes of binary data (making the encoded size larger than the original, assuming eight bits per ASCII character), it is more efficient than uuencode or Base64, which use four characters to represent three bytes of data ( increase, assuming eight bits per ASCII character). Its main modern uses are in Adobe's PostScript and Portable Document Format file formats, as well as in the patch encoding for binary files used by Git.
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Vectored interrupts are achieved by assigning each interrupting device a unique code, typically four to eight bits in length. When a device interrupts, it sends its unique code over the data bus to the processor, telling the processor which interrupt service routine to execute.
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Receivers subtract this offset from GPS time to calculate UTC and specific time zone values. New GPS units may not show the correct UTC time until after receiving the UTC offset message. The GPS-UTC offset field can accommodate 255 leap seconds (eight bits).
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It is also consistent with the other uses of the SI prefixes in computing, such as CPU clock speeds or measures of performance. The IEC 80000-13 standard uses the term 'byte' to mean eight bits (1 B = 8 bit). Therefore, 1 kB = 8000 bit.
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They are also selected to maintain DC balance of the encoded sequence. Thus, in the final analysis, seventeen bits of disc space are needed to encode eight bits of data. Tekla S. Perry. "Kees Immink: The Man Who Put Compact Discs on Track". 2017\.
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Most modern computers are byte-addressable. Each address identifies a single byte (eight bits) of storage. Data larger than a single byte may be stored in a sequence of consecutive addresses. There exist word-addressable computers, where the minimal addressable storage unit is exactly the processor's word.
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Slots and tables are trivially computed from hashes. The target table is simply the lowest eight bits of the hash (i.e. hash modulo 256), and the slot within the table is the remaining bits of the hash modulo the table length (i.e. hash divided by 256 modulo table length).
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For images with a modest range of brightnesses from the darkest to the lightest, eight bits per primary color provides good-quality images, but extreme images require more bits per primary color as well as the advanced display technology. For more information see High Dynamic Range (HDR) imaging.
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On most modern computing platforms this is eight bits. The result of sizeof has an unsigned integral type that is usually denoted by size_t. The operator has a single operand, which is either an expression or a data type cast. A cast is a data type enclosed in parenthesis.
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The 305 was one of the last vacuum tube computers that IBM built. It weighed over a ton. The IBM 350 disk system stored 5 million alphanumeric characters recorded as six data bits, one parity bit and one space bit for eight bits recorded per character. It had fifty disks.
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The hardware of the BBC Micro was emulated by a single customized ULA chip designed by Acorn in conjunction with Ferranti. It had feature limitations such as the inability to output more than one channel of sound or provide teletext mode. By contrast, the BBC Micro was capable of three-way polyphony (plus one noise channel). The edge connector on the rear of the Electron exposes all address and data bus lines from the CPU, including the upper eight bits of the address bus, in contrast to the limited selection available via the BBC Micro's expansion ports, with the One Megahertz Bus as the principal mechanism for general purpose expansion on the BBC Micro only providing the lower eight bits of the address bus.
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The lowercase letter o for octet is defined as the symbol for octet in IEC 80000-13 and is commonly used in languages such as French and Romanian, and is also combined with metric prefixes for multiples, for example ko and Mo. The usage of the term octad(e) for eight bits is no longer common.
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The term octet always refers to an 8-bit quantity. It is mostly used in the field of computer networking, where computers with different byte widths might have to communicate. In modern usage byte almost invariably means eight bits, since all other sizes have fallen into disuse; thus byte has come to be synonymous with octet.
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To allow for the identification of information bits within a frame, two alternatives were considered. Assign (a) just one extra bit, or (b) additional eight bits per frame. The 8-bit choice is cleaner, resulting in a 200-bit frame, twenty-five 8-bit channels, of which 24 are traffic and one 8-bit channel available for operations, administration, and maintenance (OA&M;).
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It sings of darkness, blindness, and fear, but it sings also of complexity, connection, redemption, and hope." Adam Feldman of Time Out New York gave Octet 5 ouf of 5 stars and wrote: "Under Annie Tippe’s taut direction, all eight bits of Octet’s byte-size cast perform Malloy’s challenging compositions with exceptional skill, abetted by Or Matias’s musical direction and Hidenori Nakajo’s sound design.
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Controlling a Selectrix locomotive decoder takes one SX address with its eight bits. Therefore, one Selectrix bus can control maximum 112 locomotives simultaneously. If the system central unit is equipped with more than one SX bus, only the first one (SX0) is connected to the track and can be used to control locomotives. In some control throttles, only locomotive addresses 1-99 can be selected.
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On most modern computers, the smallest data group with an address is eight bits long and is called a byte. Larger groups comprise two or more bytes, for example, a 32-bit word contains four bytes. There are two possible ways a computer could number the individual bytes in a larger group, starting at either end. Both types of endianness are in widespread use in digital electronic engineering.
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In this mode the selected character codes are encapsulated, which reduces the performance by about 0.4% + additional 0.4% for every selected character code. In case the data link is limited to seven data bits, a special bit collection mode can be activated. The highest bits for every seven bytes are collected to one byte (which is eight bits under normal conditions). This collection reduces the performance about 12.4% and doubles the character encapsulation capacity.
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However, the unit byte has historically been platform-dependent and has represented various storage sizes in the history of computing. Due to the influence of several major computer architectures and product lines, the byte became overwhelmingly associated with eight bits. This meaning of byte is codified in such standards as ISO/IEC 80000-13. While byte and octet are often used synonymously, those working with certain legacy systems are careful to avoid ambiguity.
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Octets can be represented using number systems of varying bases such as the hexadecimal, decimal, or octal number systems. The binary value of all eight bits set (or activated) is , equal to the hexadecimal value , the decimal value , and the octal value . One octet can be used to represent decimal values ranging from 0 to 255. The term octet (symbol: o) is often used when the use of byte might be ambiguous.
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Modern architectures typically use 32- or 64-bit words, built of four or eight bytes. The unit symbol for the byte was designated as the upper-case letter B by the International Electrotechnical Commission (IEC) and Institute of Electrical and Electronics Engineers (IEEE) in contrast to the bit, whose IEEE symbol is a lower-case b. Internationally, the unit octet, symbol o, explicitly defines a sequence of eight bits, eliminating the ambiguity of the byte.
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For 8-N-1 encoding, only 80% of the bits are available for data (for every eight bits of data, ten bits are sent over the serial link -- one start bit, the eight data bits, and the one stop bit). This mode was also commonplace for the link between modems until the 1990s when Link Access Procedure for Modems (LAPM) became widespread. 8-N-1 continued in use for the computer to modem connection.
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In the C programming language, operations can be performed on a bit level using bitwise operators. Bitwise operations are contrasted by byte-level operations which characterize the bitwise operators' logical counterparts, the AND, OR and NOT operators. Instead of performing on individual bits, byte- level operators perform on strings of eight bits (known as bytes) at a time. The reason for this is that a byte is normally the smallest unit of addressable memory (i.e.
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0.1 is commonly written as 127.1, given that it belongs to a class-A network with eight bits for the network mask and 24 bits for the host number. When fewer than four numbers are specified in the address in dotted notation, the last value is treated as an integer of as many bytes as are required to fill out the address to four octets. Thus, the address 127.65530 is equivalent to 127.0.255.250.
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The only primitive data type in the Plankalkül is a single bit or boolean ( - yes-no value in Zuses terminology). It is denoted by the identifier S0. All the further data types are composite, and build up from primitive by means of "arrays" and "records". So, a sequence of eight bits (which in modern computing could be regarded as byte) is denoted by 8 \times S0, and boolean matrix of size m by n is described by m \times n \times S0.
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As the scheme name suggests, eight bits of data are transmitted as a 10-bit entity called a symbol, or character. The low five bits of data are encoded into a 6-bit group (the 5b/6b portion) and the top three bits are encoded into a 4-bit group (the 3b/4b portion). These code groups are concatenated together to form the 10-bit symbol that is transmitted on the wire. The data symbols are often referred to as D.x.
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JPEG (Joint Photographic Experts Group) is a lossy compression method; JPEG-compressed images are usually stored in the JFIF (JPEG File Interchange Format) file format. The JPEG/JFIF filename extension is JPG or JPEG. Nearly every digital camera can save images in the JPEG/JFIF format, which supports eight-bit grayscale images and 24-bit color images (eight bits each for red, green, and blue). JPEG applies lossy compression to images, which can result in a significant reduction of the file size.
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A frame is a series of bits generally composed of frame synchronization bits, the packet payload, and a frame check sequence. Examples are Ethernet frames, Point-to-Point Protocol (PPP) frames, Fibre Channel frames, and V.42 modem frames. Often, frames of several different sizes are nested inside each other. For example, when using Point-to-Point Protocol (PPP) over asynchronous serial communication, the eight bits of each individual byte are framed by start and stop bits, David S.Lawyer and Greg Hankins.
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In this version, the significand is stored as a series of decimal digits. The leading digit is between 0 and 9 (3 or 4 binary bits), and the rest of the significand uses the densely packed decimal (DPD) encoding. The leading 2 bits of the exponent and the leading digit (3 or 4 bits) of the significand are combined into the five bits that follow the sign bit. This eight bits after that are the exponent continuation field, providing the less-significant bits of the exponent.
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In a shifted code, some character codes determine choices between options for the following character codes. It allows compact encoding, but is less reliable for data transmission, as an error in transmitting the shift code typically makes a long part of the transmission unreadable. The standards committee decided against shifting, and so ASCII required at least a seven-bit code. The committee considered an eight-bit code, since eight bits (octets) would allow two four-bit patterns to efficiently encode two digits with binary-coded decimal.
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However, because of the ambiguity of relying on the underlying hardware design, the unit octet was defined to explicitly denote a sequence of eight bits. Computers usually manipulate bits in groups of a fixed size, conventionally named "words". Like the byte, the number of bits in a word also varies with the hardware design, and is typically between 8 and 80 bits, or even more in some specialized computers. In the 21st century, retail personal or server computers have a word size of 32 or 64 bits.
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The 65C816 has two operating modes, "emulation mode," in which the 16-bit operations are invisible—the index registers are forced to eight bits— and the chip appears to be very similar to the 65C02, with to the same cycle timings for the opcodes, and "native mode," which exposes all new features. The CPU automatically returns to emulation mode when it is powered on or reset, which allows it to replace a 65C02, assuming one makes the required circuit changes to accommodate the different pin layout.
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Daniel M. Dobkin, The RF in RFID: Passive UHF RFID In Practice, Newnes 2008 , chapter 8 An Electronic Product Code (EPC) is one common type of data stored in a tag. When written into the tag by an RFID printer, the tag contains a 96-bit string of data. The first eight bits are a header which identifies the version of the protocol. The next 28 bits identify the organization that manages the data for this tag; the organization number is assigned by the EPCGlobal consortium.
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The master sends a bit on the MOSI line and the slave reads it, while the slave sends a bit on the MISO line and the master reads it. This sequence is maintained even when only one-directional data transfer is intended. Transmissions normally involve two shift registers of some given word-size, such as eight bits, one in the master and one in the slave; they are connected in a virtual ring topology. Data is usually shifted out with the most significant bit first.
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If a key were eight bits (one byte) long, the keyspace would consist of 28 or 256 possible keys. Advanced Encryption Standard (AES) can use a symmetric key of 256 bits, resulting in a key space containing 2256 (or 1.1579 × 1077) possible keys. In the DES block cipher, 56-bit key is used, resulting in a relatively small key space of size 256 (or 7.2058 x 1016), which, as was demonstrated in 1998, can be searched exhaustively in 56 hours with a desktop computer.
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Historically, the baudot and braille keyboards were standardized to some extent, but they are unable to replicate the full character set of a modern keyboard. Braille comes closest, as it has been extended to eight bits. The only proposed modern standard, GKOS (or Global Keyboard Open Standard) can support most characters and functions found on a computer keyboard but has had little commercial development. There is, however, a GKOS keyboard application available for iPhone since May 8, 2010, for Android since October 3, 2010 and for MeeGo Harmattan since October 27, 2011.
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Some special-purpose protocols such as MIDI for musical instrument control, use serial data rates other than the teleprinter standards. Some serial port implementations can automatically choose a bit rate by observing what a connected device is sending and synchronizing to it. The total speed includes bits for framing (stop bits, parity, etc.) and so the effective data rate is lower than the bit transmission rate. For example, with 8-N-1 character framing, only 80% of the bits are available for data; for every eight bits of data, two more framing bits are sent.
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The aim of monitoring errors is to continuously check transmission quality without disturbing the information traffic and, when this quality is not of the required standard, taking the necessary steps to improve it. Telephone traffic is two way, which means that information is transmitted in both directions between the ends of the communication. This in its turn means that two 2 Mbit/s channels and two directions for transmission must be considered. The CRC-4 multiframe alignment word only takes up six of the first eight bits of the TS0 without FAS.
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The modern de facto standard of eight bits, as documented in ISO/IEC 2382-1:1993, is a convenient power of two permitting the binary-encoded values 0 through 255 for one byte—2 to the power 8 is 256. The international standard IEC 80000-13 codified this common meaning. Many types of applications use information representable in eight or fewer bits and processor designers optimize for this common usage. The popularity of major commercial computing architectures has aided in the ubiquitous acceptance of the eight-bit size.
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Many programming languages defined the data type byte. The C and C++ programming languages define byte as an "addressable unit of data storage large enough to hold any member of the basic character set of the execution environment" (clause 3.6 of the C standard). The C standard requires that the integral data type unsigned char must hold at least 256 different values, and is represented by at least eight bits (clause 5.2.4.2.1). Various implementations of C and C++ reserve 8, 9, 16, 32, or 36 bits for the storage of a byte.
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6502 instruction operation codes (opcodes) are eight-bits long and have the general form AAABBBCC, where AAA and CC define the opcode, and BBB defines the addressing mode. For instance, consider the `ORA` instruction, which performs a bitwise OR on the bits in the accumulator with another value. The instruction opcode is of the form 000bbb01, where bbb may be 010 for an immediate mode value (constant), 001 for zero page fixed address, 011 for an absolute address, and so on. This pattern is not absolute and there are a number of exceptions.
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A framebuffer is a digital device for computers which stores data in the so-called video memory (comprising an array of Video RAM or similar chips). This data goes either to three digital-to-analog converters (DACs) (for analog monitors), one per primary color or directly to digital monitors. Driven by software, the CPU (or other specialized chips) write the appropriate bytes into the video memory to define the image. Modern systems encode pixel color values by devoting eight bits to each of the R, G, and B components.
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During these wait cycles, additional commands may be sent to other banks; because each bank operates completely independently. Both read and write commands require a column address. Because each chip accesses eight bits of data at a time, there are 2,048 possible column addresses thus requiring only 11 address lines (A0-A9, A11). When a read command is issued, the SDRAM will produce the corresponding output data on the DQ lines in time for the rising edge of the clock a few clock cycles later, depending on the configured CAS latency.
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Line signaling can be conveyed in a single DS0 channel of a trunk. In modern PCM telecommunications, line signaling is represented by the ABCD bits in DS0 #16 of an E1 or a selected DS0 within a T1. Line signaling can also be conveyed within the channels being supervised, as in the original T1 scheme which used one out of every eight bits for supervision, or with robbed bits of a superframe format, or as in-band signaling, e.g. as in L1 signaling where 2280 Hz tone pulses are used.
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A single-byte buffer was used to send and receive data; every time the clock signal toggled, one bit from the buffer would be read or written. When all eight bits were read or written, the system generated an interrupt that triggered the operating system to read or write more data. Unlike a cassette interface, where only a single device would normally be used, an external expansion port would need to be able to support more than one device. To support this, a simple protocol was developed and several new pins added to the original simple cassette port.
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FOCAL's PDP-8 implementation used a floating point representation that represented numbers as four 12-bit words, forty-eight bits in total, with thirty-six bits of mantissa and twelve bits of exponent. This allowed for both significantly higher precision and a significantly wider range of values than most contemporary interpreters, making FOCAL a reasonable choice for serious numerical work. This high precision, and good choices for default decimal output formatting, meant that difficulties with binary-to- decimal rounding were not evident to beginning users. For comparison, Microsoft BASIC initially used a 32-bit format, while later versions expanded this to 40-bits.
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Related to numeric representation is the size and precision of integer numbers that a CPU can represent. In the case of a binary CPU, this is measured by the number of bits (significant digits of a binary encoded integer) that the CPU can process in one operation, which is commonly called word size, bit width, data path width, integer precision, or integer size. A CPU's integer size determines the range of integer values it can directly operate on. For example, an 8-bit CPU can directly manipulate integers represented by eight bits, which have a range of 256 (28) discrete integer values.
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A color image is usually stored in memory as a raster map, a two-dimensional array of small integer triplets; or (rarely) as three separate raster maps, one for each channel. Separate R, G, and B image layers Eight bits per sample (24 bits per pixel) seem adequate for most uses, but faint banding artifacts may still be visible in some smoothly varying images, especially those subject to processing. Particularly demanding applications may use 10 bits per sample or more. On the other hand, some widely used image file formats and graphics cards may use only 8 bits per pixel, i.e.
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The octet is used to represent Internet Protocol computer network addresses. An IPv4 address consists of four octets, usually shown individually as a series of decimal values ranging from 0 to 255, each separated by a full stop (dot). Using octets with all eight bits set, the representation of the highest numbered IPv4 address is 255.255.255.255. An IPv6 address consists of sixteen octets, shown using hexadecimal representation (two digits per octet) and using a colon character (:) after each pair of octets (16 bits also known as hextet) for readability, like this FE80:0000:0000:0000:0123:4567:89AB:CDEF.
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The VIDC1 can use a color depth of 1, 2, 4 or eight bits per color, from monochrome to 4 to 16 to 256 colors (the VIDC20 can go up to 16 million colors). Also included is a very small color lookup table, just 16 12-bit words, (4096 colors, in 4 bit mode). The 12 bits were split in three 4-bit RGB values, with a 4-bit high speed D-A converter for each of the three primary colors. Its single "sprite" was used for a hardware mouse pointer, which could have three different colors (two bit per pixel, including transparent).
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Despite the definitions of these new prefixes for binary-based quantities of storage by international standards organizations, memory semiconductor chips are still marketed using the metric prefix names to designate binary multiples. Using the common byte size of eight bits and the standardized metric definition of megabit and kilobyte, 1 megabit is equal to 125 kilobytes (kB) or approximately 122 kibibytes (KiB). The megabit is widely used when referring to data transfer rates of computer networks or telecommunications systems. Network transfer rates and download speeds often use the megabit as the amount transferred per time unit, e.g.
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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 handshaking signals. Parallel communication is and always has been widely used within integrated circuits, in peripheral buses, and in memory devices such as RAM.
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For example, a binary string of eight bits can represent any of 256 possible values and can, therefore, represent a wide variety of different items. In computing and telecommunications, binary codes are used for various methods of encoding data, such as character strings, into bit strings. Those methods may use fixed-width or variable-width strings. In a fixed-width binary code, each letter, digit, or other character is represented by a bit string of the same length; that bit string, interpreted as a binary number, is usually displayed in code tables in octal, decimal or hexadecimal notation.
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In the original address definition, the most significant eight bits of the 32-bit IPv4 address was the network number field which specified the particular network a host was attached to. The remaining 24 bits specified the local address, also called rest field (the rest of the address), which uniquely identified a host connected to that network. This format was sufficient at a time when only a few large networks existed, such as the ARPANET (network number 10), and before the wide proliferation of local area networks (LANs). As a consequence of this architecture, the address space supported only a low number (254) of independent networks.
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Machine code orders were written in a form of octal officially named syllabic octal (also known as 'slob-octal' or 'slob' notation,). It represented 8 bits with three octal digits but the first digit represented only the two most-significant bits, whilst the others the remaining two groups of three bits each. Although the word 'byte' had been coined by the designers of the IBM 7030 Stretch for a group of eight bits, it was not yet well known, and English Electric used the word 'syllable' for what is now called a byte. Within English Electric, its predecessor, DEUCE, had a well-used matrix scheme based on GIP (General Interpretive Programme).
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Virtual addresses 0 thru 15 are reserved to reference the corresponding general purpose register, and are not mapped. Otherwise, in virtual memory mode the high-order eight bits of an address, called virtual page number, are used as an index to an array of 256 13-bit memory map registers. The thirteen bits from the map register plus the remaining nine bits of the virtual address form the address used to access real memory. Access protection is implemented using a separate array of 256 two-bit access control codes, one per virtual page (512 words), indicating a combination of read/write/execute or no access to that page.
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Syllabic octal is an 8-bit octal number representation that was used by English Electric in conjunction with their KDF9 machine in the mid-1960s. Although the word 'byte' had been coined by the designers of the IBM 7030 Stretch for a group of eight bits, it was not yet well known, and English Electric used the word 'syllable' for what is now called a byte. Machine code programming used an unusual form of octal, known locally as 'bastardized octal'. It represented 8 bits with three octal digits but the first digit represented only the two most-significant bits, whilst the others the remaining two groups of three bits each.
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Multiple bits may be expressed and represented in several ways. For convenience of representing commonly reoccurring groups of bits in information technology, several units of information have traditionally been used. The most common is the unit byte, coined by Werner Buchholz in June 1956, which historically was used to represent the group of bits used to encode a single character of text (until UTF-8 multibyte encoding took over) in a computer and for this reason it was used as the basic addressable element in many computer architectures. The trend in hardware design converged on the most common implementation of using eight bits per byte, as it is widely used today.
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In computing and telecommunications, a unit of information is the capacity of some standard data storage system or communication channel, used to measure the capacities of other systems and channels. In information theory, units of information are also used to measure the entropy of random variables and information contained in messages. The most commonly used units of data storage capacity are the bit, the capacity of a system that has only two states, and the byte (or octet), which is equivalent to eight bits. Multiples of these units can be formed from these with the SI prefixes (power-of-ten prefixes) or the newer IEC binary prefixes (power-of-two prefixes).
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CHS addressing with 28 bits (EIDE and ATA-2) permits eight bits for sectors still starting at 1, i.e., sectors 1...255, four bits for heads 0...15, and sixteen bits for cylinders 0...65535. This results in a roughly 128 GB limit; actually `65536×16×255=267386880` sectors corresponding to 130560 MB for a sector size of 512 bytes. The `28=16+4+8` bits in the ATA-2 specification are also covered by Ralf Brown's Interrupt List, and an old working draft of this now expired standard was published. With an old BIOS limit of 1024 cylinders and the ATA limit of 16 heads the combined effect was `1024×16×63=1032192` sectors, i.e.
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Note that 8b/10b is the encoding scheme, not a specific code. While many applications do use the same code, there exist some incompatible implementations; for example, Transition Minimized Differential Signaling, which also expands 8 bits to 10 bits, but it uses a completely different method to do so. 64b/66b encoding, introduced for 10 Gigabit Ethernet's 10GBASE-R Physical Medium Dependent (PMD) interfaces, is a lower-overhead alternative to 8b/10b encoding, having a two- bit overhead per 64 bits (instead of eight bits) of encoded data. This scheme is considerably different in design from 8b/10b encoding, and does not explicitly guarantee DC balance, short run length, and transition density (these features are achieved statistically via scrambling).
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Most computers internally used eight-bit bytes but communication (seen as inherently unreliable) used seven data bits plus one parity bit. In time, it became common to use all eight bits for data, creating space for another 128 characters. In the early days most of these were system specific, but gradually the ISO/IEC 8859 standards emerged to provide some cross- platform similarity to enable information interchange.. Towards the end of the 20th century, as storage and memory costs fell, the issues associated with multiple meanings of a given eight-bit code (there are seven ISO-Latin code sets alone) have ceased to be justified. All major operating systems have moved to Unicode as their main internal representation.
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In either approach, the byte value is encoded in the low eight bits of the output code point. These encodings are very useful because they avoid the need to deal with "invalid" byte strings until much later, if at all, and allow "text" and "data" byte arrays to be the same object. If a program wants to use UTF-16 internally these are required to preserve and use filenames that can use invalid UTF-8; as the Windows filesystem API uses UTF-16, the need to support invalid UTF-8 is less there. For the encoding to be reversible, the standard UTF-8 encodings of the code points used for erroneous bytes must be considered invalid.
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Historically, a byte was the number of bits used to encode a character of text in the computer, which depended on computer hardware architecture; but today it almost always means eight bits – that is, an octet. A byte can represent 256 (28) distinct values, such as non-negative integers from 0 to 255, or signed integers from −128 to 127. The IEEE 1541-2002 standard specifies "B" (upper case) as the symbol for byte (IEC 80000-13 uses "o" for octet in French, but also allows "B" in English, which is what is actually being used). Bytes, or multiples thereof, are almost always used to specify the sizes of computer files and the capacity of storage units.
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The ARM2 featured a 32-bit data bus, 26-bit address space and 27 32-bit registers. Eight bits from the program counter register were available for other purposes; the top six bits (available because of the 26-bit address space) served as status flags, and the bottom two bits (available because the program counter was always word-aligned) were used for setting modes. The address bus was extended to 32 bits in the ARM6, but program code still had to lie within the first 64 MB of memory in 26-bit compatibility mode, due to the reserved bits for the status flags. The ARM2 had a transistor count of just 30,000, compared to Motorola's six-year-older 68000 model with around 40,000.
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As a consequence, numbers of this form show up frequently in computer software. As an example, a video game running on an 8-bit system might limit the score or the number of items the player can hold to 255—the result of using a byte, which is 8 bits long, to store the number, giving a maximum value of . For example, in the original Legend of Zelda the main character was limited to carrying 255 rupees (the currency of the game) at any given time, and the video game Pac-Man famously has a kill screen at level 256\. Powers of two are often used to measure computer memory. A byte is now considered eight bits (an octet, resulting in the possibility of 256 values (28).
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According to Roberts, the main difference between the games is the PlayStation Vita's use of the effects via the GPU whereas the PlayStation 3 relies on SPUs. The team decided to use anti-aliased colour buffers rather than depth buffers for real- time shadow rendering, giving the game better transparency effects because the memory cost of anti-aliasing is eight bits per pixel so 4x multisample anti- aliasing (MSAA) buffers contain the same amount of memory as a 32-bit depth buffer. Roberts also considered tone mapping to be an improvement, partly because of the Vita's superior support of buffer formats, which gives Wipeout 2048 better exposure control and bloom effects. To accommodate the game's visual fidelity, the team compromised on the frame rate.
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By that time competition from IBM had made the Philco computer operations no longer profitable for Ford, and the division was closed down. Philco 212 at the thumb The Model 212 could carry out a floating-point multiplication in 22 microseconds. Each word contained two 24-bit instructions with 16 bits of address information and eight bits for the opcode. There were 225 different valid opcodes in the Model 212; invalid opcodes were detected and halted the machine. The CPU had an accumulator register of 48 bits, three general-purpose registers of 24 bits, and 32 index registers of 15 bits. Main memory size ranged from 4K words to 64K words. Only the first model had a magnetic drum memory; later editions used tape drives.
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Panasonic AJ-D350 D3 VCR D-3 is an uncompressed composite digital video videocassette format invented at NHK and introduced commercially by Panasonic. It was launched in 1991 to compete with Ampex's D-2. D-3 uses half-inch metal particle tape at 83.88 mm/s (compare to D-2's 19 mm and 131.7 mm/s). Like D-2, the composite video signal is sampled at four times the color subcarrier frequency, with eight bits per sample. Four channels of 48 kHz 16–20 bit PCM audio, and other ancillary data, are inserted during the vertical blanking interval. The aggregate net (error corrected) bitrate of the format is 143 Mbit/s, and because the codec is lossless, it has been used in data applications.
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A device called a head reads and writes data in a hard drive by manipulating the magnetic medium that composes the surface of an associated disk platter. Naturally, a platter has 2 sides and thus 2 surfaces on which data can be manipulated; usually there are 2 heads per platter, one per side. (Sometimes the term side is substituted for head, since platters might be separated from their head assemblies, as with the removable media of a floppy drive.) The `CHS` addressing supported in IBM-PC compatible BIOSes code used eight bits for - theoretically up to 256 heads counted as head 0 up to 255 (`FFh`). However, a bug in all versions of Microsoft DOS/IBM PC DOS up to and including 7.10 will cause these operating systems to crash on boot when encountering volumes with 256 heads.
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Also, giving an angle in degrees, minutes and seconds (with decimals), or a time in days, hours, minutes and seconds, can be interpreted as mixed-radix systems. Sequences where each weight is not an integral multiple of the previous weight may also be used, but then every integer may not have a unique representation. For example, Fibonacci coding uses the digits 0 and 1, weighted according to the Fibonacci sequence (1, 2, 3, 5, 8, ...); a unique representation of all non-negative integers may be ensured by forbidding consecutive 1s. Binary-coded decimal (BCD) are mixed base systems where bits (binary digits) are used to express decimal digits. E.g., in 1001 0011, each group of four bits may represent a decimal digit (in this example 9 and 3, so the eight bits combined represent decimal 93).
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If more error- correcting bits are included with a message, and if those bits can be arranged such that different incorrect bits produce different error results, then bad bits could be identified. In a seven-bit message, there are seven possible single bit errors, so three error control bits could potentially specify not only that an error occurred but also which bit caused the error. Hamming studied the existing coding schemes, including two-of-five, and generalized their concepts. To start with, he developed a nomenclature to describe the system, including the number of data bits and error-correction bits in a block. For instance, parity includes a single bit for any data word, so assuming ASCII words with seven bits, Hamming described this as an (8,7) code, with eight bits in total, of which seven are data.
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The 128-bit (16-byte) MD5 hashes (also termed message digests) are typically represented as a sequence of 32 hexadecimal digits. The following demonstrates a 43-byte ASCII input and the corresponding MD5 hash: MD5("The quick brown fox jumps over the lazy dog") = 9e107d9d372bb6826bd81d3542a419d6 Even a small change in the message will (with overwhelming probability) result in a mostly different hash, due to the avalanche effect. For example, adding a period to the end of the sentence: MD5("The quick brown fox jumps over the lazy dog") = e4d909c290d0fb1ca068ffaddf22cbd0 The hash of the zero-length string is: MD5("") = d41d8cd98f00b204e9800998ecf8427e The MD5 algorithm is specified for messages consisting of any number of bits; it is not limited to multiples of eight bits (octets, bytes). Some MD5 implementations such as md5sum might be limited to octets, or they might not support streaming for messages of an initially undetermined length.
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For purposes of such synchronization, the TCB will usually issue a WAITR, SVC 1, specifying a list of Event Control Blocks (ECBs; one ECB per SRB, plus one for the system operator), and each SRB will indicate its completion to the TCB by using a "branch entry" to the POST system service (which is normally SVC 2, but in this special case would be a call to the address contained in CVT0PT01), and specifying the ECB which is associated with its SRB, and possibly a "message" to the TCB. The "message", should it be present, is often placed in the lowest 24 bits of the ECB, and which is otherwise unused. The highest eight bits are used by the system. Disk device access and network device access is available to SRBs using the "improved control interval processing" feature of VSAM and the "fast path" feature of VTAM, respectively.
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Depending on the clock frequency, the number of memory wait states, as well as on the characteristics of the particular application program, the average performance for the Intel 8088 ranged approximately from 0.33 to 1 million instructions per second. Meanwhile, the `mov reg,reg` and `ALU reg,reg` instructions, taking two and three cycles respectively, yielded an absolute peak performance of between and MIPS per MHz, that is, somewhere in the range 3–5 MIPS at 10 MHz. The speed of the execution unit (EU) and the bus of the 8086 CPU was well balanced; with a typical instruction mix, an 8086 could execute instructions out of the prefetch queue a good bit of the time. Cutting down the bus to eight bits made it a serious bottleneck in the 8088. With the speed of instruction fetch reduced by 50% in the 8088 as compared to the 8086, a sequence of fast instructions can quickly drain the four-byte prefetch queue.
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JIS X 0208 prescribes a set of 6879 graphical characters that correspond to two-byte codes with either seven or eight bits to the byte; in JIS X 0208, this is called the , which includes 6355 kanji as well as 524 , including characters such as Latin letters, kana, and so forth. ;Special characters :Occupies rows 1 and 2. There are 18 such as the "ideographic space" ( ), and the Japanese comma and period; eight diacritical marks such as dakuten and handakuten; 10 characters for such as the Iteration mark; 22 ; 45 ; and 32 unit symbols, which includes the currency sign and the postal mark, for a total of 147 characters. ;Numerals :Occupies part of row 3. The ten digits from "0" to "9". ;Latin letters :Occupies part of row 3. The 26 letters of the English alphabet in uppercase and lowercase form for a total of 52. ;Hiragana :Occupies row 4. Contains 48 unvoiced kana (including the obsolete wi and we), 20 voiced kana (dakuten), 5 semi-voiced kana (handakuten), 10 small kana for palatalized and assimilated sounds, for a total of 83 characters.
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As described above, the S/370 product line underwent a major architectural change: expansion of its address space from 24 to 31 bits. The evolution of S/370 addressing was always complicated by the basic S/360 instruction set design, and its large installed code base, which relied on a 24-bit logical address. (In particular, a heavily used machine instruction, "Load Address" (LA), explicitly cleared the top eight bits of the address being placed in a register. This created enormous migration problems for existing software.) The strategy chosen was to implement expanded addressing in three stages: # first at the physical level (to enable more memory hardware per system) # then at the operating system level (to let system software access multiple address spaces and utilize larger address spaces) # finally at the application level (to let new applications access larger address spaces) Since the core S/360 instruction set remained geared to a 24-bit universe, this third step would require a real break from the status quo; existing assembly language applications would of course not benefit, and new compilers would be needed before non-assembler applications could be migrated.
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The byte is a unit of digital information that most commonly consists of eight bits. Historically, the byte was the number of bits used to encode a single character of text in a computer and for this reason it is the smallest addressable unit of memory in many computer architectures. To disambiguate arbitrarily sized bytes from the common 8-bit definition, network protocol documents such as The Internet Protocol (RFC 791)(1981) refer to an 8-bit byte as an octet. The size of the byte has historically been hardware dependent and no definitive standards existed that mandated the size. Sizes from 1 to 48 bits have been used. The six-bit character code was an often used implementation in early encoding systems and computers using six-bit and nine- bit bytes were common in the 1960s. These systems often had memory words of 12, 18, 24, 30, 36, 48, or 60 bits, corresponding to 2, 3, 4, 5, 6, 8, or 10 six-bit bytes. In this era, bit groupings in the instruction stream were often referred to as syllables or slab, before the term byte became common.
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